IPAC2013 - List of Keywords (controls)

Paper	Title	Other Keywords	Page
MOPEA021	Status of the HESR Electron Cooler Test Set-up	electron, simulation, cathode, vacuum	115
	M.W. Bruker, K. Aulenbacher, J. Dietrich, S. Friederich, A. Hofmann, T. Weilbach HIM, Mainz, Germany K. Aulenbacher IKP, Mainz, Germany
	For the proposed High Energy Storage Ring (HESR) at FAIR, it is foreseen to install an electron cooling device with a beam current of 3 A and a beam energy of 8 MeV. A test set-up was built at Helmholtz-Insitut Mainz (HIM) to conduct a feasibility study. One of the main goals of the test set-up is to evaluate the gun design proposed by TSL (Uppsala) with respect to vacuum handling, EM fields and the resulting beam parameters. Another purpose of the set-up is to achieve an energy recuperation efficiency of 1 - 10^-5. To measure this quantity, a Wien filter has to be employed, which will also prove capable of mitigating collection losses. The current status of the project will be presented.

MOPEA044	Maintenance Experience for Personnel Safety System at SSRF	PLC, radiation, synchrotron, synchrotron-radiation	175
	J.J. Lu, P. Fei, G. Wang, X. Xia, J.Q. Xu, X.J. Xu SINAP, Shanghai, People's Republic of China
	To improve reliability and reduce faults of Personal Safety System (PSS) at Shanghai Synchrotron Radiation Facility (SSRF), two types of system maintenances were carried out since SSRF completion in 2009. The maintenances include maintenance during machine operation and that during shutdown period. The failures of the PSS are summarized for last 3 years operation, and the causes of these failures are analyzed. Main failures were occurred in the access control system and UPS power-supply mode during last 3 years operation. To treat these failures, detail maintenance plan and system upgrading schemes were carried out. After the maintenance and system upgrading, the numbers of beam shutdown which caused directly by the PSS failures are obviously reduced. It was 4 times beam shutdown in 2009 and 0 in 2011.

MOPEA053	Status of NSLS-II Booster	booster, dipole, vacuum, septum	196
	S.M. Gurov, A.I. Erokhin, S.E. Karnaev, V.A. Kiselev, E.B. Levichev, A. Polyansky, A.M. Semenov, S.V. Shiyankov, S.V. Sinyatkin, V.V. Smaluk BINP SB RAS, Novosibirsk, Russia H.-C. Hseuh, T.V. Shaftan BNL, Upton, Long Island, New York, USA
	The National Synchrotron Light Source II is a third generation light source under construction at Brookhaven National Laboratory. The project includes a highly optimized 3 GeV electron storage ring, linac pre-injector and full-energy injector-synchrotron. Budker Institute of Nuclear Physics build booster for NSLS-II. The booster should accelerate the electron beam continuously and reliably from a minimum 170 MeV injection energy to a maximum energy of 3.15 GeV and average beam current of 20 mA. The booster shall be capable of multi-bunch and single bunch operation. Pre-comissioning test results of booster components and system are reviewed.

MOPEA054	A Review of 14 Years of Operation of Helios2 at SSLS	dipole, cryogenics, microtron, gun	199
	Z.W. Li, M. Breese, E.P. Chew, C. Diao, M. Hua, A.W. Wong SSLS, Singapore, Singapore
	In this paper, we present the current status of the superconducting Helios2 Synchrotron and review its major problems and their solutions over the last 14 years. We described how various breakdowns in the cryogenics system, the control system, the RF system, Dipole power supplies, Ring gate valves and helium compressor have all been overcome and what valuable lessons have been learned in operating this machine.

MOPFI031	Progress on the Construction of the 100 MeV / 100 kW Electron Linac for the NSC KIPT Neutron Source	linac, electron, neutron, dipole	351
	Y.L. Chi, J. Cao, P. Chen, B. Deng, C.D. Deng, D.Y. He, X. He, M. Hou, X.C. Kong, Q. Le, X.P. Li, J. Liu, R.L. Liu, W.B. Liu, H.Z. Ma, G. Pei, S. Pei, H. Song, L. Wang, S.H. Wang, X. Wang, Q. Yang, J. Yue, J.B. Zhao, J.X. Zhao, Z.S. Zhou IHEP, Beijing, People's Republic of China M.I. Ayzatskiy, I.M. Karnaukhov, V.A. Kushnir, V.V. Mytrochenko, A.Y. Zelinsky NSC/KIPT, Kharkov, Ukraine Y. Gohar ANL, Argonne, USA
	IHEP, China is constructing a 100 MeV / 100 kW electron linac for NSC KIPT, Ukraine. This linac will be used as the driver of a neutron source based on a subcritical assembly. In 2012, the injector part of the linac was pre-installed as a testing facility in the experimental hall #2 of IHEP. The injector beam and key hardware testing results were satisfying. Recently, the injector testing facility was disassembled and all of the components for the whole linac have been shipped to Ukraine from China by ocean shipping. The installation of the whole machine in KIPT will be started in June. The progress on the construction are reported, injector beam and key hardware testing results are presented.

MOPFI081	Correlating Structure and Function - In situ X-ray Analysis of High QE Alkali-antimonide Photocathodes	cathode, scattering, emittance, vacuum	464
	J. Smedley, K. Attenkofer, S.G. Schubert BNL, Upton, Long Island, New York, USA I. Ben-Zvi, X. Liang, E.M. Muller, M. Ruiz-Osés Stony Brook University, Stony Brook, USA T. Forrest, H.A. Padmore, T. Vecchione, J.J. Wong LBNL, Berkeley, California, USA J. Xie ANL, Argonne, USA
	Funding: The authors wish to acknowledge the support of the US DOE, under Contract No. KC0407-ALSJNT-I0013, DE-AC02-98CH10886 and DE-SC0005713. Use of CHESS is supported by NSF award DMR-0936384. Alkali antimonide photocathodes have high quantum efficiency and low emittance when illuminated by visible light, and are thought to be well suited for use in high-brightness photoinjectors of 4th generation light sources. Here we report on the growth of multi-alkali K2CsSb cathodes on [100] silicon substrates measured using in-situ X-ray diffraction (XRD) and X-ray reflection (XRR). Correlations between cathode structure and growth parameters and the resulting quantum efficiency (QE) are also explored. The best cathodes have a QE at 532 nm in excess of 6% and are structurally textured K2CsSb with grain sizes in excess of 20 nm. In an attempt to reduce the complexity of the current growth methodology we are also making alkali antimonides in parallel via the reaction of bulk materials in an inert environment. This approach has the advantage that the desired stoichiometry can be obtained exactly. Initial diffraction results from prepared bulk materials are promising and show the formation of well reacted K3Sb. In the future we intend to transfer this material to smooth thin photocathode films by either sputtering or pulsed laser deposition.

MOPME024	Status of Beam Loss Spatial Distribution Measurements at J-PARC Linac	proton, linac, status, klystron	524
	H. Sako, T. Maruta, A. Miura JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	Funding: This work was supported by JSPS KAKENHI Grant Number 24510134. We have developed 8-plane (4 horizontal and 4 vertical) scintillating fiber hodoscope system to measure proton tracks due to beam loss in the ACS section at the J-PARC linac. The detector consists of upstream 4 planes (two horizontal and two vertical) and downstream 4 planes (two horizontal and 4 vertical). The time of flight measuremments between the upstream and downstream subsystems allow proton identification and energy mesurements. In summer of 2012, we have installed remote position movement system, which enables measurements of spatial distributions of proton tracks. In this presentation we show status of mesurements and data analysis.

MOPME070	Emittance and Beta Functions Measurements for the MAX IV Linac	quadrupole, emittance, simulation, linac	640
	N. Čutić, E. Mansten MAX-lab, Lund, Sweden
	We plan to determine beam emittance and Twiss parameters for the MAX IV linac using multiple-quadrupoles scans. We investigate the possibility to perform such scans using matching sections' quadrupoles combined with beam profile measurements by fluorescent YAG screens. Beam pipe size, resolution and screen saturation limits and strengths of quadrupoles are taken into consideration. Our approach to this problem using Kalman filter is presented.

MOPWA001	Development of a High Precision Integrator for Analog Signals to Measure Magnetic Fields in Realtime	pick-up, synchrotron, ion, feedback	661
	E. Feldmeier, Th. Haberer HIT, Heidelberg, Germany
	For the Magnetic Field Control of the synchrotron at the Heidelberg Ion Therapy Centre the magnetic fields are measured with a pickup coil along the beam pipe. The induced pickup voltage, corresponding to changes in the magnetic field, has to be integrated in realtime to determine the actual field. A high precision integrator has been developed to measure fields with an accuracy of 4ppm over 10 seconds. This new integrator has a very low drift and calibrates during the measurement. It is the fastest and most accurate integrator for integrating analoge voltages in realtime.

MOPWA002	New Purposed High Precision Power Supply For Quadrupole Magnets Of ILSF using Low Resolution Digital PWM	power-supply, quadrupole, storage-ring, feedback	664
	M. Jafarzadeh, M. Akbari, J. Rahighi, D. Shirangi, E.H. Yousefi ILSF, Tehran, Iran
	A total number of 10⁴ quadrupole magnets, split into 9 families, will be required for the ISLF storage ring lattice. Each quadrupole magnet is connected with its own independent power supply. In new design for quadrupole magnets, the outputs of two synchronized push-pull converters (one for coarse regulation and another for fine current regulation) will be added together before a synchronous rectification. In this manner, there will be no need for extra high-current electronic parts. Another advantage of this design is using a high-voltage inductor on the switching side rather than a high current inductor ion the high current side. The PWM signal to control of buck converter (at the input stage of each unit) will be generated inside a dsPIC .

MOPWA005	Development of a Feedback Control System for Resonant Power Supplies in the J-PARC 3-GeV Synchrotron	power-supply, feedback, impedance, quadrupole	672
	Y. Watanabe JAEA, Ibaraki-ken, Japan N. Tani JAEA/J-PARC, Tokai-mura, Japan
	In the J-PARC 3-GeV Synchrotron, dipole magnets and seven families of quadrupole magnets are excited with a DC-biased 25 Hz sinusoidal waveforms using an individual resonant circuits. This paper proposed a feedback system to improve the amplitude and phase stability, specially against variation of capacitance caused by temperature characteristics in the resonant circuits. The control system has been successfully demonstrated and achieved amplitude and phase stability under ±0.005% and ±0.5 uS, respectively.

MOPWA006	Magnet Power Supply with Small Ripple using Sub-converter and Symmetrical Structure	power-supply, feedback, sextupole, extraction	675
	S. Nakamura J-PARC, KEK & JAEA, Ibaraki-ken, Japan S. Yamada KEK, Tokai, Ibaraki, Japan
	High precision tracking and small current ripple are necessary for a magnet power supply of a high power accelerator. A prototype power supply of the 100kW class is developed with an aim of small current ripple less than 10ppm, which employs a combination of main and sub-converter with symmetrical structure. The main converter unit supplies pattern current by a voltage feedforward control, while the sub-converters by a current feedback control. The symmetrical structure of the power supply is adopted to decouple normal mode and common mode ripples. Each converter unit is modularized and surrounded by a Faraday cage suppress for suppressing radiation of electrical noise and ease for maintenance. Its performance is studied using a set of 24 units of setupole magnets installed in J-PARC Main Ring.

MOPWA008	Power Supply of the Pulse Steering Magnet for Changing the Painting Area between the MLF and the MR at J-PARC 3 GeV RCS	power-supply, injection, superconductivity, proton	681
	T. Takayanagi, N. Hayashi, K. Horino, M. Kinsho, T. Togashi, T. Ueno, Y. Watanabe JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan Y. Irie KEK, Ibaraki, Japan
	The power supply of the pulse steering magnet (PSTR) has been produced. The PSTR of the 3-GeV RCS (Rapid Cycling Synchrotron) in the J-PARC (Japan Proton Accelerator Research Complex) aims at changing the painting area in a pulse-to-pulse mode at 25Hz between the MLF (Material and Life science Experimental Facility) and the MR (50-GeV Main Ring synchrotron) at J-PARC. The power supply has the equipment used to excite the pulse current and the direct current (DC) to correspond to two modes that the paint injection for beam users and the central injection for beam commissioning. In case of the paint injection, the power supply excites the current from 40 A to 450 A in pulse mode, which has the capability to switch from positive to negative polarity. The pulse current has been performed with good accuracy whose deviation to a setting current becomes to be less than ± 0.2 %. In case of the central injection, the power supply excites the current from 1000 A to 3000A in DC mode, which has been realized output current deviation below ± 0.01 %. This paper summarizes the design parameters and the experimental results of the power supply.

MOPWA013	The New Injection System of the HLS II	septum, kicker, pulsed-power, storage-ring	687
	L. Shang, Y. Lu, F. Shang, Y.Y. Wang USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: The program is funded by NSFC with No. 10875116 and No. 11175181 The 0.8GeV storege ring is being rebuilt in NSRL. The design and construction of the new injection system of the new ring is presented. Kicker magnet, septum magnet and their pulsed power suplies are described. Test results are given. The ceramic chambers, vacuum tank of the septum magnet, system timing and local pulsed power control are also described. The installation and testing of the new system undergoing.

MOPWA014	Research and Design of Digital Power Supply for HIRFL-RIBLL Corrector Magnet	power-supply, feedback, secondary-beams, ion	690
	Y.Z. Huang, Y.X. Chen, D.Q. Gao, J.B. Shangguan, R.K. Wang, H.H. Yan, Z.Z. Zhou IMP, Lanzhou, People's Republic of China
	One digital power supply was designed for RIBLL (Radioactive Ion Beam Line in Lanzhou) corrector magnet at HIRFL (Heavy Ion Research Facility in Lanzhou). Adopting two parallel connected IGBT full-bridges as the power circuit topology, the power supply can generate bipolar DC current when it runs in the fourquadrant working states, which well meets the requirements of corrector magnet. SOPC platform of Altera based on Nios II is chosen to design the digital power supply regulator. Employing FPGA as the control core and utilizing SOPC principles, the digital regulator is designed against special requirements of accelerator power supply. The test results indicate that performance of the power supply can meet the design requirements.

MOPWA015	The Control Strategy Research on Two Kinds of Topological Pulse Power Supply	power-supply, pulsed-power, heavy-ion, quadrupole	693
	C.F. Shi, D.Q. Gao, Y.Z. Huang, H.H. Yan, Z.Z. Zhou IMP, Lanzhou, People's Republic of China
	This paper introduces a kind of pulsed power supply at HIRFL-CSR，analyzes the ripple and current error of the quadrupole magnet power supply in the operation process, and gives a two-stage topology of pulsed power supply. The control method is simulinked and the results show that the new one can make up for the deficiencies of the existing pulse power supply and the main circuit structure and control method are feasible.

MOPWA019	Digital Power Supply Controller Development Based on FPGA	power-supply, booster, synchrotron, synchrotron-radiation	702
	R.N. Xu, C.L. Guo, D.M. Li, R. Li, S. Tan, W.F. Wu SINAP, Shanghai, People's Republic of China
	A digital power supply controller of SSRF (Shanghai Synchrotron Radiation Facility) adops advanced DSP, FPGA and precision ADC as core unit and data acquisition unit. The controller, which is embedded in the power supply case, is composed of two cards, DSP card and ADC card. The controller can communicate with IOC by optical fiber via the Ethernet, Manchester or RS-232 port. The parameters of adjusting power supply can be easily changed to achieve high stability and repeatability. The long-term stability is better than 20ppm. The resolution of current is better than 5ppm. As a replacement of imported PSI controller, the controller is mainly used in middle power supplies in SSRF, and it could accord with all the technical requirements of the facility.

MOPWA023	A Low Jitter Pulse Generator Based on Two-stage Storage Module	pulsed-power, coupling, simulation, high-voltage	711
	J.N. Li, W.Q. Chen, F. Guo, W. Jia NINT, Xi'an, People's Republic of China
	A scheme for a low jitter pulse generator based on two-stage storage module is described. The thyristor is used for the first stage of the generator, the UV-illumination gas switch is used for the second stage of the generator. Between them, the pulsed transformer is used for connecting. A capacitance-resistance coupling structure was designed to produce UV light which triggered the switch to decrease the breakdown jitter. The test result shows, the risetime of the current is 0.73μs, the peak value of the current is 1.8kA on 1.1Ω load. The delay of the generator is 35.1μs, and the jitter of the generator attaches to 0.22μs.

MOPWA025	2Hz Ramping Mode Dipole Power Supply for Testing the NSLSII Booster Dipole Magnets	power-supply, dipole, booster, feedback	714
	A.I. Erokhin, A.V. Bulatov, K. Gorchakov, S.M. Gurov, V.V. Kolmogorov, A.A. Kremnev, D.N. Pureskin, D.V. Senkov, R.V. Vakhrushev BINP SB RAS, Novosibirsk, Russia
	Budker Institute has designed and delivered Booster for NSLSII project including vacuum system, magnet system, diagnostics and power supplies. Dipole power supplies were directly delivered to BNL by sub-contractor (Danfysik, Denmark). To test dipole magnets on factory side, at BINP, it was decided to design and construct a high current ramping mode power supply. The designed power supply can operate with the reactive output power up to 150kVA and output current up to 900A at 2Hz ramping mode. The absolute accuracy achieved is better than 100ppm for the injection and extraction flats and better than 500ppm for the ramps.

MOPWA028	Power System for Quadrupole Magnets of NSLS-II 3 GeV Booster	quadrupole, booster, extraction, injection	723
	D.V. Senkov, A.I. Erokhin, V.V. Kolmogorov, A.S. Medvedko, S.I. Potapov, D.N. Pureskin BINP SB RAS, Novosibirsk, Russia
	Power system for quadrupole magnets of NSLS-II 3 GeV booster is designed, manufactured and tested in BINP, Russia. The power system consists of 2 parts. The first part is a charging source with a capacitance bank at output. And the second part consists of 3 current sources powered by a capacitance bank. The charging source output voltage is up to 180 V, peak power is 40 kW and average power is 20 kW. Capacitance bank has a 120 kVA storage energy. The second part contains 3 independent current sources with up to 180 A output current each. This report considers the details of current sources design, their parameters and results of inspection test in BINP. Finally, the first results of injection and extraction section commissioning at BNL site are reported.

MOPWA029	Pulse Generators for Septums and Bumps of Injection and Extraction Systems of NSLS-II Booster	septum, injection, extraction, booster	726
	D.V. Senkov, A.M. Batrakov, A.D. Chernyakin, V.A. Kiselev, A.V. Pavlenko, A.N. Zhuravlev BINP SB RAS, Novosibirsk, Russia
	Pulse generators for injection and extraction systems of NSLS-II 3 GeV booster are designed, manufactured and tested in BINP, Russia and installed and tested at BNL site. This report considers the details of bump, injection septum and extraction septum pulse generators design, their parameters and results of inspection test in BINP. The design and electronics features of control system of pulse generators are presented. Finally, the first results of injection and extraction section commissioning at BNL site are reported.

MOPWA040	Bipolar 10A and 50A Magnet Power Supplies for SwissFEL	power-supply, beam-losses, monitoring	756
	R. Künzi, M. Emmenegger PSI, Villigen PSI, Switzerland
	15 years ago the Power Electronics Group at PSI, Switzerland developed power supplies (PS) for the magnets of the Swiss Light Source (SLS). These PS are based on switched mode converters with fully digital control. During the 12 years of operation of the SLS they have shown a very good reliability but also revealed some potential for improvement: After several years of operation the many fans installed started to fail more frequently and the same was observed for “off-the-shelf” AC/DC converters for the DC link. For the new SwissFEL, which shall be in service by 2016, approx. 610 PS rated at 10A and 40 PS rated at 50A will be necessary. As for any accelerator application high stability and reliability of the magnet PS are essential for high beam quality and availability. The development of the SwissFEL PS aims to raise the already good reliability by omitting as many fans as possible and adding redundancy for the AC/DC converters. Presently, a prototype rack with 21 10A PS is available and the mass production has started. The presented paper describes the PS concept and test results of the prototype regarding stability and efficiency are given.

MOPWA046	The Multi-channel Measuring Data Acquisition Interface for TPS Quadrupole and Sextupole Magnet Power Supplies by using LabVIEW as the Developing Tool	power-supply, quadrupole, sextupole, LabView	774
	B.S. Wang, Y.-C. Chien, C.-Y. Liu, K.-B. Liu NSRRC, Hsinchu, Taiwan H.P. Tsai Chroma ATE Inc., Taiwan
	This paper presents an implementation of a multi-channel measuring data acquisition interface of quadrupole and sextupole magnet power supplies (MPS) for Taiwan Photon source (TPS) withLabVIEW as the developing tool. The multi-channel measuring data acquisition interface could reduce quantity of measurement instrument and loading of operator at the MPS acceptance test. The instrument devices of measurement system include a multiplexer 、 a dynamic signal analyzer (DSA) and a multi-channel digital voltage meter (DVM), GPIB is the communication protocol betweenthe multi-channel measuring data acquisition interfaceand instruments. There are threeanalyzing procedure for the output currentof MPSin the default setting of the LabVIEW program, 1) Fast Fourier Transform of output current measured by DSA, 2) long-term stability of output current measured by DVM, 3) the linear error function fitting of output current by LabVEW toolbox;after these three analyzing procedureis completed, the performance of each MPS can be automatically generatedas a Microsoft Word report file.

MOPWA047	Development of a Digital Control Interface Card with a LabVIEW Control Program for TLS Corrector Magnet Power Supply	LabView, feedback, power-supply, monitoring	777
	B.S. Wang, K.-B. Liu NSRRC, Hsinchu, Taiwan
	This paper presents an implementation of a virtual instrument control interface and a digitally controlled interface card for Taiwan Light Source (TLS) corrector magnet power supplies (MPS). Eight pieces of corrector MPS converter module are monitored and controlled by the digitally controlled interface card with delimit boundary of ±10 voltage. The digitally controlled interface card was implemented with an ADS1278 24-bits multi-channel analog-to-digital converter、a DAC8718 16-bits multi-channel digital-to-analog converter and the TMS320F28335 digital signal processor. There are two control modes of the virtual instrument control interface, which are 1) local control mode by RS-232, 2) the remote control by MiiNePort\_E1 TCP/IP protocol; with the developed Labview control interface the user can choose which mode to communicate with the corrector magnet power supplies depending on the working environment.

MOPWA057	Development of a High-resolution, Broad-band, Stripline Beam Position Monitoring System	feedback, monitoring, linear-collider, extraction	804
	G.B. Christian, D.R. Bett, N. Blaskovic Kraljevic, P. Burrows, M.R. Davis, Y.I. Kim, C. Perry JAI, Oxford, United Kingdom R. Apsimon, B. Constance CERN, Geneva, Switzerland P. Burrows, C. Perry Oxford University, Physics Department, Oxford, Oxon, United Kingdom J. Resta IFIC, Valencia, Spain
	A low-latency, sub-micron resolution stripline beam position monitoring system has been developed and tested with beam at the KEK Accelerator Test Facility, where it has been used as part of a feedback system for beam stabilisation. The fast analogue front-end signal processor is based on a single-stage down-mixer and is combined with an FPGA-based system for digitisation and feedback control. A resolution as low as 400 nm has been demonstrated for beam intensities of ~1 nC, with single-pass beam. The latest results of recent modifications to balance the input path lengths to the processor will be discussed. These modifications compensate for the inherent phase sensitivity of the processors, and hence improve the intrinsic resolution, without the need for offline correction. Modifications to the FPGA firmware will also be described, to allow for flexible operation with variable system-synchronous data acquisition at up to 400 MHz, with up to nine data channels of 13-bit width, and a nominal record length of 1 KS/channel/pulse (extensible to a total record length of 120 KS per pulse, for example, for use with long bunch trains or wide-band multi-turn measurements in storage rings).

MOPWA061	A New Tool for Longitudinal Tomography in Fermilab's Main Injector and Recycler Rings	booster, injection, emittance, space-charge	816
	N.J. Evans, S.E. Kopp The University of Texas at Austin, Austin, Texas, USA P. Adamson, D.J. Scott Fermilab, Batavia, USA
	Funding: U.S Department of Energy We are developing software to compute tomographic reconstructions of longitudinal phase space distributions in the Fermi National Accelerator Laboratory Main Injector and Recycler rings using data from existing resistive wall current monitors to diagnose beam quality at injection and provide input distributions for simulation of losses. Building on the algorithm developed by S. Hancock et al. at CERN the software is able to process a full synchrotron period of a Booster batch of 81 bunches with 18.94 ns spacing and a sampling rate of 2.5 GHz, in < 30 sec, or every ~270 injections. Processing an entire injection opens up the possibility of investigating coupled bunch instabilities via tomography. To speed reconstruction for use on a full injection, phase space maps are created once for a given set of parameters and saved for injections with similar machine settings. We present an overview of the system and studies done on the effect of small errors present including: random noise, mismatch between sampling rate and machine period, errors in locating bunch centers, and trigger jitter. Tomographic Measurements of Longitudinal Phase Space Density; 1998 ed. - Hancock, S et al - CERN-PS-98-030-RF

MOPWA065	Affordable, Short Pulse MARX Modulator	high-voltage, shielding, linear-collider, collider	828
	R.A. Phillips, M.P.J. Gaudreau, M.K. Kempkes, B.E. Simpson Diversified Technologies, Inc., Bedford, Massachusetts, USA J.A. Casey Rockfield Research Inc., Las Vegas, Nevada, USA
	Under a U.S. Department of Energy grant, Diversified Technologies, Inc. (DTI) is developing a short pulse, solid-state Marx modulator for the next generation of klystrons and accelerators. For short-pulse modulators, this Marx topology provides a means to achieve astounding risetimes and flattop control that are simply not available with hard switch or transformer coupled topologies. The design is a high peak-power pulse modulator of greater efficiency than presently available, in the 100 kV to 1 MV range, for currents of 0.1 to 1 kA, pulse lengths of 0.2 to 5.0 us, and rise/fall times 10% of pulse length. A key objective of the development effort is a design which is modular and scalable, yet low cost, and easy to manufacture and maintain. The modulator will be delivered to Yale Beam Physics Laboratory for evaluation, and will be affordable for deployment at other national labs for klystron and modulator evaluation. In this paper, DTI will describe the new design and provide an update on progress.

MOPWA066	Components of Heating and Fueling of Fusion Plasmas	high-voltage, simulation, cathode, synchrotron	831
	K. Schrock, M.P.J. Gaudreau, M.K. Kempkes Diversified Technologies, Inc., Bedford, Massachusetts, USA
	Funding: Funded by US DOE, Grant # DE-SC0004250 Next generation fusion facilities will require many megawatts of RF power from dozens of gyrotrons. Each gyrotron requires a power system that must deliver the high-voltage power, modulate cathode voltage, and protect these expensive gyrotrons from arcing damage. It must be highly efficient, to minimize both the power and cooling costs associated with operation and to ensure high facility availability. Diversified Technologies, Inc. (DTI) has bench-tested a table-top scale ‘Buck Matrix’ modulator which uses a single set of IGBT switches for voltage regulation, arc protection, and pulse modulation. Although pulse step modulators represent a one-step solution, their size, and the complexity of their driving transformer make them more expensive than DTI’s two-step approach. DTI’s Buck Matrix modulator, with an efficiency of ~96%, cuts the size of the system in half, using a single layer of solid state switches for both voltage regulation and arc protection/modulation. This cuts the total hardware costs by a~30% or more, and eliminates the need for a separate opening switch or crowbar. DTI will present the system components of the design as well as the performance results to date.

MOPWA067	Robust High-average-power Modulator	klystron, neutron, power-supply, pick-up	834
	I. Roth, N. Butler, M.P.J. Gaudreau, M.K. Kempkes Diversified Technologies, Inc., Bedford, Massachusetts, USA
	Funding: US DOE. Grant No. DE-SC0004254 Diversified Technologies Inc. (DTI) designed a modulator which meets the requirements of the Spallation Neutron Source (SNS) modulators at Oak Ridge National Laboratory and will be less expensive than copies of the current modulators. The SNS modulators, under development for a decade, still do not meet the specifications for voltage, droop, or pulsewidth. The modulators must provide pulses of 85 kV, 165 A, with pulsewidths of 1.5 ms and voltage flatness of 1%. The current modulator switches the full power at high frequency during each pulse, and has a complex output transformer. DTI designed a modulator that meets all specifications and is less expensive. The proposed design is cheaper because there is an HV switch that operates at full current only once per pulse, a corrector that switches only 5% of the power at high frequency, a low-cost transformer-rectifier power supply, and no output transformer. DTI’s patented switch uses IGBTs, allowing the switch to operate at full capacity even if 20% of the devices fail. The modulator will be installed in 2013 at SNS to test klystrons. DTI will present the system components of the design as well as the performance results to date.

MOPWA069	Time-resolved Electron Beam Position Monitor Macropulse Waveform Measurement in MkV Linear Accelerator at University of Hawaii Free Electron Laser Laboratory	electron, FEL, free-electron-laser, laser	837
	P. Niknejadi, M.R. Hadmack, B.T. Jacobson, J. Madey, G.S. Varner University of Hawaii, Honolulu, HI, USA
	Real time waveform measurements of electron beams will provide valuable data and possibility of online bunch diagnostics in linear accelerators. The University of Hawaii Linear Accelerator utilizes a thermionic LaB6 cathode microwave gun injector and a single section of S-band linear accelerator capable of producing a 40MeV, 1-2 ps bunched electron beam with average current of 200mA over the duration of a 4.5 us macropulse. This beam, pulsed at 4 Hz, produces strong RF signal at 2.856 GHz which is coupled out of the beam-pipe by a family of stripline beam position monitors (BPM's) and read out using custom built logarithmic-difference based electronics installed in 2012.* A high speed Analog to Digital Convertor and Field-Programmable Gate Array will be used to digitize the signal and record the waveform. The goal is to make a cost effective oscilloscope on a chip/board with feasible and functional operation to achieve optimal beam configuration. The circuit board design, in-circuit programming, waveform digitization challenges, and preliminary results from the prototype will be presented at the conference. * B. T. Jacobson, M. R. Hadmack, J. M. J. Madey, P. Niknejadi "Modular Logarithmic Amplifier Beam Position Monitor Readout System at University of Hawai’i," IBIC Conf. Proc. (2012)

MOPWA074	High Voltage Converter Modulator Optimization	high-voltage, neutron, feedback, background	852
	A. Scheinker LANL, Los Alamos, New Mexico, USA M.J. Bland University of Nottingham, Nottingham, United Kingdom
	High voltage converter modulators (HVCM) are at the forefront of long pulse high voltage (100kV) technology for Klystron voltage sources. We present results of digitally implementing an extremum seeking (ES) algorithm with which we optimized the rise time of the output voltage of a HVCM at the Los Alamos Neutron Science Center (LANSCE) HVCM test stand by iteratively, simultaneously tuning the first 8 switching edges of each of the three phase drive waveforms (24 variables total). We achieved a 50us rise time, which is reduction in half compared to the 100us currently achieved at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. The ES algorithm is successful despite the noisy measurements and cost calculations, confirming the theoretical predictions that the algorithm is not affected by noise unless it both matches exactly the frequency components of the controller's specific perturbing frequencies and is of comparable size.

MOPWA076	Improvements to Existing Jefferson Lab Wire Scanners	emittance, optics, diagnostics, linac	855
	M.D. McCaughan, M.G. Tiefenback, D.L. Turner JLAB, Newport News, Virginia, USA
	This poster will detail the augmentation of selected existing CEBAF wire scanners with commercially available hardware, PMTs, and self created software in order to improve the scanners both in function and utility. Notice: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.

MOPWA077	EPICS, MATLAB, GigE CCD Camera Based Beam Imaging System for the IAC-RadiaBeam THz Project	EPICS, GUI, optics, background	858
	C.F. Eckman, A. Andrews, T. Downer, Y. Kim, C. O'Neill IAC, Pocatello, IDAHO, USA P. Buaphad, Y. Kim ISU, Pocatello, Idaho, USA Y. Kim JLAB, Newport News, Virginia, USA
	At the Idaho Accelerator Center (IAC) of Idaho State University, we have been operating an L-band RF linear accelerator running at low energies (5 - 44 MeV) for the IAC-RadiaBeam THz project. We have designed and implemented an image acquisition and analysis system that can be used for real time observation of the electron beam, tuning of THz radiation production, and measurement of the transverse beam emittance. The imaging system contains an Yttrium Aluminium Garnet (YAG) screen on an actuator, a Prosilica GC1290 GigE CCD camera with an adjustable lens, a screen illuminator, an optical alignment structure, and a lead tube for the camera shielding. The real time continuous beam images can be acquired by SampleViewer, while the single shot beam image can be acquired by the Experiential Physics and Industrial Control System (EPICS) and areaDetector. In this paper, we describe components of the imaging system, the real time beam image acquisition with SampleViewer, the single shot beam image acquisition with areaDetector, and a remote controllable beam image acquisition via MATLAB Channel Access (MCA), MATLAB, and EPICS.

MOPWA087	Predictive Diagnostics for High-availability Accelerators	diagnostics, monitoring, klystron, extraction	873
	K. Žagar, D. Bokal, K. Strniša Cosylab, Ljubljana, Slovenia M. Gašperin University of West Bohemia, Pilsen, Czech Republic L. Medeiros Romão, D. Vandeplassche SCK•CEN, Mol, Belgium G. Pajor COBIK, Solkan, Slovenia
	In Accelerator Driven Systems, high availability of the accelerator is one of its key requirements. Fortunately, not every beam trip is necessarily a failure. For example, in the proposed MYRRHA transmuter, absence of the beam for less than 3 seconds is still deemed acceptable. Predictive diagnostics strives to predict where a failure is likely to occur, so that a mitigating action can be taken in a more controlled manner, thus preventing failure of other components while exactly pinpointing the component that is about to fail. One approach to predictive diagnostics is to analyze process variables that quantify inputs and outputs of components as archived by the accelerator's distributed control system. By observing trends in their values an impending fault can be predicted. In addition, sensors measuring e.g., vibration, temperature or noise can be attached to critical components. By analyzing the signatures of signals acquired by these sensors, non-nominal behavior can be detected which possibly indicates a looming failure.

MOPWA088	FPGA Development Approach for Accelerator Systems with High Integration Complexity	neutron, alignment	876
	J. Dedič, K. Žagar COBIK, Solkan, Slovenia A.M.M. Aulin Söderqvist, N.H. Claesson, R. Tavčar Cosylab, Ljubljana, Slovenia J. Neves Rodrigues Lund University, Lund, Sweden
	During the application-layer FPGA development for timing system for a medical accelerator (accelerator: MedAustron, timing system: Micro Research Finland) and a couple of other FPGA projects (power supply waveform generator, Machine Protection System proof of concept, ESS timing system demo) we got very good insight on how to approach demanding FPGA development that requires team work of many developers, coupled with particularities of accelerator system development. Because subsystems’ specific requirements evolve together with the operational understanding of the entire machine, the careful balance has to be taken between requirements gathering, prototyping and development stage. Furthermore, when doing architectural design decisions, knowledge from multiple domains should be taken into account; accelerator operation, software development and FPGA development. The design shouldn’t be register or counter centric, and FPGA functionality shouldn’t appear to the software developer as fixed – otherwise the design decisions of one world will sooner or later lead to spaghetti-code workarounds in the other world.

MOPWO018	Cellular Automaton Simulating the Motion of the Charged Particles Beam	acceleration, simulation, lattice	918
	S.N. Andrianov, N.V. Kulabukhova St. Petersburg State University, St. Petersburg, Russia V. Ryabusha Saint Petersburg State University, Saint Petersburg, Russia
	In this research we formulate and formalize the rules for the cellular automaton that emulates the motion of the charged particles beam under the effect of Coulomb force for one-, two- and three-dimensional cases. In this research we also describe the main principles of the realization of this approach in a paralleled cluster environment.

MOPWO019	An IDE for Spin-orbit Dynamics Simulation	simulation, lattice, betatron, optics	921
	A.N. Ivanov, N.V. Kulabukhova St. Petersburg State University, St. Petersburg, Russia
	In this paper a prototype of an IDE for simulation of spin-orbit motion is described. It is based on the component software development and provides a flexible graphic user interface. One of the main parts of it is numerical methods for ordinary differential equations integration. For numerical simulation it is possible use either the matrix map algorithm or traditional step-by-step methods. This workflow allows choosing one of numerical algorithms and to provide necessary computational experiments. It is also contains both a visual designer of an accelerator lattice and additional tools for control parameters of the model. There is also exists possibility for code generation in different programming languages and computation on high-performance systems.

MOPWO020	Space Charge Dominated Envelope Dynamics using GPUs	space-charge, simulation, luminosity, focusing	924
	N.V. Kulabukhova St. Petersburg State University, St. Petersburg, Russia
	High power accelerator facilities lead to necessity to consider space charge forces. It is therefore important to study the space charge dynamics in the corresponding channels. To represent the space charge forces of the beam we have developed special software based on some analytical models for space charge distributions. Because calculations for space charge dynamics become extremely time consuming, we use a special algorithm for predictor-corrector method for evaluation scheme for beam map evaluation including the space charge forces. This method allows us to evaluate the map along the references trajectory and to create the beam envelope dynamics. The corresponding computer codes are realized using CUDA implementation of maps for particle dynamics. Some numerical results for different types of the beam channels are discussed. The survey of advantages and disadvantages of using different methods of parallelization and some parallel approaches will be done.

MOPWO032	SPS Scraping and LHC Transverse Tails	injection, emittance, beam-losses, luminosity	957
	L.N. Drøsdal, K. Cornelis, B. Goddard, V. Kain, M. Meddahi, O. Mete, B. Salvachua, G. Valentino, E. Veyrunes CERN, Geneva, Switzerland
	All high-intensity LHC beams have to be scraped before extraction from the SPS to remove the non-Gaussian transverse tails of the particle distributions. The tail particles would otherwise cause unacceptably high losses during injection or other phases of the LHC cycle. Studies have been carried out to quantify the scraping using injection losses and emittance measurements from wire scanners as diagnostics. Beams scraped in the SPS were scraped again in the LHC with collimators to investigate possible tail repopulation. The results of these studies will be presented in this paper.

MOPWO040	Analysis of Failures of the LHC Collimators during the 2010-2013 Operation	collimation, injection, luminosity, insertion	981
	S. Redaelli, A. Masi CERN, Geneva, Switzerland
	The LHC collimation system must be available in all phases of the machine operation in order to handle the high stored beam energies. The system availability is therefore crucial to achieve an efficient LHC operation. The collimation system has proved to work reliably in the first years of LHC operation, with total stored energies up to 140 MJ. The impact on the machine availability has been limited. The analysis of collimation system availability and the failure rate in the years 2012-2012 is reviewed with the aim to identify possible further improvements for the future.

MOPWO062	A Parallel Multi-objective Differential Evolution Algorithm for Photoinjector Beam Dynamics Optimization	emittance, electron, solenoid, gun	1031
	J. Qiang, C.E. Mitchell, S. Paret, R.D. Ryne LBNL, Berkeley, California, USA Y.X. Chao UCB, Berkeley, California, USA
	Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231 In photoinjector design, there is growing interest in using multi-objective beam dynamics optimization to minimize the final transverse emittances and to maximize the final peak current of the beam. Most previous studies in this area were based on genetic algorithms. Recent progress in optimization suggests that the differential evolution algorithm could perform better in comparison to the genetic algorithm. In this paper, we propose a new parallel multi-objective optimizer based on the differential evolution algorithm for photoinjector beam dynamics optimization. We will discuss the numerical algorithm and some benchmark examples. This algorithm has the potential to significantly reduce the computation time required to reach the optimal Pareto solution.

MOPWO067	Beam Dynamics Simulations with a GPU-accelerated Version of Elegant	simulation, acceleration, collective-effects, storage-ring	1040
	I.V. Pogorelov, K.M. Amyx, J. Balasalle, J.R. King Tech-X, Boulder, Colorado, USA M. Borland, R. Soliday ANL, Argonne, USA
	Funding: Work supported by the US DOE Office of Science, Office of Basic Energy Sciences under grant number DE-SC0004585, and by Tech-X Corporation Large scale particle tracking and tracking-based lattice optimization simulations can derive significant benefit from efficient implementation of general-purpose particle tracking on GPUs. We present the latest results of our work on accelerating Argonne National Lab's accelerator simulation code ELEGANT,* using CUDA-enabled GPUs. A sufficiently large number of Elegant beamline elements has been ported to GPUs to allow the GPU-accelerated simulation of realistic test lattices. We will identify some of performance-limiting factors, and briefly discuss optimization techniques for efficient utilization of the device memory space, with an emphasis on register usage. We also present a novel hardware-assisted technique for efficiently calculating a histogram from a large distribution of particle coordinates, and compare this to data-parallel implementations. * M. Borland, Elegant: A Flexible SDDS-compliant Code for Accelerator Simulation, APS LS-287, September 2000 ** Y. Wang, M. Borland, in Proc. of PAC07, THPAN095 (2007)

MOPWO086	Open XAL Status Report 2013	status, neutron, EPICS, target	1076
	T.A. Pelaia ORNL, Oak Ridge, Tennessee, USA
	Funding: ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725 XAL is the well established, accelerator physics high level application programming framework developed for and used at the Spallation Neutron Source in Oak Ridge National Lab. Due to interest from other accelerator labs, the Open XAL project was formed in 2010 to port XAL to be more suitable for collaboration. The Open XAL architecture along with the objectives, status and roadmap of this effort are presented in this paper.

TUOCB202	Fast Orbit Feedback Scheme and Implementation for Taiwan Photon Source	feedback, power-supply, simulation, EPICS	1146
	P.C. Chiu, K.T. Hsu, K.H. Hu, C.H. Kuo, C.Y. Wu NSRRC, Hsinchu, Taiwan
	TPS (Taiwan Photon Source) is a 3 GeV synchrotron light source which is being in construction at NSRRC. As most of 3rd generation light sources, the fast orbit feedback system would be adopted to eliminate various disturbances and improve orbit stability. Due to the vacuum chamber material made of aluminum with higher conductivity and lower bandwidth, both of slow and fast correctors will be used for FOFB correction. In general, there are two schemes to operate these hybrid correctors. One is to transfer correction from fast to slow correctors periodically and avoid fast corrector saturation. The other is the fast correctors operated only at higher frequency domain and slow ones take care of DC part. TPS would adopt the first scheme but the second one still as a substitute. Both schemes will be supported. This report summarizes the infrastructure of the FOFB and the simulation is also presented.
	Slides TUOCB202 [3.035 MB]

TUODB201	Recent Progress on the Development of a High Gradient RF System using High Impedance Magnetic Alloy, FT3L	cavity, impedance, acceleration, synchrotron	1152
	C. Ohmori, K. Hara, K. Hasegawa, M. Toda, M. Yoshii KEK, Ibaraki, Japan M. Nomura, A. Schnase, T. Shimada, F. Tamura, M. Yamamoto JAEA/J-PARC, Tokai-mura, Japan
	An upgrade project of J-PARC MR (Main Ring) includes developments of high gradient RF cavities and magnet power supplies for high repetition rate. A dedicated production system for high impedance magnetic alloy (FT3L) cores was assembled in J-PARC. This setup demonstrated that we can produce material with two times higher muQf product compared to the cores used for present cavities. And, the new results also show up to 20% higher impedance than the 2011 production with the former setup. In this summer, the system will be used for mass production of 200 FT3L cores for J-PARC MR. The cores produced in 2011 are already used for standard machine operation. The operation experience shows that the power loss in the cores was reduced significantly as expected. The scenario describing the upgrade plan of MR and the cavity replacements is reported. By the replacement plan, the total acceleration voltage will be almost doubled, while the number of RF stations remains the same.
	Slides TUODB201 [5.105 MB]

TUPEA006	Towards Realistic Modelling of the FEL Radiation for the European XFEL	simulation, radiation, FEL, undulator	1173
	I.V. Agapov, G. Geloni XFEL. EU, Hamburg, Germany
	For the operation phase of the European XFEL the possibility to characterize the FEL radiation taking realistic machine model into account is important. To achieve this, a software framework is being developed. It allows for interoperability of various simulation codes by means of a common graphical user interfaces, common input and output files, and common programming model for scripting; it includes the possibility of modeling beam jitters and machine imperfections to set errorbars on the simulation results, and has a connection to the control system for data acquisition. We report on the progress in the developing of this framework and give examples of FEL property calculations performed with it.

TUPEA038	Pre-chirp Control Broadband Non-collinear Optical Parametric Amplifier for the Future Laser Weak-field Accelerator	electron, laser	1223
	L. Shen, C. Feng, L. Feng, D. Wang, H.F. Yao, W.Y. Zhang, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	Ultra-short pulse has been proved to be a very useful tool for accelerating electron close to GeV now. But limited by gain narrowing effect, conventional CPA technology is quite hard to get less than 30fs at high energy level. Non-collinear optical parametric amplification (NOPA) looks more and more attractive for generating super-broadbandwidth pulses which is possible to be compressed to ultra-short pulses. Previous NOPAs, pumped by 400nm pulses, were using BBO crystals to reach shorter signal pulse durations. But the associated spectral bandwidths are still strongly linked with higher order nonlinear effects. which make it quite difficult to get higher energy with short pulse duration. Here we proposed to use pre-chirped few nm bandwidths around 515nm pumped pulses to amplify ultra-short pulses centered at 800nm. In our setup, we have found just one dramatical geometry configuration which support that we have possibility to get amplification from 720nm to 900nm, which will support to less than 10fs by well re-compression. This design is well adapted for BBO crystals. But the idea could be used also for other crystals.

TUPEA044	The Design of Control System for the Optical Cavity Adjuster of a FEL-THz Source	cavity, FEL, electron, undulator	1232
	X. Liu, Q. Fu, B. Qin, P. Tan, C. Wang, Y.Q. Xiong, J. Yang, H. Zeng HUST, Wuhan, People's Republic of China
	The optical cavity adjuster is an important sub-system in a FEL-THz source, which is used to adjust the position and angle of the optical cavity with a high precision. In view of the requirements of the optical cavity adjuster of the FEL-THz source, this paper presents the design of the control system of the optical cavity adjuster. The design of the control system based on a PC and a motion controller is adopted. The motion controller controls high-precision linear stage to adjust linear direction and picomotors are controlled to enable the adjustment of roll and yaw. According to relevant calculation, the range of linear direction and the accuracy can be reached at ±3mm and 0.2~0.5μm; the range of the adjustment of roll and yaw and the accuracy can be reached at ±2° and 20″. In summing up it can be stated that the design meets the requirements and it also lays the foundation for engineering on developing the optical cavity adjuster.

TUPFI010	The LHCb Online Luminosity Control and Monitoring	luminosity, target, dipole, proton	1346
	R. Alemany-Fernandez, F. Follin, R. Jacobsson CERN, Geneva, Switzerland
	The online luminosity control consists of an automatic slow real-time feedback system controlled by specific LHCb software, which communicates directly with a LHC software application. The LHC application drives a set of corrector magnets to adjust the transversal beam overlap at the LHCb interaction point in order to keep the instantaneous luminosity aligned to the target luminosity provided by the experiment. It was proposed and tested first in July 2010, and it has been in routine operation during the first two years of physics luminosity data taking, 2011 and 2012. This paper describes the operational performance of the LHCb experiment and the LHC accelerator during the luminosity control of the experiment, the accounting of the recorded luminosity and dead time of the detector, and analyses the beam stability during the adjustment of the transverse beam overlap at the interaction point.

TUPFI011	Study and Operational Implementation of a Tilted Crossing Angle in LHCb	dipole, luminosity, beam-losses, monitoring	1349
	R. Alemany-Fernandez, F. Follin, B.J. Holzer, D. Jacquet, R. Versteegen, J. Wenninger CERN, Geneva, Switzerland
	The current crossing angle scheme at LHCb interaction point (horizontal crossing angle and vertical beam separation) prohibits the use of the LHCb dipole positive polarity for 25 ns bunch spacing operation since the beam separation at the first parasitic encounter is very small inducing unwanted beam encounters. To overcome this limitation a different crossing angle scheme was proposed in 2007 by W. Herr and Y. Papaphilippou. The new schema implies a vertical external crossing angle that together with the horizontal internal crossing angle, from the LHCb dipole and its three compensator magnets, defines a new tilted crossing and separation plane providing enough beam separation at the parasitic encounters. This paper summarizes the feasibility study of the new crossing scheme, the implementation in routine operation and analyzes the beam stability during the building up of the tilted crossing plane.

TUPFI013	LHC Long Shutdown: A Parenthesis for a Challenge	cryogenics, radiation, vacuum, superconducting-magnet	1355
	K. Foraz, M. Arnaud, M.B.M. Barberan Marin, C. Bedel, M. Bernardini, J. Coupard, J. Etheridge, H. Gaillard, S. Grillot, E. Paulat, A.-L. Perrot CERN, Geneva, Switzerland
	After three fruitful years of operation, the LHC will enter a long shutdown. Major works will be implemented to allow running safely at 7TeV/beam. The LHC superconducting circuits will be consolidated; mitigation measures will be carried out to reduce the single event effects occurrence in the frame of the Radiation To Electronics mitigation project (R2E); all the equipment will be fully maintained. In parallel, numerous consolidation and upgrade activities will be performed all around the 27km ring. The schedule has been optimized in order to reduce the length of the shutdown (LS1) to 22 months (including hardware commissioning). The organization of the works is therefore essential to ensure a safe and reliable plan. This paper introduces the various activities to be performed and presents the schedule and the preparation process, including the operational safety aspects.

TUPFI033	Colliding During the Squeeze and β* Leveling in the LHC	luminosity, impedance, collider, optics	1415
	X. Buffat EPFL, Lausanne, Switzerland W. Herr, M. Lamont, T. Pieloni, S. Redaelli, J. Wenninger CERN, Geneva, Switzerland
	While more challenging operationally, bringing the beams into collisions during the β squeeze rather than after presents some advantages. The large tune spread arising from the non-linearity of head-on beam-beam interactions can damp impedance-driven instabilities much more efficiently than external non-linearity such as octupoles presently used in operation. Moreover, colliding during the squeeze allows to level the luminosity, optimizing the pile-up in the experiments without changing the longitudinal distribution of collisions. Operational issues are discussed and experimental results from the LHC are presented.

TUPFI077	Commissioning Progress of the RHIC Electron Lenses	electron, solenoid, proton, lattice	1526
	W. Fischer, Z. Altinbas, M. Anerella, M. Blaskiewicz, D. Bruno, W.C. Dawson, D.M. Gassner, X. Gu, R.C. Gupta, K. Hamdi, J. Hock, L.T. Hoff, R.L. Hulsart, A.K. Jain, P.N. Joshi, R.F. Lambiase, Y. Luo, M. Mapes, A. Marone, R.J. Michnoff, T.A. Miller, M.G. Minty, C. Montag, J.F. Muratore, S. Nemesure, D. Phillips, A.I. Pikin, S.R. Plate, P.J. Rosas, L. Snydstrup, Y. Tan, C. Theisen, P. Thieberger, J.E. Tuozzolo, P. Wanderer, S.M. White, W. Zhang BNL, Upton, Long Island, New York, USA
	Funding: Work supported by U.S. DOE under contract No DE-AC02-98CH10886 with the U.S. Department of Energy. In polarized proton operation, the RHIC performance is limited by the head-on beam-beam effect. To overcome these limitations two electron lenses were installed and are under commissioning. One lens uses a newly manufactured superconducting solenoid, in the other lens the spare superconducting solenoid of the BNL Electron Beam Ion Source is installed to allow for propagation of the electron beam. (This spare magnet will be replaced by the same type of superconducting magnet that is also used in the other lens during the 2013 shut-down.) We give an overview of the commissioning configuration of both lenses, and report on first results in commissioning the hardware and electron beam. We also report on lattice modifications needed to adjust the phase advance between the beam-beam interactions and the electron lenses, as well as upgrades to the proton instrumentation for the commissioning.

TUPME001	Effect of Self-consistency on Space Charge Induced Beam Loss	resonance, simulation, space-charge, emittance	1556
	G. Franchetti GSI, Darmstadt, Germany
	In long term storage space charge driven incoherent effect may lead to a slow beam diffusion that causes emittance growth and beam loss. However, when beam loss are relevant the full mechanism cannot be understood only driven by an incoherent effect. In this proceeding the issue of the self-consistency is discussed, and its impact presented for simplified examples and for the SIS100.

TUPWO019	A Local Achromatic Design of C-ADS MEBT2	emittance, linac, bunching, cavity	1922
	H. Geng, Z. Guo, Z. Li, C. Meng, S. Pei, J.Y. Tang IHEP, Beijing, People's Republic of China
	The accelerator of China Accelerator Driven Sub-critical system consists of two injectors to ensure its high reliability. The Medium Energy Beam Transport line-2 is an essential part of the accelerator to transport and match the beam from either injector to the main linac. This paper presents a local achromatic design, which uses four bending magnets, for CADS MEBT2. It is found that both transverse and longitudinal emittance growths can be well controlled below 15% from MEBT2 entrance to the exit of the following superconducting spoke-021 section. The beam dynamics of MEBT2 will be discussed and the multi-particle tracking results will also be shown.

TUPWO040	Asymmetric Energy Colliding Ion Beams in the EDM Storage Ring	ion, storage-ring, proton, dipole	1961
	I. Koop BINP SB RAS, Novosibirsk, Russia
	A possibility to bent equally two counter rotating ion beams by the crossed electric and magnetic fields is investigated. The first beam is polarized and its spin precession is adjusted to be synchronous with the velocity vector precession (a frozen spin method). The counter rotating unpolarized ion beam travels along the same orbit but with different velocity. Sensitive SQUID-type BPMs measure the vertical orbit difference of two beams. Later on this information is used to distinguish the EDM signal from the magnetic moment precession. Application of this approach to search of the EDM for proton, deuteron and helion is discussed.

TUPWO049	Automatic Correction of Betatron Coupling in the LHC using Injection Oscillations	coupling, injection, quadrupole, betatron	1979
	T. Persson, T. Bach, D. Jacquet, V. Kain, Y.I. Levinsen, E.H. Maclean, M.J. McAteer, P.K. Skowroński, R. Tomás, G. Vanbavinckhove CERN, Geneva, Switzerland R. Miyamoto ESS, Lund, Sweden
	The control of the betatron coupling at injection and during the energy ramp is critical for the safe operation of the tune feedback and for the dynamic aperture. In the LHC every fill is preceded by the injection of a pilot bunch with low intensity. Using the injection oscillations from the pilot bunch we are able to measure the coupling at each individual BPM. The measurement is used to calculate a global coupling correction. The correction is based on the use of two orthogonal knobs which correct the real and imaginary part of the difference resonance term f1001, respectively. This method to correct the betatron coupling has been proven successful during the normal operation of the LHC. This paper presents the method used to calculate the corrections and its performance.

WEODB102	Generating Polarization Controllable FELs at Dalian Coherent Light Source	FEL, polarization, electron, undulator	2071
	T. Zhang, H.X. Deng, D. Wang, Z.T. Zhao SINAP, Shanghai, People's Republic of China D.X. Dai, G.R. Wu, X.M. Yang, W.Q. Zhang DICP, Dalian, People's Republic of China
	Funding: 973 Program of China (2011CB808300), NSFC 11175240 and 11205234. The property of the FEL polarization is of great importance to the user community. FEL pulses with ultra-high intensity and flexible polarization control ability will absolutely open up new scientific realms. In this paper, several polarization control approaches are presented to investigate the great potential on Dalian coherent light source, which is a government-approved novel FEL user facility with the capability of wavelength continuously tunable in the EUV regime of 50-150 nm. The numerical simulations show that both circularly polarized FELs with highly modulating frequency and 100 microjoule level pulse energy could be generated at Dalian coherent light source. T. Zhang, et al., FEL Polarization Control Studies on Dalian Coherent Light Source, Chinese Physics C, 2013, to be published.
	Slides WEODB102 [6.131 MB]

WEOBB202	Ultra-fast Data Acquisition System for Coherent Synchrotron Radiation Based on Superconducting Terahertz Detectors	synchrotron, radiation, electron, storage-ring	2094
	C.M. Caselle, M. Hofherr, K.S. Ilin, V. Judin, A. Kopmann, A. Menshikov, A.-S. Müller, M. Siegel, N.J. Smale, P. Thoma, M. Weber, S. Wuensch KIT, Eggenstein-Leopoldshafen, Germany B.M. Balzer, S. Cilingaryan Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany
	The ANKA synchrotron radiation source located at the Karlsruhe Institute of Technology in Germany operates in the energy range between 0.5-2.5GeV and provides coherent synchrotron radiation. To resolve the ultra-short terahertz pulses emitted by a single bunch, thin YBCO superconducting film detectors have been developed. A response time of 45ps was determined as the FWHM at the output of the analog amplifier. A novel and high accuracy data acquisition architecture for sampling of the individual ultra-short terahertz pulses combined with real-time data processing based on GPUs for coherent synchrotron radiation is presented. The digitizer board is a made-in-house board designed for sampling of the fast pulse signals with pulse width between few tens of picosecond until 100ps. For each terahertz pulse five samples are acquired with a minimum sampling time of 3ps. A prototype setup with terahertz YBCO detectors, digitizer boards and the high-throughput FPGA framework has been successfully developed and tested at ANKA. The overview of the experimental setup including the YBCO detector technology and the preliminary results with single and multi-bunch filling pattern will be discussed.
	Slides WEOBB202 [2.416 MB]

WEPWA026	Mechanical Design of Shift Driving System for DEPU at SSRF	polarization, simulation, undulator	2187
	R.B. Deng, W.L. Chen, H.W. Du, Z.B. Yan, M. Zhang SINAP, Shanghai, People's Republic of China
	Double elliptically polarized undulator (DEPU) for a soft X-ray beamline for ARPES and PEEM is being built at SSRF. In DEPU, two EPUs with different period lengths have the roughly same magnet array lengths and share a common H style frame. The shift driving systems for polarization adjustment, which are set on top of the backing beams for the constraint of space, are sophisticated designed to assure position stability under longitudinal magnet force change. Finite-element analyses are also performed to guarantee the rigidity of the systems. The system performance is tested under full operation range and the results are described in this paper.

WEPWA028	Measurement and Research on Cryogenic Remanence of Chunks Permanent Magnet for Cryogenic Undulator	cryogenics, permanent-magnet, undulator, factory	2190
	Y.Z. He SINAP, Shanghai, People's Republic of China
	The higher-precision cryogenic remanence measurment technology and error for chunks permanent magnet were researched in china firstly (10-300K). Magnetic measurement tooling and magnetic field calculation and measurement method of cryogenic remanence measurement system of chunks permanent magnet for cryogenic undulator were optimized. Cryogenic calibration Hall probe were pasted on surface of domestic chunks permanent magnet(Nd2Fe14B: N52, N50M, etc.) and table magnetic field B of permanent magnet were measured, and after being converted, then cryogenic remanence of domestic chunks permanent magnet were obtained and cryogenic remanence variation of domestic chunks permanent magnet were researched. Cryogenic remanence measurement data were checked by pulse B-H tester and PPMS respectively, the results show that cryogenic remanence data has higher reliability. By this experiment, initial foundation were established for development of SSRF cryogenic undulator and for cryogenic remanence measurement and study of domestic other chunks permanent magnets.

WEPWA029	Undulator Chamber R&D for SXFEL	undulator, vacuum, free-electron-laser, laser	2193
	X. Hu, L. Yin SINAP, Shanghai, People's Republic of China
	The upcoming construction of Shanghai Soft X-ray Free Electron Laser Facility (SXFEL) will use 18 m small gap undulators. Each undulator is 3 meters long and will work at a minimum gap of 9 mm. This requires a vacuum chamber with an outer height of 8 mm and an elliptic inner aperture. The pressure inside of the chamber shall be less than 10^-5 Pa for the beam operation. An oxygen-free copper vacuum chamber was designed and a prototype was developed. This chamber includes three parts, a copper pipe manufactured by stretching, two flanges made of clad metal and a set of supports. The main fabrication procedure and the test results for the chamber prototype are described in this paper.

WEPWA032	The Feed-forward Control Design of Correction Coil Power Supply for SSRF EPU	EPICS, power-supply, undulator, insertion	2199
	Q. Yuan, M. Gu, G.Y. Jiang, R. Wang SINAP, Shanghai, People's Republic of China
	The SSRF Elliptically Polarized Undulator (EPU) has been in operation for about three years. The feed-forward control algorithm of correction coil power supply (CCPS) is implemented in the Input and Output Controller (IOC) based on VME. The correction current responds not fast enough to gap movement, mainly because the communication between IOC and digital CCPS taking up much time. This paper introduces one new feed-forward design, that is ,on the one hand, the CCPS current responds to both gap movement and shift movement according to 2D Look-up Table(LUT) by linear interpolation method. On the other hand, feed-forward control algorithm is carried out in the EPU controller, and the CCPS with fast control response is directly controlled by PLC through analog interface. Thus, the correction current respond well to gap and shift movement owing to leaving out communication time.

WEPWA043	Construction of Injector Test Facility (ITF) for the PAL XFEL	gun, emittance, laser, klystron	2220
	S.J. Park, H. J. Choi, T. Ha, J.H. Han, J.H. Hong, W.H. Hwang, H.-S. Kang, T.-H. Kang, D.T. Kim, J.M. Kim, S.-C. Kim, I.S. Ko, B.H. Lee, H.-S. Lee, W.W. Lee, C.-K. Min, Y.J. Park, Y.G. Son PAL, Pohang, Kyungbuk, Republic of Korea M.S. Chae POSTECH, Pohang, Kyungbuk, Republic of Korea
	Funding: Work supported by the Ministry of Education, Science and Technology (MEST) in Korea. An injector test facility (ITF) for the PAL-XFEL has been successfully constructed and its commissioning is under way. The facility is to demonstrate beam performances required by the PAL XFEL (beam energy of 139 MeV, projected rms emittance of < 0.5 mm mrad @ 200 pC, and beam repetition rate of 60 Hz) with good enough stabilities. We have constructed a dedicated building for the facility in which a radiation-shielding tunnel (19.2-m long, 3.5-m wide, and 2.4-m high inner space), a klystron-modulator gallery, a laser room, and a control room are installed. The injector consists of an in-house-developed photo-cathode rf gun, a 30-mJ Ti:Sa laser system, two accelerating structures (as well as two sets of klystron-modulator systems), and various diagnostics as well as magnets & instrumentations. The installation of a transverse deflecting cavity (S-band, 10-fs resolution) and a laser heater is scheduled in 2013. In this article we report on the facility construction and some of the early commisisoning results.

WEPWA053	Control System of In-vacuum Undulator in Taiwan Photon Source	EPICS, vacuum, undulator, insertion	2238
	C.Y. Wu, J. Chen, Y.-S. Cheng, P.C. Chiu, K.T. Hsu, C.Y. Liao NSRRC, Hsinchu, Taiwan
	Insertion device (ID) is a crucial component in third-generation synchrotron light sources, which can produces highly-brilliant, forward-directed and quasi-monochromatic radiation over a broad energy range for various experiments. In the phase I of the Taiwan Photon Source (TPS) project, seven IU22s (In-Vacuum Undulator) will be planned, constructed, and installed. The control system for IU22 is based on the EPICS architecture. The main control components include the motor with encoder for gap adjustment, trimming power supply for corrector magnets, ion pumpers and BA gauges for vacuum system, temperature sensors for ID environmental monitoring and baking, and interlock system (limit switches, emergency button) for safety. The progress of IU22 control system will be summarized in this report.

WEPWA054	Rejuvenation of Control System of the Undulator 50 in Taiwan Light Source	EPICS, undulator, insertion, insertion-device	2241
	C.Y. Liao, J. Chen, P.C. Chiu, K.T. Hsu, C.Y. Wu NSRRC, Hsinchu, Taiwan
	The Undulator 50 (U50) for Taiwan Light Source (TLS) was installed on March 1997 at NSRRC. It provides service for more than 15 years. Control system of U50 includes a PC running MS-DOS for local control. Motion controller contains two indexers with driver via RS-232 interface. It equip with IEEE-488 interface to connect to the VME system for remote access. The response time for command and reply is in the order of second, thus the throughput of the experiment for energy scan is time-consuming. New U50 control system will share the standard environment for insertion devices (ID) control for the Taiwan Photon Source (TPS) project. Ethernet based motion controller was chosen to drive motor drivers. All control functionality will coordinate by the cPCI EPICS IOC. To compatible with TLS existed control environment, a server program was develop to translate the protocol to EPICS PVs. All existed GUI of TLS still can be used. These improvements of control system for U50 are essential upgrading geared to avoid obsolescence of the control related parts, increase productivity and support on-the-fly experiments. The progress of the controls plan will be summarized in this report.

WEPWA060	The Kharkov X-ray Generator Facility NESTOR	storage-ring, electron, lattice, injection	2253
	A.A. Shcherbakov, V.P. Androsov, N. Ayzatsky, V.N. Boriskin, E.V. Bulyak, A.N. Dovbnya, P. Gladkikh, A.N. Gordienko, V.A. Grevtsev, A. Gvozd, V.E. Ivashchenko, A.A. Kalamayko, I.I. Karnaukhov, I.M. Karnaukhov, V.P. Kozin, V.A. Kushnir, V.P. Lyashchenko, V.S. Margin, N.I. Mocheshnikov, V.V. Mytrochenko, A. Mytsykov, I.M. Neklyudov, T.F. Nikitina, F.A. Peev, O.V. Ryezayev, V.L. Skirda, V.A. Skomorokhov, Y.N. Telegin, V.I. Trotsenko, A.Y. Zelinsky, O.D. Zvonarjova NSC/KIPT, Kharkov, Ukraine J.I.M. Botman TUE, Eindhoven, The Netherlands I.V. Drebot LAL, Orsay, France
	The last few years the sources of the X-rays NESTOR based on a storage ring with low beam energy and Compton scattering of intense laser beam are under design and development in NSC KIPT. The main task of the project is to develop compact intense X-ray generator on the base of relatively cheap accelerator equipment and up-to-date laser technologies. The paper is devoted to description of the last results on construction and commissioning of the facility.

WEPWO001	Power Couplers for XFEL	vacuum, site, pick-up, monitoring	2310
	W. Kaabi, M. El Khaldi, A. Gallas, P. Lepercq, C. Magueur, A. Variola, A. Verguet LAL, Orsay, France W.-D. Möller DESY, Hamburg, Germany
	The LAL contribution to the XFEL project will be the delivery of 800 power couplers to equip 100 Cry-modules. The LAL’s tasks consist on the industrial monitoring and coupler quality control at two different production sites, in addition to the RF conditioning at LAL of the 800 produced couplers. The RF conditioning and all the coupler preparation process will be held in a 70m2 ISO5 clean room. An RF power station delivering 5MW, allow 8 couplers conditioning in the same time. Being in production control side and also RF conditioning one, the aim of LAL is to reach the rate of 8 couplers delivery per week, after a rump up phase. The starting of Coupler mass production is scheduled for beginning 2013.

WEPWO004	Studies of Systematic Flux Expulsion in Superconducting Niobium	niobium, cavity, simulation, lattice	2316
	J.M. Vogt, J. Knobloch, O. Kugeler HZB, Berlin, Germany
	The quality factor Q0 that can be obtained in a superconducting cavity is known to depend on various factors like niobium material properties, treatment history and magnetic shielding. We believe that cooling conditions have an additional impact, as they appear to influence the amount of trapped flux and hence the residual resistance. We have constructed a test stand using niobium rods to study flux trapping. Here we can precisely control the temperature and approach Tc from below in the superconducting state. Although the sample remains in the superconducting state, a change in the amount of trapped flux is visible. The procedure can be applied repeatedly resulting in a significantly lowered level of trapped flux in the sample. Furthermore, simulations using the Radia software package for Mathematica developed by the ESR were used to better unterstand the measured changes in magnetic flux around the Sample. Applying a similar procedure for minimization of trapped magnetic flux to a superconducting cavity could allow for reduction of the magnetic contribution to the surface resistance and result in a significant improvement of Q0.

WEPWO011	In-vacuum Temperature Measurement of Niobium Components using Infrared Pyrometry during Electron Beam Welding Procedure	cavity, vacuum, electron, shielding	2334
	L. Monaco, P. Michelato, C. Pagani, D. Sertore INFN/LASA, Segrate (MI), Italy V. Battista, G. Corniani, M. Festa Ettore Zanon S.p.A., Schio, Italy
	Electron beam welding (EBW) is widely used in the construction of Niobium Superconducting RF cavities. The welding sequence of such a complex structure, foresees many welding operations. The welding parameters depend on many variables as the material thickness, but also on the component temperature before each weld. This paper presents a technique to measure the temperature of Nb components in vacuum during the EBW operation using an IR pyrometer placed outside the vacuum chamber through an appropriate vacuum viewport. With the current configuration the system can measure temperatures up to 350°C in the vacuum conditions of the EBW vacuum chamber (10-5-10^-6 mbar). The technique was used to optimize the time interval between each subsequent equatorial weld operation during Nb cavities production at Ettore Zanon, increasing the welding procedure reliability and decreasing the waiting time by control of the temperatures in the weld region. Moreover this technique can be generally used for in vacuum measurements of components from room temperature up to about 350 °C. Future developments are under way to make this technique compatible with UHV and increasing the measurement range.

WEPWO019	Development of Frequency Measurement Setup for ADS 650MHz and 1.3GHz Superconducting RF Cavities at IHEP	cavity, SRF, linac, simulation	2358
	S. Jin, J. Gao, Y. Liu, Z.C. Liu, J.Y. Zhai, T.X. Zhao, H.J. Zheng IHEP, Beijing, People's Republic of China
	The Accelerator Driven Sub-critical System (ADS) is under development in China, and the 650MHz β=0.82 superconducting RF cavity (SRF) has been chosen as a possible candidate to accelerate the proton bunches in the medium energy section from 360MeV to 1.5GeV [1]. In order to obtain quality management and quality assurance during fabrication, radio frequency measurements on parts and subassemblies of SRF cavities become a proper method [2]. In this paper, study on developing a new frequency measurement setup mainly for half cells, dumb-bells and end groups of ADS650MHz cavities at IHEP was reported. A digital pressure sense was assembled in the setup. Together with the simulation on the structural and frequency by ANSYS Workbench, a quantitative standard for the frequency measurement was built for the cavity fabrication. Since a 9-cell TESLA-Like cavity is also under study in the meantime, via a slight modification, the setup can be also used for it.

WEPWO025	Preliminary Design of 325 MHz Half-Wave Resonator	cavity, simulation, proton, heavy-ion	2369
	X.Y. Zhang, X. Chen, Z.Q. Li, Q. Ma, W.M. Pan, Y. Sun, G.W. Wang, Q.Y. Wang, B. Xu, G.Y. Zhao IHEP, Beijing, People's Republic of China
	Funding: This work is supported by the "Strategic Priority Research Program" of CAS. The Half-Wave Resonator (HWR) has been widely used in proton and heavy ion accelerators, for it has particular advantages of accelerating low energy charged particles. Preliminary design of a 325 MHz β=0.12 superconducting HWR cavity has been proposed at Institute of High Energy Physics (IHEP). The basic geometric parameters choices of the cavity are based upon theoretical model and numerical calculation, and then the RF performances are optimized by extensive electromagnetic simulations. In this paper, the detailed mechanical analysis, frequency control, and the considerations for fabrication of the 325 MHz HWR cavity are also presented.

WEPWO036	Conceptual Design of a Superfluid Superconducting Third Harmonic RF System for the SSRF Storage Ring	cavity, superconducting-cavity, cryogenics, synchrotron	2381
	H.T. Hou, J.F. Liu, Z.T. Zhao SINAP, Shanghai, People's Republic of China J.F. Liu Shanghai KEY Laboratory of Cryogenics & Superconducting RF Technology, Shanghai, People's Republic of China
	Harmonic cavity can improve the beam quality through bunch size lengthening which includes providing Landau damping, suppressing coupled bunch instability and microwave instability, enhancing the beam current per bunch besides the beam lifetime improvement. A passive third harmonic superconducting cavity operating at super fluid liquid helium has been proposed for the SSRF storage ring with compromise on the required harmonic voltage, limited installation space and dissipated cryogenic power. This paper will mainly present the conceptual design of the harmonic rf system including the requirement of SSRF, a brief review on beam dynamics of harmonic rf system and the harmonic cavity choice.

WEPWO043	IFMIF-EVEDA SRF Linac Couplers Test Bench	vacuum, linac, SRF, LLRF	2396
	D. Regidor, I. Kirpitchev, J. Molla, P. Méndez, A. Salom, M. Weber CIEMAT, Madrid, Spain M. Desmons, N. Grouas, P. Hardy, V.M. Hennion, H. Jenhani, F. Orsini CEA/IRFU, Gif-sur-Yvette, France
	The IFMIF-EVEDA SRF Linac is a cryomodule equipped with eight superconducting HWR cavities, operating at the frequency of 175 MHz and powered by 200kW CW RF couplers. Before assembling the couplers to the cryomodule, it is necessary to process them using high levels of RF power. In order to perform this conditioning, the power couplers must be connected to a RF network which is fed by an RF source and ended with a load or a short-circuit, depending on the conditioning mode to be applied. A test bench has been designed for the conditioning of the SRF LINAC couplers. The main component is the “test box”, a resonant cavity where two couplers will be assembled to transmit the 200 kW from the RF source to the appropriate termination. The test box includes a large pumping port allowing an efficient pumping of the entire vacuum volume limited by the coupler ceramic windows. Several diagnostics as light detectors, vacuum gauges and thermal transducers will provide information on the relevant parameters for the control of the RF conditioning process. In addition, a support frame has been designed to maintain the whole assembly and reduce the mechanical stress on the couplers.

WEPWO058	Recent Progress at Fermilab Controlling Lorentz Force Detuning and Microphonics in Superconducting Cavities	cavity, resonance, cryomodule, SRF	2438
	W. Schappert, Y.M. Pischalnikov Fermilab, Batavia, USA
	Funding: Work is supported by U.S. Department of Energy SRF cavities are susceptible to detuning by mechanical deformations induced by the Lorentz force and microphonics. Providing the RF overhead required to maintain the accelerating gradient in detuned cavities can increase both the capital and operating costs of superconducting accelerators. Recent work at Fermilab has shown that active vibration control using a piezo actuator can reduce both Lorentz Force detuning and microphonics to the point where negligible RF overhead is required to maintain the accelerating gradient.

WEPWO066	Frequency Control in the Cornell-ERL Main-Linac Cavity Production	cavity, niobium, target, LabView	2453
	V.D. Shemelin, B. Bullock, P.R. Carriere, B. Clasby, R. Eichhorn, B. Elmore, J.J. Kaufman, J. Sears CLASSE, Ithaca, New York, USA
	Funding: NSF award DMR-0807731 Cavity fabrication can be broken down into three main stages: deep-drawing cups, welding the cups in pairs to obtain “dumbbells” and end groups, and, finally, welding the obtained components into a completed cavity. Frequency measurements and precise machining were implemented after the second stage. A custom RF fixture and data acquisition system were used for this purpose. The system comprised of a mechanical press with RF contacts, a network analyzer, a load cell and custom LabVIEW and MATLAB scripts. To extract the individual frequencies of the cups from these measurements, algorithm of calculations was developed. Corrections for the ambient environment were also incorporated into the measurement protocol. Two 7-cell 1.3 GHz cavities were produced with high field flatness immediately after fabrication.

WEPWO082	Ferroelectric Based High Power Tuner for L-band Accelerator Applications	linac, cavity, vacuum, simulation	2486
	A. Kanareykin Euclid TechLabs, LLC, Solon, Ohio, USA S. Kazakov, V.P. Yakovlev Fermilab, Batavia, USA A.B. Kozyrev LETI, Saint-Petersburg, Russia E. Nenasheva Ceramics Ltd., St. Petersburg, Russia
	Funding: US Department of Energy With this paper, we present our recent breakthrough with a new fast ferroelectric tuner development. The tuner is based on BST(M) ferroelectric elements (ε~150), which are designed to be used as the basis for L-band accelerator components intended for ERL, ILC, Project X and other applications. These new ferroelectric elements are to be fabricated for the new fast active tuner for SC cavities that can operate in air at low biasing DC fields. Note there were no reliable results on the long-term piezo actuators operations in CW regime. Specific features of ERL, ILC and Project X accelerator technology and challenges of the designs are high magnitude and phase stability of its operations. Mechanical vibrations, or microphonics affect the SRF resonator, while the ferroelectric tuners have shown extremely high tuning speed. We have demonstrated successful mitigation of the residual effects on the ferroelectric-metal interface along with the acceptable level of the overall loss factor of the tuner element. A new concepts of a tuning element based on low dielectric constant ferroelectrics along with fabrication technology of these new BST(M) ferroelectric elements will be presented.

WEPEA010	Modeling Longitudinal Bunched Beam Dynamics in Hadron Synchrotrons using Scaled Fourier-Hermite Expansions	synchrotron, simulation, hadron, feedback	2513
	K. Gross, D.E.M. Lens TU Darmstadt, RTR, Darmstadt, Germany
	To devise control strategies and to analyze the stability of systems with feedback, a set of few ODEs describing the underlying dynamics is required. Numerical Fourier-Hermite solutions of the Vlasov equation have been studied for over fifty years. The idea to expand the distribution function in Fourier series in space and Hermite functions in velocity is transferred to the dynamics of bunched beams in hadron synchrotrons in this contribution. The Hermite basis is a natural choice for plasmas with Maxwellian velocity profile as well as for particle beams with Gaussian momentum spread. The Fourier basis used for spatially nearly uniform plasmas has to be adapted to bunched beams where the beam profile is not uniform in phase. This is achieved analogously to the deduction of the three term recursion relations to construct orthogonal polynomials, but applied to Fourier series with the weight function taken from the Hamiltonian. The resulting system of ODEs for the expansion coefficients of desired order - dependent on the number of functions retained - is checked against macro particle tracking simulations.

WEPEA038	Two and three Dimensional Models for Analytical and Numerical Space Charge Simulation	space-charge, linac, simulation, ion	2585
	S.N. Andrianov, N.V. Kulabukhova St. Petersburg State University, St. Petersburg, Russia
	In this article there is described an analytical approach to describe the self-field of two- and three dimensional ellipsoidal presentation of space charge distribution. The corresponding results can be evaluated in both numerical and the analytic presentation for some model distributions of charge. The corresponding results can be embedded in the Lie formalism used to describe the map for the beam dynamics. The corresponding linear and nonlinear maps are evaluated in terms of the matrix representation of the evolution operator of the beam. Appropriate solutions for nonlinear differential equations are based on a prediction-correction method (the converging recursive procedure). These solutions are compared with the Vlasov equation solutions. A special software package for the described approach is presented.

WEPEA041	Actions To Mitigate The Radiation Damage to Electronics at the LHC	shielding, radiation, hadron, civil-engineering	2591
	A.-L. Perrot, M.B.M. Barberan Marin, J.-P. Corso, K. Foraz, M. Lazzaroni, Y. Muttoni CERN, Geneva, Switzerland
	The level of flux of hadrons with energy in the multi MeV range expected from the collisions at the LHC interaction Points 1, 5 and 8 and from the collimation system at Point 7 will induce Single Event Errors (SEEs) in the standard electronics present in many of the control equipment installed in LHC underground. Furthermore, a risk of SEEs induced by thermal neutrons cannot be excluded. Such events would perturb the LHC operation, possibly leading to a stop of the machine. Main mitigation actions will be implemented during the first LHC Long Shutdown of 2013/2014 (LS1) to reduce the SEE occurrence. This paper summarizes the mitigation measures and their associated foreseen improvements in terms of SEEs. It presents the organization process and associated planning highlighting the impacts with the overall LHC LS1 planning and the main concerns during implementation.

WEPEA043	Working Point and Resonance Studies at the CERN PS	resonance, injection, octupole, focusing	2597
	A. Huschauer, M. Benedikt, H. Damerau, P. Freyermuth, S.S. Gilardoni, R. Steerenberg, B. Vandorpe CERN, Geneva, Switzerland
	The increase of luminosity demanded by the High Luminosity LHC (HL-LHC) requires an increase of beam intensity, which might result in instabilities appearing at injection energy in the CERN PS. Transverse head-tail instabilities have already been observed on operational LHC beams and a stabilizing mechanism as an alternative to linear coupling is currently being studied. It consists of reducing the mode number of the transverse oscillation by changing linear chromaticity and in succession completely suppressing the instability by a transverse damper system with appropriate bandwidth. Therefore, a chromaticity correction scheme at low energy exploiting the intrinsic possibilities offered by special circuits mounted on top of the main magnet poles, the Pole Face Windings (PFW), has been examined. The presence of destructive betatron resonances, which restrict the choice of the injection working point and the maximum acceptable tune spread, forms an additional limitation for high-brightness and high-intensity beams in the CERN PS. To improve the current working point control scheme, the influence of the P F W on the machine resonances is presented in this paper.

WEPEA044	RF Manipulations for Higher Brightness LHC-type Beams	injection, brightness, emittance, extraction	2600
	H. Damerau, A. Findlay, S.S. Gilardoni, S. Hancock CERN, Geneva, Switzerland
	In order to increase the transverse brightness of beams for the LHC, ever more complicated RF manipulations have been proposed in the PS machine in order to reduce the intensity demands per PS batch on the upstream PS Booster. Several schemes based on cascades of batch compression, bunch merging, as well as the more routine bunch splitting have been successfully commissioned and higher brightness beams have been delivered to the downstream accelerators for measurement. Despite all this complexity, longitudinal and transverse beam quality are well preserved. In addition, to fully profit from the brightness of all four PS Booster rings, the injection of twice 4 bunches into harmonic 9 buckets in the PS has been made operational as an alternative to the usual double-batch transfer of 4+2 bunches into harmonic 7. This paper summarizes the new beam production schemes, their implementation in the PS low-level RF system and the experimental results.

WEPEA055	Quantitative Evaluation of Trapping and Overall Efficiency for Simple Models in One-degree of Freedom	resonance, simulation, synchrotron, extraction	2630
	C. Hernalsteens, C. Frye, M. Giovannozzi CERN, Geneva, Switzerland A. Bazzani Bologna University, Bologna, Italy
	A key ingredient for the Multi-Turn Extraction at the CERN Proton Synchrotron is the beam trapping in stable islands of transverse phase space. The control of the trapping process is essential for the quality of the final beam in terms of intensity sharing and emittance. In this paper, a method allowing an analytical estimation of the fraction of beam trapped into stable islands as a function of the Hamiltonian parameters is presented for a very simple model of the dynamics (pendulum) and is extended to the case of the interpolating Hamiltonian of the Hénon model, the latter being a good 2D model of the MTE dynamics. The analytical results are compared with numerical simulations. Additional numerical simulations are presented for the minimum trapping amplitude and a fitted model is proposed. Results are discussed in detail.

WEPEA063	Upgrades and Consolidation of the CERN AD for Operation during the Next Decades	target, antiproton, electron, vacuum	2654
	T. Eriksson, M. E. Angoletta, L. Arnaudon, J.A. Baillie, M. Calviani, F. Caspers, L.V. Joergensen, R. Kersevan, G. Le Godec, R. Louwerse, M. Ludwig, S. Maury, A. Newborough, C. Oliveira, G. Tranquille CERN, Geneva, Switzerland
	As the ELENA project is now well underway, focus is turned to the Antiproton Decelerator (AD) itself. Most of the machine’s key components are in operation since more than 25 years and a substantial consolidation program is now being launched in view of continued operation beyond 2025. Over the course of the next few years a progressive consolidation of the AD-Target area, the AD-ring and all associated systems will take place. Several investigations have recently been performed in the target area with the objective of establishing the radiation environment and the sensitivity of the antiproton production to potential misalignment of the production elements. Identification of reliability and serviceability issues of the AD-ring components and associated systems has been done and will continue during the 2013 shut-down. Planned and ongoing consolidation activities are also discussed with emphasis on stochastic and electron beam cooling, instrumentation, RF systems, vacuum, magnets, power converters and beam transfer equipment.

WEPEA065	Beam Tests and Plans for the CERN PS Booster Wideband RF System Prototype	cavity, feedback, LLRF, booster	2660
	M.M. Paoluzzi, M. E. Angoletta, A. Findlay, M. Haase, M. Jaussi CERN, Geneva, Switzerland
	In the framework of the LHC Injectors Upgrade project (LIU) and in view of a complete replacement of the existing CERN PS Booster (PSB) RF systems, a prototype cavity has been installed beginning of 2012 in the machine. This modular, wideband (0.5 / 4 MHz), Finemet® loaded system uses solid-state power stages and includes fast RF feedback for beam loading compensation. In depth studies have been performed during 2012 to evaluate the system interaction with the new low-level digital electronics, its ability to accelerate the beam and cope with high beam intensity. The encouraging results suggest that this innovative approach can indeed be used to replace all the existing PSB RF systems but additional testing with a full scale prototype is required. This paper reports about the project status, the achieved results, the encountered difficulties and the foreseen prototype completion in preparation during 2013.

WEPEA069	Review of the Drive Beam Stabilization in the CLIC Test Facility CTF3	feedback, linac, klystron, low-level-rf	2666
	A. Dubrovskiy, L. Malina, P.K. Skowroński, F. Tecker CERN, Geneva, Switzerland T. Persson Chalmers University of Technology, Chalmers Tekniska Högskola, Gothenburg, Sweden
	CTF3 is a Test Facility focusing on beam-based studies of the key concepts of the Compact Linear Collider CLIC. Over the past several years many aspects the CLIC two-beam acceleration scheme were studied in CTF3, including the crucial issue of drive beam stability. The main sources of drifts and instabilities have been identified and mitigated, helping to improve the machine performance and showing significant progress towards the experimental demonstration of the very stringent requirements on current, energy and phase stability needed in CLIC. In this paper, the more effective techniques and feed-backs are summarized. The latest measurements on beam stability are reported and their relevance to CLIC is discussed.

WEPFI002	Acceptance Tests for the Spiral2 SC Linac RF Power Systems	cavity, linac, impedance, insertion	2702
	M. Di Giacomo GANIL, Caen, France
	Funding: This activity received founds from the EuCard RF Tech program The Spiral2 SC linac uses solid state amplifiers ranging from 2,5 to 19 kW and external circulators to drive normal and superconducting cavities at 88.0525 MHz. The project has no manpower for in house development and all power devices are ordered to commercial companies. Robust acceptance tests have therefore been defined to check reliability with respect to our application. The papers describes the tests procedure and results on our first units.

WEPFI005	Simulations and RF Measurements of the Fundamental and Higher Order Modes of the ThomX 500 MHz Cavity	cavity, HOM, impedance, feedback	2711
	M. El Khaldi, I.V. Drebot, P. Lepercq, R. Marie, B. Mercier, T. Roulet, A. Variola, F. Wicek LAL, Orsay, France H.D. Dias, M.D. Diop, M.E. El Ajjouri, R. Lopes, A. Loulergue, P. Marchand, F. Ribeiro, R. Sreedharan SOLEIL, Gif-sur-Yvette, France
	The RF system of the ThomX* storage ring consists in a 500 MHz single cell copper cavity of the ELETTRA type, powered with a 50 kW CW solid state amplifier, and the associated Low Level RF feedback and control loops. The low operating energy of 50 – 70 MeV makes the impedances of the cavity higher order modes (HOMs) particularly critical for the beam stability. Their parasitic effects on the beam can be cured by HOM frequency shifting techniques, based on a fine temperature tuning and a dedicated plunger. A typical cavity temperature stability of ± 0.05°C within a range from 35 up to 80 °C can be achieved by a precise control of its water cooling temperature. On the other hand, the tuning of the cavity fundamental mode is achieved by changing its axial length by means of a mechanical tuner. In order to insure a fine control of the HOM frequencies, a good knowledge of their characteristics is mandatory. The main parameters of the fundamental and of the HOMs up to 4 GHz have been calculated using the HFSS and CST MWS codes. Preliminary measurements results have been obtained and show a good agreement with the simulations. * A.Variola, “The ThomX Project”, Proceedings of IPAC2011, San Sebastián, Spain

WEPFI007	Amplitude, Phase and Temperature Stabilization of the ELSA RF System	cavity, LLRF, HOM, feedback	2717
	D. Sauerland, W. Hillert, A. Roth, M. Schedler ELSA, Bonn, Germany D. Teytelman Dimtel, San Jose, USA
	In the stretcher ring of the accelerator facility ELSA electrons are accelerated to a maximum energy of 3.2 GeV applying a fast energy ramp of up to 6 GeV/s. In order to be able to offer higher external beam currents one has to increase the current of the internal beam in ELSA accordingly. The beam current is limited due to excitation of multi bunch instabilities which are mainly caused by higher order modes of the two PETRA cavities used for particle acceleration in the stretcher ring. To control the resonance frequency of these modes, a variable bypass of the cavities' cooling system has been installed which allows a stabilization of their temperature. With this modification, it is possible to vary the temperature of the cavities between 26 °C and 65 °C and thus to shift the higher order modes by hundreds of kHz in frequency. Additionally, first operational studies with a prototype of a FPGA based LLRF system (Dimtel) have been performed which in future will be used to stabilize the amplitude and phase of the accelerating RF fields of the cavities.

WEPFI026	Design and Commissioning of the RF System of CYCIAE 14 Cyclotron	cyclotron, cavity, low-level-rf, resonance	2759
	Z.G. Yin, B. Ji, Y. Lei, P.Z. Li, G.F. Song, C. Wang, T.J. Zhang, Z.L. Zhao CIAE, Beijing, People's Republic of China
	The RF system of CYCIAE-14 consists of a set of 20kW amplifier, two 1/4λ RF cavities connected in central region, the transmission line and a set of LLRF system. The LLRF system, based on DDS and DSP, has achieved the close-loop adjustment of accelerating voltage and the resonant frequency. The RF system design for CYCIAE-14 was started in 2010, and the fabrication of the major equipments was finished in 2011. The installation and commissioning was completed in early 2012, satisfying the design requirements. This article describes the design of the RF system, and summarizes the difficulties encountered in the process of manufacture, installation and commissioning. Some of the problems caused by the transmission line and the RF leakage are analyzed, followed by the measures taken to solve these problems.

WEPFI028	RF System of the CSNS Synchrotron	cavity, LLRF, feedback, synchrotron	2765
	H. Sun, W.L. Huang, X. Li, W. Long, H. Shi, C.L. Zhang, F.C. Zhao IHEP, Beijing, People's Republic of China
	The accelerator of China Spallation Neutron Source (CSNS) consists of a H− linac and a rapid cycling synchrotron (RCS). The protons injected into the RCS will be accelerated from 81MeV to 1.6GeV by the Ring RF system providing a maximum accelerating voltage of 165kV. The RF frequency sweeps from 1.02 MHz to 2.44 MHz. with a repetition rate of 25Hz. The ferrite-loaded RF cavities will be used in the ring RF system. Each cavity has own RF power tube amplifier, bias current supply and full digital LLRF control loops. The R&D of ring rf system have been completed, it compose of the prototypes of a full size ferrite loaded RF cavity, a high power tetrode amplifier, a switching type bias supply of 3000A and a full digital embedded controller of LLRF. CSNS ring RF system design and the results of the R&D will be described in this paper.

WEPFI041	Design of the RF System for the Accelerator Complex of Rare Isotope Science Project	cavity, LLRF, rfq, rf-amplifier	2794
	J. Han, O.R. Choi, J.-W. Kim IBS, Daejeon, Republic of Korea C.K. Hwang KAERI, Daejon, Republic of Korea
	The rare isotope beam facility planned in Korea utilizes superconducting linear accelerators and a cyclotron to accelerate heavy-ion and proton beams, in which an RFQ in the injection line and superconducting cavities are the main rf components. The RF systems to power the cavities and to control the system at the low level have been designed so as to acquire high-quality beam with precise controls of rf amplitude and phase. The superconducting cavity is sensitive to various perturbations like mechanical vibration and Lorentz force detuning due to narrow bandwidth. We plan to use the rf amplifier system based on solid state device for superconducting cavities, and a tetrode tube for the final stage of RF amplifier of the RFQ accelerator. An LLRF system to control the amplitude and phase, which was built and tested on a quarter-wave resonator, will be modified to control a superconducting cavity. We plan to test the LLRF system in the superconducting rf facility abroad.

WEPFI042	Installation and Operation of the RF System for the 100 MeV Proton Linac	linac, klystron, LLRF, proton	2797
	K.T. Seol, Y.-S. Cho, D.I. Kim, H.S. Kim, H.-J. Kwon, Y.-G. Song KAERI, Daejon, Republic of Korea
	Funding: This work was supported by the Ministry of Education, Science and Technology of the Korean Government. The RF system of the 100MeV proton linac for 1st phase of KOMAC has been installed at the Gyeong-ju site. Nine sets of LLRF control system and the HPRF system including 1MW klystrons, circulators and waveguide components have been installed at the klystron gallery, and four high voltage converter modulators has been installed at the modulator room. A RF reference system distributing 300MHz LO signal to each RF control system has also been installed with a temperature control system. The requirement of RF field control is within ± 1% in RF amplitude and ± 1 degree in RF phase, and the operation of RF system will start at the end of this year after installation. The installation and operation of the RF system for the 100MeV proton linac are presented in this paper.

WEPFI043	S-band High Stability Solid State Amplifier for 10 GeV PAL-XFEL	LLRF, FEL, klystron, monitoring	2800
	W.H. Hwang, J.Y. Huang, H.-S. Kang, H.-S. Lee, W.W. Lee PAL, Pohang, Kyungbuk, Republic of Korea
	In PAL, We are constructing a 10GeV PxFEL project. The output power of the klystron is 80 MW at the pulse width of 4 ㎲ and the repetition rate of 60 Hz. And the specifications of the rf phase and amplitude stability are 0.05 degrees(rms) and 0.05%(rms) respectively. The SSA(Solid State Amplifier) is used for driver of 80MW Klystron. The output power of SSA is 800W. Also, the measured rf stability of SSA output is 0.03 degrees rms and 0.025 % rms. This paper describes the microwave system and the SSA for the PxFEL.

WEPFI056	Study of the Thermo-Mechanical Behavior of the CLIC Two-Beam Modules	alignment, RF-structure, linac, collider	2818
	F. Rossi, R. Mondello, G. Riddone CERN, Geneva, Switzerland D. Gudkov, A. Samoshkin JINR, Dubna, Moscow Region, Russia I. Kossyvakis National Technical University of Athens, Zografou, Greece K. Österberg HIP, University of Helsinki, Finland
	The final luminosity target of the Compact LInear Collider (CLIC) imposes a micron-level stability of the two-meter repetitive two-beam modules constituting the main linacs. Two-beam prototype modules have been assembled to extensively study their thermo-mechanical behaviour under different operation modes. The power dissipation occurring in the modules will be reproduced and the efficiency of the corresponding cooling systems validated. At the same time, the real environmental conditions present in the CLIC tunnel will be studied. Air conditioning and ventilation systems will be installed in the dedicated laboratory. Air temperature will be varied from 20 to 40 °C, while air flow rate will be regulated up to 0.8 m/s. During all experimental tests, the alignment of the RF structures will be monitored to investigate the influence of power dissipation and air temperature on the overall thermo-mechanical behaviour. This test program will allow for better understanding the behaviour of CLIC modules and the results will be propagated back to both numerical modelling and engineering design.

WEPFI060	Planar Balun Design with Advanced Heat Dissipation Structure for kW Level Solid-state Amplifier Module Development	coupling, impedance, storage-ring, klystron	2830
	T.-C. Yu, L.-H. Chang, M.H. Chang, L.J. Chen, F.-T. Chung, M.-C. Lin, Y.-H. Lin, Z.L. Liu, C.H. Lo, M.H. Tsai, Ch. Wang, T.-T. Yang, M.-S. Yeh NSRRC, Hsinchu, Taiwan
	The power level of solid-state amplifier is continuously growing for advanced accelerator application as the RF power source. Huge amount of solid-state power amplifier (SSPA) modules can contribute several hundreds of kW RF power with high redundancy and reliability. However, with the increasing desire of RF power of single RF station, too much power modules would adversely cause larger area occupation and higher maintenance cost and complexity. Therefore, with the advancement of the RF power on single SSPA, the overall system design and configuration would become much simple and compact. However, the increasing RF of single SSPA would also bring the thermal problem at its chip as well as the output power combining balun. In this paper, kW range SSPA is developed with the novel planar balun structure with good thermal expansion property. With such new planar balun design, the SSPA can operate stably with above 1kW output RF power.

WEPFI061	Petra Cavity Vacuum RF Condition with Field Balance Mechanism for TPS Storage Ring in NSRRC	cavity, coupling, vacuum, storage-ring	2833
	T.-C. Yu, L.-H. Chang, M.H. Chang, L.J. Chen, F.-T. Chung, M.-C. Lin, Y.-H. Lin, Z.L. Liu, C.H. Lo, M.H. Tsai, Ch. Wang, T.-T. Yang, M.-S. Yeh NSRRC, Hsinchu, Taiwan
	In the first stage commissioning of TPS (Taiwan Photon source) storage ring in NSRRC, two room temperature Petra cavities will be used. At this commission stage, 100mA with 950keV beam loss is estimated to have 47.5kW beam loss for each cavity. In the meanwhile, the cavity loss at the specified 1.2MV of each cavity will be about 50kW. Therefore, coupling coefficient of 2 is required. However, the initial design specification of Petra cavity has only beta of about 1.7. Hence, the modification of the input coupler is done with the enhancement of its beta as well as advanced water cooling for some heat point. Besides, due to the two-tuner system of Petra cavity, special field-balance tuner control system is also developed. In RF condition for better vacuum up to 1.4MV, some modification of the tuner mechanical structure is also done to reach high vacuum condition (lower than 5*10^-9 Torr) for storage ring requirement.

WEPFI063	Progress on the ISIS Synchrotron Low Power RF System Upgrade	cavity, synchrotron, acceleration, proton	2839
	A. Seville, D.B. Allen, D. Bayley, N.E. Farthing, I.S.K. Gardner, R.J. Mathieson STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom W.L. Huang IHEP, Beijing, People's Republic of China
	The ISIS synchrotron at the Rutherford Appleton Laboratory in the UK now routinely uses a dual harmonic RF system to accelerate beam currents in excess of 230 uA to operate two target stations simultaneously. To give more stable control of the RF voltage at each of the fundamental (1RF) and second harmonic (2RF) cavities, changes have been made to the low power RF (LPRF) control systems. A new FPGA based master oscillator has been implemented using a National Instruments FlexRIO module. The replacement master oscillator has been tested with beam for the first time. This paper reports on the tests of the FlexRIO master oscillator and describes plans for the gradual replacement of the remaining parts of the LPRF system.

WEPFI066	The RF System for the MICE Experiment	cavity, LLRF, diagnostics, linac	2848
	K. Ronald, A.J. Dick, C.G. Whyte USTRAT/SUPA, Glasgow, United Kingdom P.A. Corlett STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom A.J. DeMello, D. Li, S.P. Virostek LBNL, Berkeley, California, USA A.F. Grant, A.J. Moss, C.J. White STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom P.M. Hanlet IIT, Chicago, Illinois, USA C. Hunt, K.R. Long, J. Pasternak Imperial College of Science and Technology, Department of Physics, London, United Kingdom T.H. Luo, D.J. Summers UMiss, University, Mississippi, USA A. Moretti, R.J. Pasquinelli, D.W. Peterson, R.P. Schultz, J.T. Volk Fermilab, Batavia, USA P.J. Smith Sheffield University, Sheffield, United Kingdom T. Stanley STFC/RAL, Chilton, Didcot, Oxon, United Kingdom Y. Torun Illinois Institute of Technology, Chicago, IL, USA
	The International Muon Ionisation Cooling Experiment (MICE) is designed to demonstrate the effectiveness of ionisation cooling to reduce the phase space footprint of a muon beam, principally to allow the subsequent acceleration of muons for next generation colliders and/or neutrino factories. The experiment (and indeed any subsequent accelerator cooling channel based on the same principles) poses certain unusual requirements on its RF system, whilst the precision measurement of the ionisation cooling process demands special diagnostics. This paper shall outline the key features of the RF system, including the LLRF control, the power amplifier chain, distribution network, cavities, tuners and couplers, all of which must operate in a high magnetic field environment. The RF diagnostics which, in conjunction with the other MICE diagnostics, shall allow detailed knowledge of the amplitude and phase of the acceleration field during the transit of each individual Muon shall also be outlined.

WEPME002	Fast Orbit Feedback at BESSY-II: Performance and Operational Experiences	feedback, booster, status, injection	2920
	R. Müller, T. Birke, M. Diehn, D.B. Engel, B. Franksen, R. Görgen, P. Kuske, R. Lange, I. Müller, A. Schälicke, G. Schindhelm HZB, Berlin, Germany
	At the 3rd generation light source BESSY II the first phase of a fast orbit feedback system() has been completed and put into operation in 2012. In this first phase the aim was to achieve noise suppression in the 1Hz to several 10Hz range, mostly avoiding expensive upgrades to existing hardware, such as beam position monitors and the CAN based setpoint transmission to the power supplies. Only the power supplies were replaced with newer, faster versions. This paper describes the capability of the phase-I FOFB with respect to beam motion transient suppression, low frequency damping and high frequency noise generation as well as aspects of operational integration and stability. Müller, R. et. al.: Installing a Fast Orbit Feedback at BESSY. IPAC 10, Kyoto, Japan, 23 - 28 May, 2010., p. 2749-2751
	Poster WEPME002 [2.720 MB]

WEPME004	A Digital Beam-Phase Control System for a Heavy-Ion Synchrotron with a Double-Harmonic Cavity System	cavity, synchrotron, feedback, dipole	2926
	J. Grieser, D.E.M. Lens TU Darmstadt, RTR, Darmstadt, Germany U. Hartel TEMF, TU Darmstadt, Darmstadt, Germany H. Klingbeil, U. Laier, K.-P. Ningel, S. Schäfer, B. Zipfel GSI, Darmstadt, Germany
	Funding: Funded by GSI Helmholtzzentrum für Schwerionenforschung GmbH For the new Facility for Antiproton and Ion Research (FAIR) at GSI Helmholtzzentrum für Schwerionenforschung GmbH, the heavy-ion synchrotron SIS18 will be operated with a double-harmonic cavity system. The second cavity, running at twice the fundamental RF frequency, is used to lengthen the bucket which introduces nonlinearities to the control system. To damp longitudinal rigid dipole oscillations a digital feedback system consisting of a filter and an integrator is used. For the existing single-harmonic setup an FIR-filter is implemented which realizes a multiple bandpass filter with the first passband close to the synchrotron frequency. Both, the feedback gain and the passband frequency of the filter depend on the actual value of the synchrotron frequency. It was shown by simulations and in an experiment that this setup can be transferred to a double-harmonic cavity system obtaining similar results for the region of stable feedback parameters, if the oscillation frequency of the bunch barycenter** is considered instead of the synchrotron frequency of a linearized bucket. In this contribution the results of the simulation and the experiment are presented and compared. Klingbeil et al.: Phys. Rev. Special Topics - Accelerators and Beams 14, 102802, 2011 Klingbeil et al.: IEEE Trans. on Nucl. Science, Vol. 54, No. 6, 2007 **Grieser et al.: Proc. 3rd IPAC, 2012

WEPME005	Pulsed RF Control for the P-Linac Test Stand at FAIR	linac, cavity, proton, antiproton	2929
	P. Nonn, U. Bonnes, C. Burandt, F. Hug, M. Konrad, N. Pietralla TU Darmstadt, Darmstadt, Germany R. Eichhorn Cornell University, Ithaca, New York, USA H. Klingbeil, G. Schreiber, W. Vinzenz GSI, Darmstadt, Germany H. Klingbeil TEMF, TU Darmstadt, Darmstadt, Germany
	Funding: Supported through BMBF contract no. 06DA9024I The p-linac will be a dedicated proton injector for antiproton production at FAIR (GSI Darmstadt). It will provide a 70 MeV/70 mA pulsed proton beam with a duty cycle of about 10^-4. Therefore the RF of the normal conducting, coupled CH cavities* will be pulsed, too. In order to test the operation of those cavities, a test stand is under construction at GSI. The RF control hard- and software for the test stand is developed at TU Darmstadt. It is based on the digital low level RF control system, which is operational at the S-DALINAC*. Hardware as well as software had to be customized, in order to achieve pulsed operation within the given limits. These customizations as well as measurements from pulsed operation will be presented. R. Brodhage et al. Development and Measurements on a Coupled CH Proton Linac for FAIR, IPAC'10 **M. Konrad et al. Digital base band rf control system for the… , PRL ST Accel. & Beams 15

WEPME008	Precision LLRF Controls for the S-Band Accelerator REGAE	laser, gun, LLRF, electron	2938
	M. Hoffmann, H. Kay, U. Mavrič, H. Schlarb, Ch. Schmidt DESY, Hamburg, Germany W. Jałmużna, T. Kozak, A. Piotrowski TUL-DMCS, Łódź, Poland
	The linear accelerator REGAE (Relativistic Electron Gun for Atomic Exploration) at DESY delivers electron bunches with a few femtosecond duration for time-resolved experiments of material structure in pump-probe configuration. To achieve the desired 10 fs resolution, the Low Level RF controls for the normal conducting S-band cavities must provide field stability of 0.01% in amplitude and of 0.01deg in phase. To achieve these demanding stability a recently developed LLRF controller based on the Micro-Telecommunications Computing Architecture (MTCA.4) have been installed and commission. In this paper, we report on measurement performance of the LLRF system, the achieved stability and current limitations.

WEPME009	Recent Developments of the European XFEL LLRF System	LLRF, cavity, laser, beam-loading	2941
	Ch. Schmidt, G. Ayvazyan, V. Ayvazyan, J. Branlard, L. Butkowski, M.K. Grecki, M. Hoffmann, T. Jeżyński, F. Ludwig, U. Mavrič, S. Pfeiffer, H. Schlarb, H.C. Weddig, B.Y. Yang DESY, Hamburg, Germany P. Barmuta, S. Bou Habib, K. Czuba, M. Grzegrzółka, E. Janas, J. Piekarski, I. Rutkowski, D. Sikora, L. Zembala, M. Żukociński Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland W. Cichalewski, K. Gnidzińska, W. Jałmużna, D.R. Makowski, A. Mielczarek, A. Napieralski, P. Perek, A. Piotrowski, T. Pożniak, K.P. Przygoda TUL-DMCS, Łódź, Poland S. Korolczuk, I.M. Kudla, J. Szewiński NCBJ, Świerk/Otwock, Poland K. Oliwa, W. Wierba IFJ-PAN, Kraków, Poland
	The European XFEL is comprised of more than 800 TESLA-type super-conducting accelerator cavities which are driven by 25 high-power multi-beam klystrons. For reliable, reproducible and maintainable operation of linac, the LLRF system will process more than 3000 RF channels. Beside the large number of RF channels to be processed, stable FEL operation demands field stability better than 0.010deg in phase and 0.01% in amplitude. To cope with these challenges the LLRF system is developed on MTCA.4 platform. In this paper, we will give an update of the latest electronics developments, advances in the feedback controller algorithm and measurement results at FLASH.

WEPME010	Patient-specific Intensity-modulation of a Slowly Extracted Beam at the HIT Synchrotron	feedback, ion, synchrotron, extraction	2944
	C. Schömers, E. Feldmeier, Th. Haberer, J. Naumann, R.E. Panse, A. Peters HIT, Heidelberg, Germany
	Since 2009 more than 1100 tumour patients have been treated at the Heidelberg Ion Therapy-Centre (HIT). The HIT synchrotron produces a library of energy, focus and intensity-variable pencil beams used to deliver dose distributions of utmost conformity to irregularly shaped target volumes. The required number of particles for each volume element of the tumour, which can vary by more than two magnitudes, is applied using the rasterscan technology. The irradiation-time and thus the patient throughput are highly sensitive to the achieved spill-structure driven by RF-Knockout extraction. Presently unfavourable fluctuations of the extracted intensity due to inhomogeneous phase space distribution of the beam are present. Recently a feedback-loop coupling the dose-defining ionisation chamber in front of the patient with the RF-Exciter was implemented allowing for the adaptation of the extracted intensity to the patient-specific treatment plan in real-time. The technical implementation and the impact on the clinical operation will be discussed.

WEPME013	Development and Test of a Fully Automated PkQl Control Procedure at KEK STF	cavity, LLRF, feedback, klystron	2950
	M. Omet, A. Kuramoto Sokendai, Ibaraki, Japan H. Hayano, T. Matsumoto, S. Michizono KEK, Ibaraki, Japan
	In order to operate the cavities near their maximum gradients, cavity input (Pk) and cavity loaded Q (QL) should be controlled individually (PkQL control) at the International Linear Collider (ILC). A manual PkQL operation procedure was developed and performed at the linear electron accelerator at the Superconducting RF Test Facility (STF), in which the beam is accelerated up to 40 MeV by two superconducting 9-cell TESLA type L band cavities. The cavity gradients were set to 16 MV/m and 24 MV/m with QL values of 110⁶ and 3·10⁶. A 6.2 mA beam with a pulse length of 154 us was used. The field stabilities in amplitude were 0.160% and 0.097% for the cavities and 0.016% for the vector sum. The stabilities without beam are 0.057% and 0.054% for the cavities and 0.009% for the vector sum. For stability improvement during beam transient an adaptive beam feedforward for beam loading compensation is under development. So far an amplitude field stability of 0.013% for the vector sum was achieved at cavity gradients of 15 MV/m and 25 MV/m (no PkQL control) during a 6.8 mA beam with a pulse length of 123 us. Furthermore a fully automated PkQL control procedure is currently developed and tested.
	Poster WEPME013 [0.647 MB]

WEPME014	Progress in Development of New LLRF Control System for SuperKEKB	cavity, klystron, LLRF, pick-up	2953
	T. Kobayashi, K. Akai, K. Ebihara, A. Kabe, K. Nakanishi, M. Nishiwaki, J.-I. Odagiri KEK, Ibaraki, Japan H. Deguchi, K. Harumatsu, K. Hayashi, T. Iwaki, J. Mizuno, J. Nishio, M. Ryoshi Mitsubishi Electric TOKKI Systems, Amagasaki, Hyogo, Japan
	For the SuperKEKB project, a new LLRF control system was developed to realize high accuracy and flexibility. It is an FPGA-based digital RF feedback control system using 16-bit ADC's, which works on the μTCA platform. The FPGA boards control accelerating cavity fields and cavity tuning, and the EPICS-IOC is embedded in each of them. The CSS-BOY was adopted for a user interface of our system. High power test of the new LLRF control system was performed with the ARES Cavity of KEKB. The obtained feedback control stability with a klystron drive was sufficient as well as the low-level evaluation result. And auto tuner control also worded successfully. The start-up sequencer program for the cavity operation and auto-aging program also worked very well. The temperature characteristics of the system depend largely on band-pass filters (BPF). We tried to tune the BPF to reduce the temperature coefficient. Consequently the temperature dependence was improved to satisfy the required stability.

WEPME015	Evaluation of the Superconducting LLRF system at cERL in KEK	LLRF, cavity, coupling, linac	2956
	F. Qiu, D.A. Arakawa, H. Katagiri, T. Matsumoto, S. Michizono, T. Miura, T. Miyajima, K. Tsuchiya KEK, Ibaraki, Japan
	A low level RF (LLRF) design is being currently developed within the compact Energy Recover Linac (cERL) at KEK. One challenging task is to achieve the high amplitude and high phase stability required by the accelerating fields of up to 0.1% and 0.1°, respectively. To improve the performance of the LLRF system, a gain scanning experiment for determining the optimal controller gain was carried out on the cERL. Furthermore, as a substitute for the traditional PI controller, a more robust H∞-based multiple input multiple output (MIMO) controller was realized. This controller requires more detailed system information (transfer function or state equation), which can be acquired by using modern system identification methods. In this paper, we describe the current status of these experiments on the cERL.

WEPME016	Recent Progress of a Laser-based Alignment System at the KEKB Injector Linac	laser, alignment, linac, feedback	2959
	T. Suwada, M. Satoh KEK, Ibaraki, Japan K. Minoshima, S. Telada AIST, Tsukuba, Japan
	A new laser-based alignment system is under development in order to precisely align accelerator components with a precision level of ±0.1 mm along an ideal straight line at the KEKB injector linac. The high-precision alignment system is strongly required for the Super B-factory at KEK. The laser-based alignment system comprises a He-Ne laser source and optical components for delivering the laser beam, and silicon photodetectors. The laser-based alignment system aligns a misalignment of a girder unit for accelerating structures while accelerator components on the girder unit are aligned with another laser tracker system with a similar precision level. A new PC-based feedback system for the laser pointing stability has been introduced in order to stabilize the transverse laser positions at the photodetector. The experimental results show that although the laser pointing stability is easily disturbed by environmental factors without the feedback system, it has been successfully applied to control the laser pointing stability within a few ten-micron-meter. In this report, the experimental investigations in the new feedback system are reported.

WEPME017	Development and Application of the Trigger Timing Watchdog System in KEK Electron/Positron Linac	linac, klystron, EPICS, electron	2962
	M. Satoh, K. Furukawa, F. Miyahara, T. Suwada KEK, Ibaraki, Japan T. Kudou, S. Kusano Mitsubishi Electric System & Service Co., Ltd, Tsukuba, Japan
	The KEK injector linac provides electrons and positrons to several accelerator facilities. A 50 Hz beam-mode switching system has been constructed to realize simultaneous top-up injections for Photon Factory and the KEKB high- and low-energy rings, which require different beam characteristics. An event-based timing and control system was built to change the parameters of various accelerator components within 20 ms. The components are spread over a 600-m-long linac and require changes to a total of 100 timing and control parameters. The system has been operated successfully since the autumn of 2008 and has been improved upon as beam operation experience has been accumulated. The timing watchdog and alert system are indispensable for the stable and high quality beam operation. For this purpose, we developed and utilized several timing watchdog system. We will present the detail of timing signal watchdog system for the KEK injector linac.

WEPME019	Development of Beam Position Feedback Control System in KU-FEL	FEL, feedback, gun, electron	2968
	H. Ohgaki, Y.W. Choi, H. Imon, T. Kii, R. Kinjo, T. Konstantin, K. Masuda, H. Negm, K. Okumura, M. Omer, S. Shibata, K. Shimahashi, K. Yoshida, H. Zen Kyoto University, Institute for Advanced Energy, Kyoto, Japan
	The stability of electron beam parameters such as position, energy etc. is very crucial for stable FEL operation. In Kyoto University MIR-FEL facility (KU-FEL), fluctuation of beam position and energy is caused by external fluctuations, such as the fluctuation in the cathode temperature of the thermionic RF-gun due to the back-streaming electrons, fluctuation of RF phase and amplitude, fluctuations of room and water temperatures, electric noises and so on. To monitor electron beam movement, we have already developed BPM system consisting of a 4-button electrode type BPM, a heterodyne detector, and CAMAC ADC in KU-FEL. By using this BPM system we have observed some correlations between external fluctuations and the beam position movements. In this conference, we will present the developed BPM system as well as the beam feedback system for stable KU-FEL operation.

WEPME022	Overview of the CSNS/RCS LLRF Control System	cavity, LLRF, feedback, beam-loading	2977
	X. Li, W. Long, H. Sun, C.L. Zhang, F.C. Zhao IHEP, Beijing, People's Republic of China
	The CSNS/RCS RF system consists of 8 ferrite-loaded RF cavities (h=2), each with individual digital LLRF control electronics. The injection and extraction energy of the beam are 80MeV and 1.6GeV respectively with a repetition rate of 25Hz. The RF system is designed to provide the maximum RF voltage of 165kV. The RF frequency range is from 1.02MHz at injection to 2.44MHz at extraction. The CSNS/RCS LLRF control system is based on FPGA, and composed of 7 control loops to achieve required acceleration voltage amplitude and phase regulation. A number of prototype and the first formal system have been completed and tested. In this paper we present an overview of the LLRF control system, and some operational results.

WEPME024	Gaussian Spectrum Fiber Laser Pulses Generated in an All-normal-dispersion Cavity	laser, cavity, background, status	2983
	Y. You, W.-H. Huang, C.-X. Tang, L.X. Yan TUB, Beijing, People's Republic of China H. Shimizu, J. Urakawa KEK, Ibaraki, Japan
	In this paper, we reported generating a broad bandwidth Gaussian shape spectrum fiber laser pulse directly in an all-normal dispersive cavity. Pulse-shaping is based on spectral filtering. The spectrum has a ~20 nm 20-dB spectrum bandwidth and it is different from the typical spectrum, of steep edge and two spikes. The Gaussian spectrum is preferred since it can be dechirped to transform-limited pulsed duration. The pulse duration corresponds to this kind of spectrum is ~315fs, and pulse energy is up to~9nJ, with a repetition rate of 18.9MHz.

WEPME025	The Surveying Data Processing of Control Network based on HLS Upgrade	survey, synchrotron, synchrotron-radiation, laser	2986
	W. Wang, X.Y. He, P. Wang, S.F. Xu, Q.Y. Yao USTC/NSRL, Hefei, Anhui, People's Republic of China
	The paper introduces the data processing procedure of control network based on the HLS upgrade. The Spatial Analyzer developed by New River Kinematics was used to adjust the data of surveying, In order to check the correctness of the adjustment result, The MAA developed by IHEP was also employed to make three-dimensional adjustment as well as plane adjustment done by SURVEY adding elevation adjustment by NASEW2003. Through comparing the results adjusted by different software, the SA is demonstrated reliable. At last, the cause why different software produces different results was analyzed depending on the adjustment principle of different software.

WEPME032	Development Status of SINAP Timing System	PLC, linac, status, background	2992
	M. Liu, D.K. Liu, C.X. Yin, L.Y. Zhao SINAP, Shanghai, People's Republic of China
	After successful implementation of SINAP timing solution at Pohang Light Source in 2011, the development of SINAP timing system version-II was finished by the end of 2012. The hardware of version-II is based on Virtex-6 FPGA chip, and bidirectional event frame transfer is realized in a 2.5Gbps fiber network. In event frame, data transfer functionality substitutes for distributed bus. The structure of timing system is also modified, where a new versatile EVO could be configured as EVG, FANOUT and EVR with optical outputs. Besides standard VME modules, we designed PLC-EVR as well, which is compatible with Yokogawa F3RP61 series. Based on brand new hardware architecture, the jitter performance of SINAP timing system version-II is improved remarkably.

WEPME033	Status of SSRF Fast Orbit Feedback System	feedback, EPICS, power-supply, synchrotron	2995
	C.X. Yin, B.C. Jiang, L.Y. Zhao SINAP, Shanghai, People's Republic of China
	As a 3rd generation light source, Shanghai Synchrotron Radiation Facility (SSRF) is pushing the requirement of beam stability to sub-micron in the range of DC to 100Hz. A fast orbit feedback system was designed and implemented to satisfy this requirement. In this paper, the layout of SSRF fast orbit feedback system, the structure of its electronics system and its hardware and software subsystems are described. The current status of SSRF fast orbit feedback system is presented.

WEPME034	Motion Control of the Mirror Chamber	EPICS, target, focusing	2998
	Z.H. Zhang, L.F. Zheng SSRF, Shanghai, People's Republic of China W.H. Jia, P. Liu SINAP, Shanghai, People's Republic of China
	Funding: Shanghai Institute of Applied Physics (SINAP), CAS, Shanghai 201800, P. R. China The initial beamlines of SSRF have several mirror chambers. The motion mechanism of the mirror chamber consists of six step motors. Three vertical motors are used to achieve the height translation, the roll adjustment and the pitch adjustment. Two horizontal motors are used to achieve the horizon translation and the yaw adjustment. The mirror bending is achieved by a single motor. Except the bending, every motion needs two or three motors to work simultaneously. The VME systems are used in the control system. The EPICS (Experimental Physics and Industrial Control System) toolkits [1] are adopted to develop the control software. This paper describes how to use motor records, transform records and the EPICS database linking mechanism to form soft loops, which solve the difficulties of the complex motions perfectly. The system has been successfully applied in the mirror chambers at SSRF.

WEPME036	The Development of LLRF System at PAL	LLRF, cavity, radio-frequency, monitoring	3004
	K.-H. Park, H.S. Han, Y.-G. Jung, D.E. Kim, H.-G. Lee, H.S. Suh PAL, Pohang, Kyungbuk, Republic of Korea J.-S. Chai, Y.S. Lee SKKU, Suwon, Republic of Korea B.-K. Kang POSTECH, Pohang, Kyungbuk, Republic of Korea
	The PAL has been developing the low level radio frequency (LLRF) system. The required field stabilities of the LLRF system are within ±0.75% in amplitude and 0.35° in phase in a cavity. All the hardware including RF front–end, FPGA with peripherals such as ADC, DAC, Oscillator and digital interface were assembled. The sub-modules for the RF signal processing were written by VHDL and integrated to test at the local facility. The macroblaze software processor was implemented to make the system simple in interfacing to peripherals and to secure flexibility later. This paper described the microblaze processor which was ported into the VERTEX6 FPGA. And also this paper showed the test results of the each module and integrated into the full system.

WEPME037	Fast Orbit Feedback at Taiwan Photon Source	brilliance, feedback, EPICS, storage-ring	3007
	A. Bardorfer, P. Leban I-Tech, Solkan, Slovenia P.C. Chiu, K.T. Hsu, C.H. Kuo NSRRC, Hsinchu, Taiwan
	Low latency, distributed, Fast Orbit Feedback (FOFB) application, based on singular value decomposition, entirely implemented in FPGA, has been developed for the Taiwan Photos Source (TPS). The FOFB utilizes the latest Libera Brilliance⁺ units for measuring beam position and the Gigabit Data eXchange (GDX) modules, which take care of global orbit distribution via 6.5 Gbit/s fiber optic or passive Cu links, and provide a large orbit data history buffer. The magnet correction in a matrix form of M = V . PI( S^-1 . U^T . ( Golden-Orbit ) ) is calculated entirely in FPGA, using a massively parallel approach and sent to the magnet power supplies via 2.5 Gbit/s link. The entire FOFB calculation is distributed over 48 GDX modules and the system allows for synchronous (on/off/pause) FOFB control via external input signal. The latencies of 60 ns per BPM for orbit distribution, 1.5 us for FOFB calculation and 1.5 us for magnet data transmission have been measured at TPS test installation in November 2012. The expected total communication and FOFB calculation latency in the TPS final configuration (168 BPMs) is expected to stay within 15-20 us range.

WEPME040	Investigation to Reduce Power Overhead Required in Superconducting RF Cavity Field Control	klystron, cavity, feedback, cathode	3013
	R. Zeng, S. Molloy, A. Sunesson ESS, Lund, Sweden A.J. Johansson Lund University, Lund, Sweden
	A power overhead of more than 25% is usually required in RF field control of klystron drived superconducting cavity, since it is much easier to implement feild control in a linear region of klystron where it is far below saturation. It however results in a reduced efficiency and more power consumption. Within ESS project it places very high demands on energy efficiency, which leads to stringent requirements on power overhead required in RF field control. Investigation on power overhead reduction in RF field control has been carried out at ESS and related simulation has been done. In this paper we will look at how close we can implement field control to the klystron saturation and discuss if it is possible to make RF field control the RF field with 10% overhead.

WEPME041	The Distance from CERN to LNGS	site, target, survey, alignment	3016
	M.A. Jones, I. Efthymiopoulos, D.P. Missiaen CERN, Geneva, Switzerland
	Obviously the distance between the CNGS Target at CERN and the LNGS Opera experiment cannot be measured directly and in fact requires the combination of three independent sets of measurements: two to link underground reference points at each site to corresponding points on the surface; and a third to link the surface points at both sites. Until the Opera results raised questions about the speed at which neutrinos travelled, the main alignment concern for the CNGS beamline had been an orientation problem -to ensure that the beamline arrived to within ~100 m of its target at LNGS. GPS measurements at the two sites, and the use of gyro-theodolite measurements in the tunnel at CERN, ensured that the absolute alignment of the beamline was established to the required accuracy. New determinations of the links between the surface and the tunnel were not considered necessary until interest grew in the distance between the sites, at which point additional measurement campaigns were organised in order to further reduce the uncertainty in the distance. Details of all these campaigns and the distance estimates will be given.

WEPME047	Identification of Sources of Orbital Distortions in Corrector Space	quadrupole, alignment, feedback, damping	3034
	M. Böge, M. Aiba, A. Saá Hernández, A. Streun PSI, Villigen PSI, Switzerland
	Since modern ring and linear accelerator based light sources feature fast orbit feedback (FOFB) systems which transform orbital oscillations in beam position monitor (BPM) space into corrector (C) space over a wide frequency range, most perturbations can be directly analyzed utilizing the C pattern. In C space the localization of sources of distortions is facilitated since the large (per unit phase) number of BPMs and Cs involved provides a good spatial resolution. Applications of this technique include the beam-assisted girder alignment where changes in the C pattern are interactively analyzed while girder positions are remotely altered or the beam-based alignment of quadrupole/BPM pairs where the variation of C values as the result of quadrupole variations are observed. In both cases large oscillations in BPM space are completely surpressed by the FOFB leading to well controlled and stable conditions during the measurement.

WEPME054	Girder Alignment in the Diamond Storage Ring	survey, alignment, storage-ring, quadrupole	3052
	M. Apollonio, R. Bartolini, W.J. Hoffman, A.J. Rose, A. Thomson Diamond, Oxfordshire, United Kingdom R. Bartolini JAI, Oxford, United Kingdom
	A model of the Diamond Storage Ring describing the misalignment of its 74 girders in terms of displacements and rotations is used to predict the orbit distortions and corrector magnet strengths needed for a zero orbit. Using the data from a survey we compare the effect of a pure magnet misalignment with the natural orbit of the machine. A test with a displaced girder meant to produce a reduction in corrector strength is introduced. Comparison with data obtained from the actual move of the girder is presented and discussed.

WEPME057	Commission of the Drive Laser System for Advanced Superconducting Test Accelerator	laser, gun, monitoring, cryomodule	3061
	J. Ruan, M.D. Church, D.R. Edstrom, Jr, T.R. Johnson, J.K. Santucci Fermilab, Batavia, USA

Paper

Title

Other Keywords

Page

MOPEA021

Status of the HESR Electron Cooler Test Set-up

electron, simulation, cathode, vacuum

115

M.W. Bruker, K. Aulenbacher, J. Dietrich, S. Friederich, A. Hofmann, T. Weilbach
HIM, Mainz, Germany
K. Aulenbacher
IKP, Mainz, Germany

For the proposed High Energy Storage Ring (HESR) at FAIR, it is foreseen to install an electron cooling device with a beam current of 3 A and a beam energy of 8 MeV. A test set-up was built at Helmholtz-Insitut Mainz (HIM) to conduct a feasibility study. One of the main goals of the test set-up is to evaluate the gun design proposed by TSL (Uppsala) with respect to vacuum handling, EM fields and the resulting beam parameters. Another purpose of the set-up is to achieve an energy recuperation efficiency of 1 - 10^-5. To measure this quantity, a Wien filter has to be employed, which will also prove capable of mitigating collection losses. The current status of the project will be presented.

MOPEA044

Maintenance Experience for Personnel Safety System at SSRF

PLC, radiation, synchrotron, synchrotron-radiation

175

J.J. Lu, P. Fei, G. Wang, X. Xia, J.Q. Xu, X.J. Xu
SINAP, Shanghai, People's Republic of China

To improve reliability and reduce faults of Personal Safety System (PSS) at Shanghai Synchrotron Radiation Facility (SSRF), two types of system maintenances were carried out since SSRF completion in 2009. The maintenances include maintenance during machine operation and that during shutdown period. The failures of the PSS are summarized for last 3 years operation, and the causes of these failures are analyzed. Main failures were occurred in the access control system and UPS power-supply mode during last 3 years operation. To treat these failures, detail maintenance plan and system upgrading schemes were carried out. After the maintenance and system upgrading, the numbers of beam shutdown which caused directly by the PSS failures are obviously reduced. It was 4 times beam shutdown in 2009 and 0 in 2011.

MOPEA053

Status of NSLS-II Booster

booster, dipole, vacuum, septum

196

S.M. Gurov, A.I. Erokhin, S.E. Karnaev, V.A. Kiselev, E.B. Levichev, A. Polyansky, A.M. Semenov, S.V. Shiyankov, S.V. Sinyatkin, V.V. Smaluk
BINP SB RAS, Novosibirsk, Russia
H.-C. Hseuh, T.V. Shaftan
BNL, Upton, Long Island, New York, USA

The National Synchrotron Light Source II is a third generation light source under construction at Brookhaven National Laboratory. The project includes a highly optimized 3 GeV electron storage ring, linac pre-injector and full-energy injector-synchrotron. Budker Institute of Nuclear Physics build booster for NSLS-II. The booster should accelerate the electron beam continuously and reliably from a minimum 170 MeV injection energy to a maximum energy of 3.15 GeV and average beam current of 20 mA. The booster shall be capable of multi-bunch and single bunch operation. Pre-comissioning test results of booster components and system are reviewed.

MOPEA054

A Review of 14 Years of Operation of Helios2 at SSLS

dipole, cryogenics, microtron, gun

199

Z.W. Li, M. Breese, E.P. Chew, C. Diao, M. Hua, A.W. Wong
SSLS, Singapore, Singapore

In this paper, we present the current status of the superconducting Helios2 Synchrotron and review its major problems and their solutions over the last 14 years. We described how various breakdowns in the cryogenics system, the control system, the RF system, Dipole power supplies, Ring gate valves and helium compressor have all been overcome and what valuable lessons have been learned in operating this machine.

MOPFI031

Progress on the Construction of the 100 MeV / 100 kW Electron Linac for the NSC KIPT Neutron Source

linac, electron, neutron, dipole

351

Y.L. Chi, J. Cao, P. Chen, B. Deng, C.D. Deng, D.Y. He, X. He, M. Hou, X.C. Kong, Q. Le, X.P. Li, J. Liu, R.L. Liu, W.B. Liu, H.Z. Ma, G. Pei, S. Pei, H. Song, L. Wang, S.H. Wang, X. Wang, Q. Yang, J. Yue, J.B. Zhao, J.X. Zhao, Z.S. Zhou
IHEP, Beijing, People's Republic of China
M.I. Ayzatskiy, I.M. Karnaukhov, V.A. Kushnir, V.V. Mytrochenko, A.Y. Zelinsky
NSC/KIPT, Kharkov, Ukraine
Y. Gohar
ANL, Argonne, USA

IHEP, China is constructing a 100 MeV / 100 kW electron linac for NSC KIPT, Ukraine. This linac will be used as the driver of a neutron source based on a subcritical assembly. In 2012, the injector part of the linac was pre-installed as a testing facility in the experimental hall #2 of IHEP. The injector beam and key hardware testing results were satisfying. Recently, the injector testing facility was disassembled and all of the components for the whole linac have been shipped to Ukraine from China by ocean shipping. The installation of the whole machine in KIPT will be started in June. The progress on the construction are reported, injector beam and key hardware testing results are presented.

MOPFI081

Correlating Structure and Function - In situ X-ray Analysis of High QE Alkali-antimonide Photocathodes

cathode, scattering, emittance, vacuum

464

J. Smedley, K. Attenkofer, S.G. Schubert
BNL, Upton, Long Island, New York, USA
I. Ben-Zvi, X. Liang, E.M. Muller, M. Ruiz-Osés
Stony Brook University, Stony Brook, USA
T. Forrest, H.A. Padmore, T. Vecchione, J.J. Wong
LBNL, Berkeley, California, USA
J. Xie
ANL, Argonne, USA

Funding: The authors wish to acknowledge the support of the US DOE, under Contract No. KC0407-ALSJNT-I0013, DE-AC02-98CH10886 and DE-SC0005713. Use of CHESS is supported by NSF award DMR-0936384.
Alkali antimonide photocathodes have high quantum efficiency and low emittance when illuminated by visible light, and are thought to be well suited for use in high-brightness photoinjectors of 4th generation light sources. Here we report on the growth of multi-alkali K2CsSb cathodes on [100] silicon substrates measured using in-situ X-ray diffraction (XRD) and X-ray reflection (XRR). Correlations between cathode structure and growth parameters and the resulting quantum efficiency (QE) are also explored. The best cathodes have a QE at 532 nm in excess of 6% and are structurally textured K2CsSb with grain sizes in excess of 20 nm. In an attempt to reduce the complexity of the current growth methodology we are also making alkali antimonides in parallel via the reaction of bulk materials in an inert environment. This approach has the advantage that the desired stoichiometry can be obtained exactly. Initial diffraction results from prepared bulk materials are promising and show the formation of well reacted K3Sb. In the future we intend to transfer this material to smooth thin photocathode films by either sputtering or pulsed laser deposition.

MOPME024

Status of Beam Loss Spatial Distribution Measurements at J-PARC Linac

proton, linac, status, klystron

524

H. Sako, T. Maruta, A. Miura
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

Funding: This work was supported by JSPS KAKENHI Grant Number 24510134.
We have developed 8-plane (4 horizontal and 4 vertical) scintillating fiber hodoscope system to measure proton tracks due to beam loss in the ACS section at the J-PARC linac. The detector consists of upstream 4 planes (two horizontal and two vertical) and downstream 4 planes (two horizontal and 4 vertical). The time of flight measuremments between the upstream and downstream subsystems allow proton identification and energy mesurements. In summer of 2012, we have installed remote position movement system, which enables measurements of spatial distributions of proton tracks. In this presentation we show status of mesurements and data analysis.

MOPME070

Emittance and Beta Functions Measurements for the MAX IV Linac

quadrupole, emittance, simulation, linac

640

N. Čutić, E. Mansten
MAX-lab, Lund, Sweden

We plan to determine beam emittance and Twiss parameters for the MAX IV linac using multiple-quadrupoles scans. We investigate the possibility to perform such scans using matching sections' quadrupoles combined with beam profile measurements by fluorescent YAG screens. Beam pipe size, resolution and screen saturation limits and strengths of quadrupoles are taken into consideration. Our approach to this problem using Kalman filter is presented.

MOPWA001

Development of a High Precision Integrator for Analog Signals to Measure Magnetic Fields in Realtime

pick-up, synchrotron, ion, feedback

661

E. Feldmeier, Th. Haberer
HIT, Heidelberg, Germany

For the Magnetic Field Control of the synchrotron at the Heidelberg Ion Therapy Centre the magnetic fields are measured with a pickup coil along the beam pipe. The induced pickup voltage, corresponding to changes in the magnetic field, has to be integrated in realtime to determine the actual field. A high precision integrator has been developed to measure fields with an accuracy of 4ppm over 10 seconds. This new integrator has a very low drift and calibrates during the measurement. It is the fastest and most accurate integrator for integrating analoge voltages in realtime.

MOPWA002

New Purposed High Precision Power Supply For Quadrupole Magnets Of ILSF using Low Resolution Digital PWM

power-supply, quadrupole, storage-ring, feedback

664

M. Jafarzadeh, M. Akbari, J. Rahighi, D. Shirangi, E.H. Yousefi
ILSF, Tehran, Iran

A total number of 10⁴ quadrupole magnets, split into 9 families, will be required for the ISLF storage ring lattice. Each quadrupole magnet is connected with its own independent power supply. In new design for quadrupole magnets, the outputs of two synchronized push-pull converters (one for coarse regulation and another for fine current regulation) will be added together before a synchronous rectification. In this manner, there will be no need for extra high-current electronic parts. Another advantage of this design is using a high-voltage inductor on the switching side rather than a high current inductor ion the high current side. The PWM signal to control of buck converter (at the input stage of each unit) will be generated inside a dsPIC .

MOPWA005

Development of a Feedback Control System for Resonant Power Supplies in the J-PARC 3-GeV Synchrotron

power-supply, feedback, impedance, quadrupole

672

Y. Watanabe
JAEA, Ibaraki-ken, Japan
N. Tani
JAEA/J-PARC, Tokai-mura, Japan

In the J-PARC 3-GeV Synchrotron, dipole magnets and seven families of quadrupole magnets are excited with a DC-biased 25 Hz sinusoidal waveforms using an individual resonant circuits. This paper proposed a feedback system to improve the amplitude and phase stability, specially against variation of capacitance caused by temperature characteristics in the resonant circuits. The control system has been successfully demonstrated and achieved amplitude and phase stability under ±0.005% and ±0.5 uS, respectively.

MOPWA006

Magnet Power Supply with Small Ripple using Sub-converter and Symmetrical Structure

power-supply, feedback, sextupole, extraction

675

S. Nakamura
J-PARC, KEK & JAEA, Ibaraki-ken, Japan
S. Yamada
KEK, Tokai, Ibaraki, Japan

High precision tracking and small current ripple are necessary for a magnet power supply of a high power accelerator. A prototype power supply of the 100kW class is developed with an aim of small current ripple less than 10ppm, which employs a combination of main and sub-converter with symmetrical structure. The main converter unit supplies pattern current by a voltage feedforward control, while the sub-converters by a current feedback control. The symmetrical structure of the power supply is adopted to decouple normal mode and common mode ripples. Each converter unit is modularized and surrounded by a Faraday cage suppress for suppressing radiation of electrical noise and ease for maintenance. Its performance is studied using a set of 24 units of setupole magnets installed in J-PARC Main Ring.

MOPWA008

Power Supply of the Pulse Steering Magnet for Changing the Painting Area between the MLF and the MR at J-PARC 3 GeV RCS

power-supply, injection, superconductivity, proton

681

T. Takayanagi, N. Hayashi, K. Horino, M. Kinsho, T. Togashi, T. Ueno, Y. Watanabe
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
Y. Irie
KEK, Ibaraki, Japan

The power supply of the pulse steering magnet (PSTR) has been produced. The PSTR of the 3-GeV RCS (Rapid Cycling Synchrotron) in the J-PARC (Japan Proton Accelerator Research Complex) aims at changing the painting area in a pulse-to-pulse mode at 25Hz between the MLF (Material and Life science Experimental Facility) and the MR (50-GeV Main Ring synchrotron) at J-PARC. The power supply has the equipment used to excite the pulse current and the direct current (DC) to correspond to two modes that the paint injection for beam users and the central injection for beam commissioning. In case of the paint injection, the power supply excites the current from 40 A to 450 A in pulse mode, which has the capability to switch from positive to negative polarity. The pulse current has been performed with good accuracy whose deviation to a setting current becomes to be less than ± 0.2 %. In case of the central injection, the power supply excites the current from 1000 A to 3000A in DC mode, which has been realized output current deviation below ± 0.01 %. This paper summarizes the design parameters and the experimental results of the power supply.

MOPWA013

The New Injection System of the HLS II

septum, kicker, pulsed-power, storage-ring

687

L. Shang, Y. Lu, F. Shang, Y.Y. Wang
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: The program is funded by NSFC with No. 10875116 and No. 11175181
The 0.8GeV storege ring is being rebuilt in NSRL. The design and construction of the new injection system of the new ring is presented. Kicker magnet, septum magnet and their pulsed power suplies are described. Test results are given. The ceramic chambers, vacuum tank of the septum magnet, system timing and local pulsed power control are also described. The installation and testing of the new system undergoing.

MOPWA014

Research and Design of Digital Power Supply for HIRFL-RIBLL Corrector Magnet

power-supply, feedback, secondary-beams, ion

690

Y.Z. Huang, Y.X. Chen, D.Q. Gao, J.B. Shangguan, R.K. Wang, H.H. Yan, Z.Z. Zhou
IMP, Lanzhou, People's Republic of China

One digital power supply was designed for RIBLL (Radioactive Ion Beam Line in Lanzhou) corrector magnet at HIRFL (Heavy Ion Research Facility in Lanzhou). Adopting two parallel connected IGBT full-bridges as the power circuit topology, the power supply can generate bipolar DC current when it runs in the fourquadrant working states, which well meets the requirements of corrector magnet. SOPC platform of Altera based on Nios II is chosen to design the digital power supply regulator. Employing FPGA as the control core and utilizing SOPC principles, the digital regulator is designed against special requirements of accelerator power supply. The test results indicate that performance of the power supply can meet the design requirements.

MOPWA015

The Control Strategy Research on Two Kinds of Topological Pulse Power Supply

power-supply, pulsed-power, heavy-ion, quadrupole

693

C.F. Shi, D.Q. Gao, Y.Z. Huang, H.H. Yan, Z.Z. Zhou
IMP, Lanzhou, People's Republic of China

This paper introduces a kind of pulsed power supply at HIRFL-CSR，analyzes the ripple and current error of the quadrupole magnet power supply in the operation process, and gives a two-stage topology of pulsed power supply. The control method is simulinked and the results show that the new one can make up for the deficiencies of the existing pulse power supply and the main circuit structure and control method are feasible.

MOPWA019

Digital Power Supply Controller Development Based on FPGA

power-supply, booster, synchrotron, synchrotron-radiation

702

R.N. Xu, C.L. Guo, D.M. Li, R. Li, S. Tan, W.F. Wu
SINAP, Shanghai, People's Republic of China

A digital power supply controller of SSRF (Shanghai Synchrotron Radiation Facility) adops advanced DSP, FPGA and precision ADC as core unit and data acquisition unit. The controller, which is embedded in the power supply case, is composed of two cards, DSP card and ADC card. The controller can communicate with IOC by optical fiber via the Ethernet, Manchester or RS-232 port. The parameters of adjusting power supply can be easily changed to achieve high stability and repeatability. The long-term stability is better than 20ppm. The resolution of current is better than 5ppm. As a replacement of imported PSI controller, the controller is mainly used in middle power supplies in SSRF, and it could accord with all the technical requirements of the facility.

MOPWA023

A Low Jitter Pulse Generator Based on Two-stage Storage Module

pulsed-power, coupling, simulation, high-voltage

711

J.N. Li, W.Q. Chen, F. Guo, W. Jia
NINT, Xi'an, People's Republic of China

A scheme for a low jitter pulse generator based on two-stage storage module is described. The thyristor is used for the first stage of the generator, the UV-illumination gas switch is used for the second stage of the generator. Between them, the pulsed transformer is used for connecting. A capacitance-resistance coupling structure was designed to produce UV light which triggered the switch to decrease the breakdown jitter. The test result shows, the risetime of the current is 0.73μs, the peak value of the current is 1.8kA on 1.1Ω load. The delay of the generator is 35.1μs, and the jitter of the generator attaches to 0.22μs.

MOPWA025

2Hz Ramping Mode Dipole Power Supply for Testing the NSLSII Booster Dipole Magnets

power-supply, dipole, booster, feedback

714

A.I. Erokhin, A.V. Bulatov, K. Gorchakov, S.M. Gurov, V.V. Kolmogorov, A.A. Kremnev, D.N. Pureskin, D.V. Senkov, R.V. Vakhrushev
BINP SB RAS, Novosibirsk, Russia

Budker Institute has designed and delivered Booster for NSLSII project including vacuum system, magnet system, diagnostics and power supplies. Dipole power supplies were directly delivered to BNL by sub-contractor (Danfysik, Denmark). To test dipole magnets on factory side, at BINP, it was decided to design and construct a high current ramping mode power supply. The designed power supply can operate with the reactive output power up to 150kVA and output current up to 900A at 2Hz ramping mode. The absolute accuracy achieved is better than 100ppm for the injection and extraction flats and better than 500ppm for the ramps.

MOPWA028

Power System for Quadrupole Magnets of NSLS-II 3 GeV Booster

quadrupole, booster, extraction, injection

723

D.V. Senkov, A.I. Erokhin, V.V. Kolmogorov, A.S. Medvedko, S.I. Potapov, D.N. Pureskin
BINP SB RAS, Novosibirsk, Russia

Power system for quadrupole magnets of NSLS-II 3 GeV booster is designed, manufactured and tested in BINP, Russia. The power system consists of 2 parts. The first part is a charging source with a capacitance bank at output. And the second part consists of 3 current sources powered by a capacitance bank. The charging source output voltage is up to 180 V, peak power is 40 kW and average power is 20 kW. Capacitance bank has a 120 kVA storage energy. The second part contains 3 independent current sources with up to 180 A output current each. This report considers the details of current sources design, their parameters and results of inspection test in BINP. Finally, the first results of injection and extraction section commissioning at BNL site are reported.

MOPWA029

Pulse Generators for Septums and Bumps of Injection and Extraction Systems of NSLS-II Booster

septum, injection, extraction, booster

726

D.V. Senkov, A.M. Batrakov, A.D. Chernyakin, V.A. Kiselev, A.V. Pavlenko, A.N. Zhuravlev
BINP SB RAS, Novosibirsk, Russia

Pulse generators for injection and extraction systems of NSLS-II 3 GeV booster are designed, manufactured and tested in BINP, Russia and installed and tested at BNL site. This report considers the details of bump, injection septum and extraction septum pulse generators design, their parameters and results of inspection test in BINP. The design and electronics features of control system of pulse generators are presented. Finally, the first results of injection and extraction section commissioning at BNL site are reported.

MOPWA040

Bipolar 10A and 50A Magnet Power Supplies for SwissFEL

power-supply, beam-losses, monitoring

756

R. Künzi, M. Emmenegger
PSI, Villigen PSI, Switzerland

15 years ago the Power Electronics Group at PSI, Switzerland developed power supplies (PS) for the magnets of the Swiss Light Source (SLS). These PS are based on switched mode converters with fully digital control. During the 12 years of operation of the SLS they have shown a very good reliability but also revealed some potential for improvement: After several years of operation the many fans installed started to fail more frequently and the same was observed for “off-the-shelf” AC/DC converters for the DC link. For the new SwissFEL, which shall be in service by 2016, approx. 610 PS rated at 10A and 40 PS rated at 50A will be necessary. As for any accelerator application high stability and reliability of the magnet PS are essential for high beam quality and availability. The development of the SwissFEL PS aims to raise the already good reliability by omitting as many fans as possible and adding redundancy for the AC/DC converters. Presently, a prototype rack with 21 10A PS is available and the mass production has started. The presented paper describes the PS concept and test results of the prototype regarding stability and efficiency are given.

MOPWA046

The Multi-channel Measuring Data Acquisition Interface for TPS Quadrupole and Sextupole Magnet Power Supplies by using LabVIEW as the Developing Tool

power-supply, quadrupole, sextupole, LabView

774

B.S. Wang, Y.-C. Chien, C.-Y. Liu, K.-B. Liu
NSRRC, Hsinchu, Taiwan
H.P. Tsai
Chroma ATE Inc., Taiwan

This paper presents an implementation of a multi-channel measuring data acquisition interface of quadrupole and sextupole magnet power supplies (MPS) for Taiwan Photon source (TPS) withLabVIEW as the developing tool. The multi-channel measuring data acquisition interface could reduce quantity of measurement instrument and loading of operator at the MPS acceptance test. The instrument devices of measurement system include a multiplexer 、 a dynamic signal analyzer (DSA) and a multi-channel digital voltage meter (DVM), GPIB is the communication protocol betweenthe multi-channel measuring data acquisition interfaceand instruments. There are threeanalyzing procedure for the output currentof MPSin the default setting of the LabVIEW program, 1) Fast Fourier Transform of output current measured by DSA, 2) long-term stability of output current measured by DVM, 3) the linear error function fitting of output current by LabVEW toolbox;after these three analyzing procedureis completed, the performance of each MPS can be automatically generatedas a Microsoft Word report file.

MOPWA047

Development of a Digital Control Interface Card with a LabVIEW Control Program for TLS Corrector Magnet Power Supply

LabView, feedback, power-supply, monitoring

777

B.S. Wang, K.-B. Liu
NSRRC, Hsinchu, Taiwan

This paper presents an implementation of a virtual instrument control interface and a digitally controlled interface card for Taiwan Light Source (TLS) corrector magnet power supplies (MPS). Eight pieces of corrector MPS converter module are monitored and controlled by the digitally controlled interface card with delimit boundary of ±10 voltage. The digitally controlled interface card was implemented with an ADS1278 24-bits multi-channel analog-to-digital converter、a DAC8718 16-bits multi-channel digital-to-analog converter and the TMS320F28335 digital signal processor. There are two control modes of the virtual instrument control interface, which are 1) local control mode by RS-232, 2) the remote control by MiiNePort\_E1 TCP/IP protocol; with the developed Labview control interface the user can choose which mode to communicate with the corrector magnet power supplies depending on the working environment.

MOPWA057

Development of a High-resolution, Broad-band, Stripline Beam Position Monitoring System

feedback, monitoring, linear-collider, extraction

804

G.B. Christian, D.R. Bett, N. Blaskovic Kraljevic, P. Burrows, M.R. Davis, Y.I. Kim, C. Perry
JAI, Oxford, United Kingdom
R. Apsimon, B. Constance
CERN, Geneva, Switzerland
P. Burrows, C. Perry
Oxford University, Physics Department, Oxford, Oxon, United Kingdom
J. Resta
IFIC, Valencia, Spain

A low-latency, sub-micron resolution stripline beam position monitoring system has been developed and tested with beam at the KEK Accelerator Test Facility, where it has been used as part of a feedback system for beam stabilisation. The fast analogue front-end signal processor is based on a single-stage down-mixer and is combined with an FPGA-based system for digitisation and feedback control. A resolution as low as 400 nm has been demonstrated for beam intensities of ~1 nC, with single-pass beam. The latest results of recent modifications to balance the input path lengths to the processor will be discussed. These modifications compensate for the inherent phase sensitivity of the processors, and hence improve the intrinsic resolution, without the need for offline correction. Modifications to the FPGA firmware will also be described, to allow for flexible operation with variable system-synchronous data acquisition at up to 400 MHz, with up to nine data channels of 13-bit width, and a nominal record length of 1 KS/channel/pulse (extensible to a total record length of 120 KS per pulse, for example, for use with long bunch trains or wide-band multi-turn measurements in storage rings).

MOPWA061

A New Tool for Longitudinal Tomography in Fermilab's Main Injector and Recycler Rings

booster, injection, emittance, space-charge

816

N.J. Evans, S.E. Kopp
The University of Texas at Austin, Austin, Texas, USA
P. Adamson, D.J. Scott
Fermilab, Batavia, USA

Funding: U.S Department of Energy
We are developing software to compute tomographic reconstructions of longitudinal phase space distributions in the Fermi National Accelerator Laboratory Main Injector and Recycler rings using data from existing resistive wall current monitors to diagnose beam quality at injection and provide input distributions for simulation of losses. Building on the algorithm developed by *S. Hancock et al. at CERN the software is able to process a full synchrotron period of a Booster batch of 81 bunches with 18.94 ns spacing and a sampling rate of 2.5 GHz, in < 30 sec, or every ~270 injections. Processing an entire injection opens up the possibility of investigating coupled bunch instabilities via tomography. To speed reconstruction for use on a full injection, phase space maps are created once for a given set of parameters and saved for injections with similar machine settings. We present an overview of the system and studies done on the effect of small errors present including: random noise, mismatch between sampling rate and machine period, errors in locating bunch centers, and trigger jitter.
*Tomographic Measurements of Longitudinal Phase Space Density; 1998 ed. - Hancock, S et al - CERN-PS-98-030-RF

MOPWA065

Affordable, Short Pulse MARX Modulator

high-voltage, shielding, linear-collider, collider

828

R.A. Phillips, M.P.J. Gaudreau, M.K. Kempkes, B.E. Simpson
Diversified Technologies, Inc., Bedford, Massachusetts, USA
J.A. Casey
Rockfield Research Inc., Las Vegas, Nevada, USA

Under a U.S. Department of Energy grant, Diversified Technologies, Inc. (DTI) is developing a short pulse, solid-state Marx modulator for the next generation of klystrons and accelerators. For short-pulse modulators, this Marx topology provides a means to achieve astounding risetimes and flattop control that are simply not available with hard switch or transformer coupled topologies. The design is a high peak-power pulse modulator of greater efficiency than presently available, in the 100 kV to 1 MV range, for currents of 0.1 to 1 kA, pulse lengths of 0.2 to 5.0 us, and rise/fall times 10% of pulse length. A key objective of the development effort is a design which is modular and scalable, yet low cost, and easy to manufacture and maintain. The modulator will be delivered to Yale Beam Physics Laboratory for evaluation, and will be affordable for deployment at other national labs for klystron and modulator evaluation. In this paper, DTI will describe the new design and provide an update on progress.

MOPWA066

Components of Heating and Fueling of Fusion Plasmas

high-voltage, simulation, cathode, synchrotron

831

K. Schrock, M.P.J. Gaudreau, M.K. Kempkes
Diversified Technologies, Inc., Bedford, Massachusetts, USA

Funding: Funded by US DOE, Grant # DE-SC0004250
Next generation fusion facilities will require many megawatts of RF power from dozens of gyrotrons. Each gyrotron requires a power system that must deliver the high-voltage power, modulate cathode voltage, and protect these expensive gyrotrons from arcing damage. It must be highly efficient, to minimize both the power and cooling costs associated with operation and to ensure high facility availability. Diversified Technologies, Inc. (DTI) has bench-tested a table-top scale ‘Buck Matrix’ modulator which uses a single set of IGBT switches for voltage regulation, arc protection, and pulse modulation. Although pulse step modulators represent a one-step solution, their size, and the complexity of their driving transformer make them more expensive than DTI’s two-step approach. DTI’s Buck Matrix modulator, with an efficiency of ~96%, cuts the size of the system in half, using a single layer of solid state switches for both voltage regulation and arc protection/modulation. This cuts the total hardware costs by a~30% or more, and eliminates the need for a separate opening switch or crowbar. DTI will present the system components of the design as well as the performance results to date.

MOPWA067

Robust High-average-power Modulator

klystron, neutron, power-supply, pick-up

834

I. Roth, N. Butler, M.P.J. Gaudreau, M.K. Kempkes
Diversified Technologies, Inc., Bedford, Massachusetts, USA

Funding: US DOE. Grant No. DE-SC0004254
Diversified Technologies Inc. (DTI) designed a modulator which meets the requirements of the Spallation Neutron Source (SNS) modulators at Oak Ridge National Laboratory and will be less expensive than copies of the current modulators. The SNS modulators, under development for a decade, still do not meet the specifications for voltage, droop, or pulsewidth. The modulators must provide pulses of 85 kV, 165 A, with pulsewidths of 1.5 ms and voltage flatness of 1%. The current modulator switches the full power at high frequency during each pulse, and has a complex output transformer. DTI designed a modulator that meets all specifications and is less expensive. The proposed design is cheaper because there is an HV switch that operates at full current only once per pulse, a corrector that switches only 5% of the power at high frequency, a low-cost transformer-rectifier power supply, and no output transformer. DTI’s patented switch uses IGBTs, allowing the switch to operate at full capacity even if 20% of the devices fail. The modulator will be installed in 2013 at SNS to test klystrons. DTI will present the system components of the design as well as the performance results to date.

MOPWA069

Time-resolved Electron Beam Position Monitor Macropulse Waveform Measurement in MkV Linear Accelerator at University of Hawaii Free Electron Laser Laboratory

electron, FEL, free-electron-laser, laser

837

P. Niknejadi, M.R. Hadmack, B.T. Jacobson, J. Madey, G.S. Varner
University of Hawaii, Honolulu, HI, USA

Real time waveform measurements of electron beams will provide valuable data and possibility of online bunch diagnostics in linear accelerators. The University of Hawaii Linear Accelerator utilizes a thermionic LaB6 cathode microwave gun injector and a single section of S-band linear accelerator capable of producing a 40MeV, 1-2 ps bunched electron beam with average current of 200mA over the duration of a 4.5 us macropulse. This beam, pulsed at 4 Hz, produces strong RF signal at 2.856 GHz which is coupled out of the beam-pipe by a family of stripline beam position monitors (BPM's) and read out using custom built logarithmic-difference based electronics installed in 2012.* A high speed Analog to Digital Convertor and Field-Programmable Gate Array will be used to digitize the signal and record the waveform. The goal is to make a cost effective oscilloscope on a chip/board with feasible and functional operation to achieve optimal beam configuration. The circuit board design, in-circuit programming, waveform digitization challenges, and preliminary results from the prototype will be presented at the conference.
* B. T. Jacobson, M. R. Hadmack, J. M. J. Madey, P. Niknejadi "Modular Logarithmic Amplifier Beam Position Monitor Readout System at University of Hawai’i," IBIC Conf. Proc. (2012)

MOPWA074

High Voltage Converter Modulator Optimization

high-voltage, neutron, feedback, background

852

A. Scheinker
LANL, Los Alamos, New Mexico, USA
M.J. Bland
University of Nottingham, Nottingham, United Kingdom

High voltage converter modulators (HVCM) are at the forefront of long pulse high voltage (100kV) technology for Klystron voltage sources. We present results of digitally implementing an extremum seeking (ES) algorithm with which we optimized the rise time of the output voltage of a HVCM at the Los Alamos Neutron Science Center (LANSCE) HVCM test stand by iteratively, simultaneously tuning the first 8 switching edges of each of the three phase drive waveforms (24 variables total). We achieved a 50us rise time, which is reduction in half compared to the 100us currently achieved at the Spallation Neutron Source (SNS) at Oak Ridge National Laboratory. The ES algorithm is successful despite the noisy measurements and cost calculations, confirming the theoretical predictions that the algorithm is not affected by noise unless it both matches exactly the frequency components of the controller's specific perturbing frequencies and is of comparable size.

MOPWA076

Improvements to Existing Jefferson Lab Wire Scanners

emittance, optics, diagnostics, linac

855

M.D. McCaughan, M.G. Tiefenback, D.L. Turner
JLAB, Newport News, Virginia, USA

This poster will detail the augmentation of selected existing CEBAF wire scanners with commercially available hardware, PMTs, and self created software in order to improve the scanners both in function and utility. Notice: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.

MOPWA077

EPICS, MATLAB, GigE CCD Camera Based Beam Imaging System for the IAC-RadiaBeam THz Project

EPICS, GUI, optics, background

858

C.F. Eckman, A. Andrews, T. Downer, Y. Kim, C. O'Neill
IAC, Pocatello, IDAHO, USA
P. Buaphad, Y. Kim
ISU, Pocatello, Idaho, USA
Y. Kim
JLAB, Newport News, Virginia, USA

At the Idaho Accelerator Center (IAC) of Idaho State University, we have been operating an L-band RF linear accelerator running at low energies (5 - 44 MeV) for the IAC-RadiaBeam THz project. We have designed and implemented an image acquisition and analysis system that can be used for real time observation of the electron beam, tuning of THz radiation production, and measurement of the transverse beam emittance. The imaging system contains an Yttrium Aluminium Garnet (YAG) screen on an actuator, a Prosilica GC1290 GigE CCD camera with an adjustable lens, a screen illuminator, an optical alignment structure, and a lead tube for the camera shielding. The real time continuous beam images can be acquired by SampleViewer, while the single shot beam image can be acquired by the Experiential Physics and Industrial Control System (EPICS) and areaDetector. In this paper, we describe components of the imaging system, the real time beam image acquisition with SampleViewer, the single shot beam image acquisition with areaDetector, and a remote controllable beam image acquisition via MATLAB Channel Access (MCA), MATLAB, and EPICS.

MOPWA087

Predictive Diagnostics for High-availability Accelerators

diagnostics, monitoring, klystron, extraction

873

K. Žagar, D. Bokal, K. Strniša
Cosylab, Ljubljana, Slovenia
M. Gašperin
University of West Bohemia, Pilsen, Czech Republic
L. Medeiros Romão, D. Vandeplassche
SCK•CEN, Mol, Belgium
G. Pajor
COBIK, Solkan, Slovenia

In Accelerator Driven Systems, high availability of the accelerator is one of its key requirements. Fortunately, not every beam trip is necessarily a failure. For example, in the proposed MYRRHA transmuter, absence of the beam for less than 3 seconds is still deemed acceptable. Predictive diagnostics strives to predict where a failure is likely to occur, so that a mitigating action can be taken in a more controlled manner, thus preventing failure of other components while exactly pinpointing the component that is about to fail. One approach to predictive diagnostics is to analyze process variables that quantify inputs and outputs of components as archived by the accelerator's distributed control system. By observing trends in their values an impending fault can be predicted. In addition, sensors measuring e.g., vibration, temperature or noise can be attached to critical components. By analyzing the signatures of signals acquired by these sensors, non-nominal behavior can be detected which possibly indicates a looming failure.

MOPWA088

FPGA Development Approach for Accelerator Systems with High Integration Complexity

neutron, alignment

876

J. Dedič, K. Žagar
COBIK, Solkan, Slovenia
A.M.M. Aulin Söderqvist, N.H. Claesson, R. Tavčar
Cosylab, Ljubljana, Slovenia
J. Neves Rodrigues
Lund University, Lund, Sweden

During the application-layer FPGA development for timing system for a medical accelerator (accelerator: MedAustron, timing system: Micro Research Finland) and a couple of other FPGA projects (power supply waveform generator, Machine Protection System proof of concept, ESS timing system demo) we got very good insight on how to approach demanding FPGA development that requires team work of many developers, coupled with particularities of accelerator system development. Because subsystems’ specific requirements evolve together with the operational understanding of the entire machine, the careful balance has to be taken between requirements gathering, prototyping and development stage. Furthermore, when doing architectural design decisions, knowledge from multiple domains should be taken into account; accelerator operation, software development and FPGA development. The design shouldn’t be register or counter centric, and FPGA functionality shouldn’t appear to the software developer as fixed – otherwise the design decisions of one world will sooner or later lead to spaghetti-code workarounds in the other world.

MOPWO018

Cellular Automaton Simulating the Motion of the Charged Particles Beam

acceleration, simulation, lattice

918

S.N. Andrianov, N.V. Kulabukhova
St. Petersburg State University, St. Petersburg, Russia
V. Ryabusha
Saint Petersburg State University, Saint Petersburg, Russia

In this research we formulate and formalize the rules for the cellular automaton that emulates the motion of the charged particles beam under the effect of Coulomb force for one-, two- and three-dimensional cases. In this research we also describe the main principles of the realization of this approach in a paralleled cluster environment.

MOPWO019

An IDE for Spin-orbit Dynamics Simulation

simulation, lattice, betatron, optics

921

A.N. Ivanov, N.V. Kulabukhova
St. Petersburg State University, St. Petersburg, Russia

In this paper a prototype of an IDE for simulation of spin-orbit motion is described. It is based on the component software development and provides a flexible graphic user interface. One of the main parts of it is numerical methods for ordinary differential equations integration. For numerical simulation it is possible use either the matrix map algorithm or traditional step-by-step methods. This workflow allows choosing one of numerical algorithms and to provide necessary computational experiments. It is also contains both a visual designer of an accelerator lattice and additional tools for control parameters of the model. There is also exists possibility for code generation in different programming languages and computation on high-performance systems.

MOPWO020

Space Charge Dominated Envelope Dynamics using GPUs

space-charge, simulation, luminosity, focusing

924

N.V. Kulabukhova
St. Petersburg State University, St. Petersburg, Russia

High power accelerator facilities lead to necessity to consider space charge forces. It is therefore important to study the space charge dynamics in the corresponding channels. To represent the space charge forces of the beam we have developed special software based on some analytical models for space charge distributions. Because calculations for space charge dynamics become extremely time consuming, we use a special algorithm for predictor-corrector method for evaluation scheme for beam map evaluation including the space charge forces. This method allows us to evaluate the map along the references trajectory and to create the beam envelope dynamics. The corresponding computer codes are realized using CUDA implementation of maps for particle dynamics. Some numerical results for different types of the beam channels are discussed. The survey of advantages and disadvantages of using different methods of parallelization and some parallel approaches will be done.

MOPWO032

SPS Scraping and LHC Transverse Tails

injection, emittance, beam-losses, luminosity

957

L.N. Drøsdal, K. Cornelis, B. Goddard, V. Kain, M. Meddahi, O. Mete, B. Salvachua, G. Valentino, E. Veyrunes
CERN, Geneva, Switzerland

All high-intensity LHC beams have to be scraped before extraction from the SPS to remove the non-Gaussian transverse tails of the particle distributions. The tail particles would otherwise cause unacceptably high losses during injection or other phases of the LHC cycle. Studies have been carried out to quantify the scraping using injection losses and emittance measurements from wire scanners as diagnostics. Beams scraped in the SPS were scraped again in the LHC with collimators to investigate possible tail repopulation. The results of these studies will be presented in this paper.

MOPWO040

Analysis of Failures of the LHC Collimators during the 2010-2013 Operation

collimation, injection, luminosity, insertion

981

S. Redaelli, A. Masi
CERN, Geneva, Switzerland

The LHC collimation system must be available in all phases of the machine operation in order to handle the high stored beam energies. The system availability is therefore crucial to achieve an efficient LHC operation. The collimation system has proved to work reliably in the first years of LHC operation, with total stored energies up to 140 MJ. The impact on the machine availability has been limited. The analysis of collimation system availability and the failure rate in the years 2012-2012 is reviewed with the aim to identify possible further improvements for the future.

MOPWO062

A Parallel Multi-objective Differential Evolution Algorithm for Photoinjector Beam Dynamics Optimization

emittance, electron, solenoid, gun

1031

J. Qiang, C.E. Mitchell, S. Paret, R.D. Ryne
LBNL, Berkeley, California, USA
Y.X. Chao
UCB, Berkeley, California, USA

Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231
In photoinjector design, there is growing interest in using multi-objective beam dynamics optimization to minimize the final transverse emittances and to maximize the final peak current of the beam. Most previous studies in this area were based on genetic algorithms. Recent progress in optimization suggests that the differential evolution algorithm could perform better in comparison to the genetic algorithm. In this paper, we propose a new parallel multi-objective optimizer based on the differential evolution algorithm for photoinjector beam dynamics optimization. We will discuss the numerical algorithm and some benchmark examples. This algorithm has the potential to significantly reduce the computation time required to reach the optimal Pareto solution.

MOPWO067

Beam Dynamics Simulations with a GPU-accelerated Version of Elegant

simulation, acceleration, collective-effects, storage-ring

1040

I.V. Pogorelov, K.M. Amyx, J. Balasalle, J.R. King
Tech-X, Boulder, Colorado, USA
M. Borland, R. Soliday
ANL, Argonne, USA

Funding: Work supported by the US DOE Office of Science, Office of Basic Energy Sciences under grant number DE-SC0004585, and by Tech-X Corporation
Large scale particle tracking and tracking-based lattice optimization simulations can derive significant benefit from efficient implementation of general-purpose particle tracking on GPUs. We present the latest results of our work on accelerating Argonne National Lab's accelerator simulation code ELEGANT*,** using CUDA-enabled GPUs. A sufficiently large number of Elegant beamline elements has been ported to GPUs to allow the GPU-accelerated simulation of realistic test lattices. We will identify some of performance-limiting factors, and briefly discuss optimization techniques for efficient utilization of the device memory space, with an emphasis on register usage. We also present a novel hardware-assisted technique for efficiently calculating a histogram from a large distribution of particle coordinates, and compare this to data-parallel implementations.
* M. Borland, Elegant: A Flexible SDDS-compliant Code for Accelerator Simulation, APS LS-287, September 2000
** Y. Wang, M. Borland, in Proc. of PAC07, THPAN095 (2007)

MOPWO086

Open XAL Status Report 2013

status, neutron, EPICS, target

1076

T.A. Pelaia
ORNL, Oak Ridge, Tennessee, USA

Funding: ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725
XAL is the well established, accelerator physics high level application programming framework developed for and used at the Spallation Neutron Source in Oak Ridge National Lab. Due to interest from other accelerator labs, the Open XAL project was formed in 2010 to port XAL to be more suitable for collaboration. The Open XAL architecture along with the objectives, status and roadmap of this effort are presented in this paper.

TUOCB202

Fast Orbit Feedback Scheme and Implementation for Taiwan Photon Source

feedback, power-supply, simulation, EPICS

1146

P.C. Chiu, K.T. Hsu, K.H. Hu, C.H. Kuo, C.Y. Wu
NSRRC, Hsinchu, Taiwan

TPS (Taiwan Photon Source) is a 3 GeV synchrotron light source which is being in construction at NSRRC. As most of 3rd generation light sources, the fast orbit feedback system would be adopted to eliminate various disturbances and improve orbit stability. Due to the vacuum chamber material made of aluminum with higher conductivity and lower bandwidth, both of slow and fast correctors will be used for FOFB correction. In general, there are two schemes to operate these hybrid correctors. One is to transfer correction from fast to slow correctors periodically and avoid fast corrector saturation. The other is the fast correctors operated only at higher frequency domain and slow ones take care of DC part. TPS would adopt the first scheme but the second one still as a substitute. Both schemes will be supported. This report summarizes the infrastructure of the FOFB and the simulation is also presented.

Slides TUOCB202 [3.035 MB]

TUODB201

Recent Progress on the Development of a High Gradient RF System using High Impedance Magnetic Alloy, FT3L

cavity, impedance, acceleration, synchrotron

1152

C. Ohmori, K. Hara, K. Hasegawa, M. Toda, M. Yoshii
KEK, Ibaraki, Japan
M. Nomura, A. Schnase, T. Shimada, F. Tamura, M. Yamamoto
JAEA/J-PARC, Tokai-mura, Japan

An upgrade project of J-PARC MR (Main Ring) includes developments of high gradient RF cavities and magnet power supplies for high repetition rate. A dedicated production system for high impedance magnetic alloy (FT3L) cores was assembled in J-PARC. This setup demonstrated that we can produce material with two times higher muQf product compared to the cores used for present cavities. And, the new results also show up to 20% higher impedance than the 2011 production with the former setup. In this summer, the system will be used for mass production of 200 FT3L cores for J-PARC MR. The cores produced in 2011 are already used for standard machine operation. The operation experience shows that the power loss in the cores was reduced significantly as expected. The scenario describing the upgrade plan of MR and the cavity replacements is reported. By the replacement plan, the total acceleration voltage will be almost doubled, while the number of RF stations remains the same.

Slides TUODB201 [5.105 MB]

TUPEA006

Towards Realistic Modelling of the FEL Radiation for the European XFEL

simulation, radiation, FEL, undulator

1173

I.V. Agapov, G. Geloni
XFEL. EU, Hamburg, Germany

For the operation phase of the European XFEL the possibility to characterize the FEL radiation taking realistic machine model into account is important. To achieve this, a software framework is being developed. It allows for interoperability of various simulation codes by means of a common graphical user interfaces, common input and output files, and common programming model for scripting; it includes the possibility of modeling beam jitters and machine imperfections to set errorbars on the simulation results, and has a connection to the control system for data acquisition. We report on the progress in the developing of this framework and give examples of FEL property calculations performed with it.

TUPEA038

Pre-chirp Control Broadband Non-collinear Optical Parametric Amplifier for the Future Laser Weak-field Accelerator

electron, laser

1223

L. Shen, C. Feng, L. Feng, D. Wang, H.F. Yao, W.Y. Zhang, Z.T. Zhao
SINAP, Shanghai, People's Republic of China

Ultra-short pulse has been proved to be a very useful tool for accelerating electron close to GeV now. But limited by gain narrowing effect, conventional CPA technology is quite hard to get less than 30fs at high energy level. Non-collinear optical parametric amplification (NOPA) looks more and more attractive for generating super-broadbandwidth pulses which is possible to be compressed to ultra-short pulses. Previous NOPAs, pumped by 400nm pulses, were using BBO crystals to reach shorter signal pulse durations. But the associated spectral bandwidths are still strongly linked with higher order nonlinear effects. which make it quite difficult to get higher energy with short pulse duration. Here we proposed to use pre-chirped few nm bandwidths around 515nm pumped pulses to amplify ultra-short pulses centered at 800nm. In our setup, we have found just one dramatical geometry configuration which support that we have possibility to get amplification from 720nm to 900nm, which will support to less than 10fs by well re-compression. This design is well adapted for BBO crystals. But the idea could be used also for other crystals.

TUPEA044

The Design of Control System for the Optical Cavity Adjuster of a FEL-THz Source

cavity, FEL, electron, undulator

1232

X. Liu, Q. Fu, B. Qin, P. Tan, C. Wang, Y.Q. Xiong, J. Yang, H. Zeng
HUST, Wuhan, People's Republic of China

The optical cavity adjuster is an important sub-system in a FEL-THz source, which is used to adjust the position and angle of the optical cavity with a high precision. In view of the requirements of the optical cavity adjuster of the FEL-THz source, this paper presents the design of the control system of the optical cavity adjuster. The design of the control system based on a PC and a motion controller is adopted. The motion controller controls high-precision linear stage to adjust linear direction and picomotors are controlled to enable the adjustment of roll and yaw. According to relevant calculation, the range of linear direction and the accuracy can be reached at ±3mm and 0.2~0.5μm; the range of the adjustment of roll and yaw and the accuracy can be reached at ±2° and 20″. In summing up it can be stated that the design meets the requirements and it also lays the foundation for engineering on developing the optical cavity adjuster.

TUPFI010

The LHCb Online Luminosity Control and Monitoring

luminosity, target, dipole, proton

1346

R. Alemany-Fernandez, F. Follin, R. Jacobsson
CERN, Geneva, Switzerland

The online luminosity control consists of an automatic slow real-time feedback system controlled by specific LHCb software, which communicates directly with a LHC software application. The LHC application drives a set of corrector magnets to adjust the transversal beam overlap at the LHCb interaction point in order to keep the instantaneous luminosity aligned to the target luminosity provided by the experiment. It was proposed and tested first in July 2010, and it has been in routine operation during the first two years of physics luminosity data taking, 2011 and 2012. This paper describes the operational performance of the LHCb experiment and the LHC accelerator during the luminosity control of the experiment, the accounting of the recorded luminosity and dead time of the detector, and analyses the beam stability during the adjustment of the transverse beam overlap at the interaction point.

TUPFI011

Study and Operational Implementation of a Tilted Crossing Angle in LHCb

dipole, luminosity, beam-losses, monitoring

1349

R. Alemany-Fernandez, F. Follin, B.J. Holzer, D. Jacquet, R. Versteegen, J. Wenninger
CERN, Geneva, Switzerland

The current crossing angle scheme at LHCb interaction point (horizontal crossing angle and vertical beam separation) prohibits the use of the LHCb dipole positive polarity for 25 ns bunch spacing operation since the beam separation at the first parasitic encounter is very small inducing unwanted beam encounters. To overcome this limitation a different crossing angle scheme was proposed in 2007 by W. Herr and Y. Papaphilippou. The new schema implies a vertical external crossing angle that together with the horizontal internal crossing angle, from the LHCb dipole and its three compensator magnets, defines a new tilted crossing and separation plane providing enough beam separation at the parasitic encounters. This paper summarizes the feasibility study of the new crossing scheme, the implementation in routine operation and analyzes the beam stability during the building up of the tilted crossing plane.

TUPFI013

LHC Long Shutdown: A Parenthesis for a Challenge

cryogenics, radiation, vacuum, superconducting-magnet

1355

K. Foraz, M. Arnaud, M.B.M. Barberan Marin, C. Bedel, M. Bernardini, J. Coupard, J. Etheridge, H. Gaillard, S. Grillot, E. Paulat, A.-L. Perrot
CERN, Geneva, Switzerland

After three fruitful years of operation, the LHC will enter a long shutdown. Major works will be implemented to allow running safely at 7TeV/beam. The LHC superconducting circuits will be consolidated; mitigation measures will be carried out to reduce the single event effects occurrence in the frame of the Radiation To Electronics mitigation project (R2E); all the equipment will be fully maintained. In parallel, numerous consolidation and upgrade activities will be performed all around the 27km ring. The schedule has been optimized in order to reduce the length of the shutdown (LS1) to 22 months (including hardware commissioning). The organization of the works is therefore essential to ensure a safe and reliable plan. This paper introduces the various activities to be performed and presents the schedule and the preparation process, including the operational safety aspects.

TUPFI033

Colliding During the Squeeze and β* Leveling in the LHC

luminosity, impedance, collider, optics

1415

X. Buffat
EPFL, Lausanne, Switzerland
W. Herr, M. Lamont, T. Pieloni, S. Redaelli, J. Wenninger
CERN, Geneva, Switzerland

While more challenging operationally, bringing the beams into collisions during the β squeeze rather than after presents some advantages. The large tune spread arising from the non-linearity of head-on beam-beam interactions can damp impedance-driven instabilities much more efficiently than external non-linearity such as octupoles presently used in operation. Moreover, colliding during the squeeze allows to level the luminosity, optimizing the pile-up in the experiments without changing the longitudinal distribution of collisions. Operational issues are discussed and experimental results from the LHC are presented.

TUPFI077

Commissioning Progress of the RHIC Electron Lenses

electron, solenoid, proton, lattice

1526

W. Fischer, Z. Altinbas, M. Anerella, M. Blaskiewicz, D. Bruno, W.C. Dawson, D.M. Gassner, X. Gu, R.C. Gupta, K. Hamdi, J. Hock, L.T. Hoff, R.L. Hulsart, A.K. Jain, P.N. Joshi, R.F. Lambiase, Y. Luo, M. Mapes, A. Marone, R.J. Michnoff, T.A. Miller, M.G. Minty, C. Montag, J.F. Muratore, S. Nemesure, D. Phillips, A.I. Pikin, S.R. Plate, P.J. Rosas, L. Snydstrup, Y. Tan, C. Theisen, P. Thieberger, J.E. Tuozzolo, P. Wanderer, S.M. White, W. Zhang
BNL, Upton, Long Island, New York, USA

Funding: Work supported by U.S. DOE under contract No DE-AC02-98CH10886 with the U.S. Department of Energy.
In polarized proton operation, the RHIC performance is limited by the head-on beam-beam effect. To overcome these limitations two electron lenses were installed and are under commissioning. One lens uses a newly manufactured superconducting solenoid, in the other lens the spare superconducting solenoid of the BNL Electron Beam Ion Source is installed to allow for propagation of the electron beam. (This spare magnet will be replaced by the same type of superconducting magnet that is also used in the other lens during the 2013 shut-down.) We give an overview of the commissioning configuration of both lenses, and report on first results in commissioning the hardware and electron beam. We also report on lattice modifications needed to adjust the phase advance between the beam-beam interactions and the electron lenses, as well as upgrades to the proton instrumentation for the commissioning.

TUPME001

Effect of Self-consistency on Space Charge Induced Beam Loss

resonance, simulation, space-charge, emittance

1556

G. Franchetti
GSI, Darmstadt, Germany

In long term storage space charge driven incoherent effect may lead to a slow beam diffusion that causes emittance growth and beam loss. However, when beam loss are relevant the full mechanism cannot be understood only driven by an incoherent effect. In this proceeding the issue of the self-consistency is discussed, and its impact presented for simplified examples and for the SIS100.

TUPWO019

A Local Achromatic Design of C-ADS MEBT2

emittance, linac, bunching, cavity

1922

H. Geng, Z. Guo, Z. Li, C. Meng, S. Pei, J.Y. Tang
IHEP, Beijing, People's Republic of China

The accelerator of China Accelerator Driven Sub-critical system consists of two injectors to ensure its high reliability. The Medium Energy Beam Transport line-2 is an essential part of the accelerator to transport and match the beam from either injector to the main linac. This paper presents a local achromatic design, which uses four bending magnets, for CADS MEBT2. It is found that both transverse and longitudinal emittance growths can be well controlled below 15% from MEBT2 entrance to the exit of the following superconducting spoke-021 section. The beam dynamics of MEBT2 will be discussed and the multi-particle tracking results will also be shown.

TUPWO040

Asymmetric Energy Colliding Ion Beams in the EDM Storage Ring

ion, storage-ring, proton, dipole

1961

I. Koop
BINP SB RAS, Novosibirsk, Russia

A possibility to bent equally two counter rotating ion beams by the crossed electric and magnetic fields is investigated. The first beam is polarized and its spin precession is adjusted to be synchronous with the velocity vector precession (a frozen spin method). The counter rotating unpolarized ion beam travels along the same orbit but with different velocity. Sensitive SQUID-type BPMs measure the vertical orbit difference of two beams. Later on this information is used to distinguish the EDM signal from the magnetic moment precession. Application of this approach to search of the EDM for proton, deuteron and helion is discussed.

TUPWO049

Automatic Correction of Betatron Coupling in the LHC using Injection Oscillations

coupling, injection, quadrupole, betatron

1979

T. Persson, T. Bach, D. Jacquet, V. Kain, Y.I. Levinsen, E.H. Maclean, M.J. McAteer, P.K. Skowroński, R. Tomás, G. Vanbavinckhove
CERN, Geneva, Switzerland
R. Miyamoto
ESS, Lund, Sweden

The control of the betatron coupling at injection and during the energy ramp is critical for the safe operation of the tune feedback and for the dynamic aperture. In the LHC every fill is preceded by the injection of a pilot bunch with low intensity. Using the injection oscillations from the pilot bunch we are able to measure the coupling at each individual BPM. The measurement is used to calculate a global coupling correction. The correction is based on the use of two orthogonal knobs which correct the real and imaginary part of the difference resonance term f1001, respectively. This method to correct the betatron coupling has been proven successful during the normal operation of the LHC. This paper presents the method used to calculate the corrections and its performance.

WEODB102

Generating Polarization Controllable FELs at Dalian Coherent Light Source

FEL, polarization, electron, undulator

2071

T. Zhang, H.X. Deng, D. Wang, Z.T. Zhao
SINAP, Shanghai, People's Republic of China
D.X. Dai, G.R. Wu, X.M. Yang, W.Q. Zhang
DICP, Dalian, People's Republic of China

Funding: 973 Program of China (2011CB808300), NSFC 11175240 and 11205234.
The property of the FEL polarization is of great importance to the user community. FEL pulses with ultra-high intensity and flexible polarization control ability will absolutely open up new scientific realms. In this paper, several polarization control approaches are presented to investigate the great potential on Dalian coherent light source, which is a government-approved novel FEL user facility with the capability of wavelength continuously tunable in the EUV regime of 50-150 nm. The numerical simulations show that both circularly polarized FELs with highly modulating frequency and 100 microjoule level pulse energy could be generated at Dalian coherent light source*.
*T. Zhang, et al., FEL Polarization Control Studies on Dalian Coherent Light Source, Chinese Physics C, 2013, to be published.

Slides WEODB102 [6.131 MB]

WEOBB202

Ultra-fast Data Acquisition System for Coherent Synchrotron Radiation Based on Superconducting Terahertz Detectors

synchrotron, radiation, electron, storage-ring

2094

C.M. Caselle, M. Hofherr, K.S. Ilin, V. Judin, A. Kopmann, A. Menshikov, A.-S. Müller, M. Siegel, N.J. Smale, P. Thoma, M. Weber, S. Wuensch
KIT, Eggenstein-Leopoldshafen, Germany
B.M. Balzer, S. Cilingaryan
Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen, Germany

The ANKA synchrotron radiation source located at the Karlsruhe Institute of Technology in Germany operates in the energy range between 0.5-2.5GeV and provides coherent synchrotron radiation. To resolve the ultra-short terahertz pulses emitted by a single bunch, thin YBCO superconducting film detectors have been developed. A response time of 45ps was determined as the FWHM at the output of the analog amplifier. A novel and high accuracy data acquisition architecture for sampling of the individual ultra-short terahertz pulses combined with real-time data processing based on GPUs for coherent synchrotron radiation is presented. The digitizer board is a made-in-house board designed for sampling of the fast pulse signals with pulse width between few tens of picosecond until 100ps. For each terahertz pulse five samples are acquired with a minimum sampling time of 3ps. A prototype setup with terahertz YBCO detectors, digitizer boards and the high-throughput FPGA framework has been successfully developed and tested at ANKA. The overview of the experimental setup including the YBCO detector technology and the preliminary results with single and multi-bunch filling pattern will be discussed.

Slides WEOBB202 [2.416 MB]

WEPWA026

Mechanical Design of Shift Driving System for DEPU at SSRF

polarization, simulation, undulator

2187

R.B. Deng, W.L. Chen, H.W. Du, Z.B. Yan, M. Zhang
SINAP, Shanghai, People's Republic of China

Double elliptically polarized undulator (DEPU) for a soft X-ray beamline for ARPES and PEEM is being built at SSRF. In DEPU, two EPUs with different period lengths have the roughly same magnet array lengths and share a common H style frame. The shift driving systems for polarization adjustment, which are set on top of the backing beams for the constraint of space, are sophisticated designed to assure position stability under longitudinal magnet force change. Finite-element analyses are also performed to guarantee the rigidity of the systems. The system performance is tested under full operation range and the results are described in this paper.

WEPWA028

Measurement and Research on Cryogenic Remanence of Chunks Permanent Magnet for Cryogenic Undulator

cryogenics, permanent-magnet, undulator, factory

2190

Y.Z. He
SINAP, Shanghai, People's Republic of China

The higher-precision cryogenic remanence measurment technology and error for chunks permanent magnet were researched in china firstly (10-300K). Magnetic measurement tooling and magnetic field calculation and measurement method of cryogenic remanence measurement system of chunks permanent magnet for cryogenic undulator were optimized. Cryogenic calibration Hall probe were pasted on surface of domestic chunks permanent magnet(Nd2Fe14B: N52, N50M, etc.) and table magnetic field B of permanent magnet were measured, and after being converted, then cryogenic remanence of domestic chunks permanent magnet were obtained and cryogenic remanence variation of domestic chunks permanent magnet were researched. Cryogenic remanence measurement data were checked by pulse B-H tester and PPMS respectively, the results show that cryogenic remanence data has higher reliability. By this experiment, initial foundation were established for development of SSRF cryogenic undulator and for cryogenic remanence measurement and study of domestic other chunks permanent magnets.

WEPWA029

Undulator Chamber R&D for SXFEL

undulator, vacuum, free-electron-laser, laser

2193

X. Hu, L. Yin
SINAP, Shanghai, People's Republic of China

The upcoming construction of Shanghai Soft X-ray Free Electron Laser Facility (SXFEL) will use 18 m small gap undulators. Each undulator is 3 meters long and will work at a minimum gap of 9 mm. This requires a vacuum chamber with an outer height of 8 mm and an elliptic inner aperture. The pressure inside of the chamber shall be less than 10^-5 Pa for the beam operation. An oxygen-free copper vacuum chamber was designed and a prototype was developed. This chamber includes three parts, a copper pipe manufactured by stretching, two flanges made of clad metal and a set of supports. The main fabrication procedure and the test results for the chamber prototype are described in this paper.

WEPWA032

The Feed-forward Control Design of Correction Coil Power Supply for SSRF EPU

EPICS, power-supply, undulator, insertion

2199

Q. Yuan, M. Gu, G.Y. Jiang, R. Wang
SINAP, Shanghai, People's Republic of China

The SSRF Elliptically Polarized Undulator (EPU) has been in operation for about three years. The feed-forward control algorithm of correction coil power supply (CCPS) is implemented in the Input and Output Controller (IOC) based on VME. The correction current responds not fast enough to gap movement, mainly because the communication between IOC and digital CCPS taking up much time. This paper introduces one new feed-forward design, that is ,on the one hand, the CCPS current responds to both gap movement and shift movement according to 2D Look-up Table(LUT) by linear interpolation method. On the other hand, feed-forward control algorithm is carried out in the EPU controller, and the CCPS with fast control response is directly controlled by PLC through analog interface. Thus, the correction current respond well to gap and shift movement owing to leaving out communication time.

WEPWA043

Construction of Injector Test Facility (ITF) for the PAL XFEL

gun, emittance, laser, klystron

2220

S.J. Park, H. J. Choi, T. Ha, J.H. Han, J.H. Hong, W.H. Hwang, H.-S. Kang, T.-H. Kang, D.T. Kim, J.M. Kim, S.-C. Kim, I.S. Ko, B.H. Lee, H.-S. Lee, W.W. Lee, C.-K. Min, Y.J. Park, Y.G. Son
PAL, Pohang, Kyungbuk, Republic of Korea
M.S. Chae
POSTECH, Pohang, Kyungbuk, Republic of Korea

Funding: Work supported by the Ministry of Education, Science and Technology (MEST) in Korea.
An injector test facility (ITF) for the PAL-XFEL has been successfully constructed and its commissioning is under way. The facility is to demonstrate beam performances required by the PAL XFEL (beam energy of 139 MeV, projected rms emittance of < 0.5 mm mrad @ 200 pC, and beam repetition rate of 60 Hz) with good enough stabilities. We have constructed a dedicated building for the facility in which a radiation-shielding tunnel (19.2-m long, 3.5-m wide, and 2.4-m high inner space), a klystron-modulator gallery, a laser room, and a control room are installed. The injector consists of an in-house-developed photo-cathode rf gun, a 30-mJ Ti:Sa laser system, two accelerating structures (as well as two sets of klystron-modulator systems), and various diagnostics as well as magnets & instrumentations. The installation of a transverse deflecting cavity (S-band, 10-fs resolution) and a laser heater is scheduled in 2013. In this article we report on the facility construction and some of the early commisisoning results.

WEPWA053

Control System of In-vacuum Undulator in Taiwan Photon Source

EPICS, vacuum, undulator, insertion

2238

C.Y. Wu, J. Chen, Y.-S. Cheng, P.C. Chiu, K.T. Hsu, C.Y. Liao
NSRRC, Hsinchu, Taiwan

Insertion device (ID) is a crucial component in third-generation synchrotron light sources, which can produces highly-brilliant, forward-directed and quasi-monochromatic radiation over a broad energy range for various experiments. In the phase I of the Taiwan Photon Source (TPS) project, seven IU22s (In-Vacuum Undulator) will be planned, constructed, and installed. The control system for IU22 is based on the EPICS architecture. The main control components include the motor with encoder for gap adjustment, trimming power supply for corrector magnets, ion pumpers and BA gauges for vacuum system, temperature sensors for ID environmental monitoring and baking, and interlock system (limit switches, emergency button) for safety. The progress of IU22 control system will be summarized in this report.

WEPWA054

Rejuvenation of Control System of the Undulator 50 in Taiwan Light Source

EPICS, undulator, insertion, insertion-device

2241

C.Y. Liao, J. Chen, P.C. Chiu, K.T. Hsu, C.Y. Wu
NSRRC, Hsinchu, Taiwan

The Undulator 50 (U50) for Taiwan Light Source (TLS) was installed on March 1997 at NSRRC. It provides service for more than 15 years. Control system of U50 includes a PC running MS-DOS for local control. Motion controller contains two indexers with driver via RS-232 interface. It equip with IEEE-488 interface to connect to the VME system for remote access. The response time for command and reply is in the order of second, thus the throughput of the experiment for energy scan is time-consuming. New U50 control system will share the standard environment for insertion devices (ID) control for the Taiwan Photon Source (TPS) project. Ethernet based motion controller was chosen to drive motor drivers. All control functionality will coordinate by the cPCI EPICS IOC. To compatible with TLS existed control environment, a server program was develop to translate the protocol to EPICS PVs. All existed GUI of TLS still can be used. These improvements of control system for U50 are essential upgrading geared to avoid obsolescence of the control related parts, increase productivity and support on-the-fly experiments. The progress of the controls plan will be summarized in this report.

WEPWA060

The Kharkov X-ray Generator Facility NESTOR

storage-ring, electron, lattice, injection

2253

A.A. Shcherbakov, V.P. Androsov, N. Ayzatsky, V.N. Boriskin, E.V. Bulyak, A.N. Dovbnya, P. Gladkikh, A.N. Gordienko, V.A. Grevtsev, A. Gvozd, V.E. Ivashchenko, A.A. Kalamayko, I.I. Karnaukhov, I.M. Karnaukhov, V.P. Kozin, V.A. Kushnir, V.P. Lyashchenko, V.S. Margin, N.I. Mocheshnikov, V.V. Mytrochenko, A. Mytsykov, I.M. Neklyudov, T.F. Nikitina, F.A. Peev, O.V. Ryezayev, V.L. Skirda, V.A. Skomorokhov, Y.N. Telegin, V.I. Trotsenko, A.Y. Zelinsky, O.D. Zvonarjova
NSC/KIPT, Kharkov, Ukraine
J.I.M. Botman
TUE, Eindhoven, The Netherlands
I.V. Drebot
LAL, Orsay, France

The last few years the sources of the X-rays NESTOR based on a storage ring with low beam energy and Compton scattering of intense laser beam are under design and development in NSC KIPT. The main task of the project is to develop compact intense X-ray generator on the base of relatively cheap accelerator equipment and up-to-date laser technologies. The paper is devoted to description of the last results on construction and commissioning of the facility.

WEPWO001

Power Couplers for XFEL

vacuum, site, pick-up, monitoring

2310

W. Kaabi, M. El Khaldi, A. Gallas, P. Lepercq, C. Magueur, A. Variola, A. Verguet
LAL, Orsay, France
W.-D. Möller
DESY, Hamburg, Germany

The LAL contribution to the XFEL project will be the delivery of 800 power couplers to equip 100 Cry-modules. The LAL’s tasks consist on the industrial monitoring and coupler quality control at two different production sites, in addition to the RF conditioning at LAL of the 800 produced couplers. The RF conditioning and all the coupler preparation process will be held in a 70m2 ISO5 clean room. An RF power station delivering 5MW, allow 8 couplers conditioning in the same time. Being in production control side and also RF conditioning one, the aim of LAL is to reach the rate of 8 couplers delivery per week, after a rump up phase. The starting of Coupler mass production is scheduled for beginning 2013.

WEPWO004

Studies of Systematic Flux Expulsion in Superconducting Niobium

niobium, cavity, simulation, lattice

2316

J.M. Vogt, J. Knobloch, O. Kugeler
HZB, Berlin, Germany

The quality factor Q0 that can be obtained in a superconducting cavity is known to depend on various factors like niobium material properties, treatment history and magnetic shielding. We believe that cooling conditions have an additional impact, as they appear to influence the amount of trapped flux and hence the residual resistance. We have constructed a test stand using niobium rods to study flux trapping. Here we can precisely control the temperature and approach Tc from below in the superconducting state. Although the sample remains in the superconducting state, a change in the amount of trapped flux is visible. The procedure can be applied repeatedly resulting in a significantly lowered level of trapped flux in the sample. Furthermore, simulations using the Radia software package for Mathematica developed by the ESR were used to better unterstand the measured changes in magnetic flux around the Sample. Applying a similar procedure for minimization of trapped magnetic flux to a superconducting cavity could allow for reduction of the magnetic contribution to the surface resistance and result in a significant improvement of Q0.

WEPWO011

In-vacuum Temperature Measurement of Niobium Components using Infrared Pyrometry during Electron Beam Welding Procedure

cavity, vacuum, electron, shielding

2334

L. Monaco, P. Michelato, C. Pagani, D. Sertore
INFN/LASA, Segrate (MI), Italy
V. Battista, G. Corniani, M. Festa
Ettore Zanon S.p.A., Schio, Italy

Electron beam welding (EBW) is widely used in the construction of Niobium Superconducting RF cavities. The welding sequence of such a complex structure, foresees many welding operations. The welding parameters depend on many variables as the material thickness, but also on the component temperature before each weld. This paper presents a technique to measure the temperature of Nb components in vacuum during the EBW operation using an IR pyrometer placed outside the vacuum chamber through an appropriate vacuum viewport. With the current configuration the system can measure temperatures up to 350°C in the vacuum conditions of the EBW vacuum chamber (10-5-10^-6 mbar). The technique was used to optimize the time interval between each subsequent equatorial weld operation during Nb cavities production at Ettore Zanon, increasing the welding procedure reliability and decreasing the waiting time by control of the temperatures in the weld region. Moreover this technique can be generally used for in vacuum measurements of components from room temperature up to about 350 °C. Future developments are under way to make this technique compatible with UHV and increasing the measurement range.

WEPWO019

Development of Frequency Measurement Setup for ADS 650MHz and 1.3GHz Superconducting RF Cavities at IHEP

cavity, SRF, linac, simulation

2358

S. Jin, J. Gao, Y. Liu, Z.C. Liu, J.Y. Zhai, T.X. Zhao, H.J. Zheng
IHEP, Beijing, People's Republic of China

The Accelerator Driven Sub-critical System (ADS) is under development in China, and the 650MHz β=0.82 superconducting RF cavity (SRF) has been chosen as a possible candidate to accelerate the proton bunches in the medium energy section from 360MeV to 1.5GeV [1]. In order to obtain quality management and quality assurance during fabrication, radio frequency measurements on parts and subassemblies of SRF cavities become a proper method [2]. In this paper, study on developing a new frequency measurement setup mainly for half cells, dumb-bells and end groups of ADS650MHz cavities at IHEP was reported. A digital pressure sense was assembled in the setup. Together with the simulation on the structural and frequency by ANSYS Workbench, a quantitative standard for the frequency measurement was built for the cavity fabrication. Since a 9-cell TESLA-Like cavity is also under study in the meantime, via a slight modification, the setup can be also used for it.

WEPWO025

Preliminary Design of 325 MHz Half-Wave Resonator

cavity, simulation, proton, heavy-ion

2369

X.Y. Zhang, X. Chen, Z.Q. Li, Q. Ma, W.M. Pan, Y. Sun, G.W. Wang, Q.Y. Wang, B. Xu, G.Y. Zhao
IHEP, Beijing, People's Republic of China

Funding: This work is supported by the "Strategic Priority Research Program" of CAS.
The Half-Wave Resonator (HWR) has been widely used in proton and heavy ion accelerators, for it has particular advantages of accelerating low energy charged particles. Preliminary design of a 325 MHz β=0.12 superconducting HWR cavity has been proposed at Institute of High Energy Physics (IHEP). The basic geometric parameters choices of the cavity are based upon theoretical model and numerical calculation, and then the RF performances are optimized by extensive electromagnetic simulations. In this paper, the detailed mechanical analysis, frequency control, and the considerations for fabrication of the 325 MHz HWR cavity are also presented.

WEPWO036

Conceptual Design of a Superfluid Superconducting Third Harmonic RF System for the SSRF Storage Ring

cavity, superconducting-cavity, cryogenics, synchrotron

2381

H.T. Hou, J.F. Liu, Z.T. Zhao
SINAP, Shanghai, People's Republic of China
J.F. Liu
Shanghai KEY Laboratory of Cryogenics & Superconducting RF Technology, Shanghai, People's Republic of China

Harmonic cavity can improve the beam quality through bunch size lengthening which includes providing Landau damping, suppressing coupled bunch instability and microwave instability, enhancing the beam current per bunch besides the beam lifetime improvement. A passive third harmonic superconducting cavity operating at super fluid liquid helium has been proposed for the SSRF storage ring with compromise on the required harmonic voltage, limited installation space and dissipated cryogenic power. This paper will mainly present the conceptual design of the harmonic rf system including the requirement of SSRF, a brief review on beam dynamics of harmonic rf system and the harmonic cavity choice.

WEPWO043

IFMIF-EVEDA SRF Linac Couplers Test Bench

vacuum, linac, SRF, LLRF

2396

D. Regidor, I. Kirpitchev, J. Molla, P. Méndez, A. Salom, M. Weber
CIEMAT, Madrid, Spain
M. Desmons, N. Grouas, P. Hardy, V.M. Hennion, H. Jenhani, F. Orsini
CEA/IRFU, Gif-sur-Yvette, France

The IFMIF-EVEDA SRF Linac is a cryomodule equipped with eight superconducting HWR cavities, operating at the frequency of 175 MHz and powered by 200kW CW RF couplers. Before assembling the couplers to the cryomodule, it is necessary to process them using high levels of RF power. In order to perform this conditioning, the power couplers must be connected to a RF network which is fed by an RF source and ended with a load or a short-circuit, depending on the conditioning mode to be applied. A test bench has been designed for the conditioning of the SRF LINAC couplers. The main component is the “test box”, a resonant cavity where two couplers will be assembled to transmit the 200 kW from the RF source to the appropriate termination. The test box includes a large pumping port allowing an efficient pumping of the entire vacuum volume limited by the coupler ceramic windows. Several diagnostics as light detectors, vacuum gauges and thermal transducers will provide information on the relevant parameters for the control of the RF conditioning process. In addition, a support frame has been designed to maintain the whole assembly and reduce the mechanical stress on the couplers.

WEPWO058

Recent Progress at Fermilab Controlling Lorentz Force Detuning and Microphonics in Superconducting Cavities

cavity, resonance, cryomodule, SRF

2438

W. Schappert, Y.M. Pischalnikov
Fermilab, Batavia, USA

Funding: Work is supported by U.S. Department of Energy
SRF cavities are susceptible to detuning by mechanical deformations induced by the Lorentz force and microphonics. Providing the RF overhead required to maintain the accelerating gradient in detuned cavities can increase both the capital and operating costs of superconducting accelerators. Recent work at Fermilab has shown that active vibration control using a piezo actuator can reduce both Lorentz Force detuning and microphonics to the point where negligible RF overhead is required to maintain the accelerating gradient.

WEPWO066

Frequency Control in the Cornell-ERL Main-Linac Cavity Production

cavity, niobium, target, LabView

2453

V.D. Shemelin, B. Bullock, P.R. Carriere, B. Clasby, R. Eichhorn, B. Elmore, J.J. Kaufman, J. Sears
CLASSE, Ithaca, New York, USA

Funding: NSF award DMR-0807731
Cavity fabrication can be broken down into three main stages: deep-drawing cups, welding the cups in pairs to obtain “dumbbells” and end groups, and, finally, welding the obtained components into a completed cavity. Frequency measurements and precise machining were implemented after the second stage. A custom RF fixture and data acquisition system were used for this purpose. The system comprised of a mechanical press with RF contacts, a network analyzer, a load cell and custom LabVIEW and MATLAB scripts. To extract the individual frequencies of the cups from these measurements, algorithm of calculations was developed. Corrections for the ambient environment were also incorporated into the measurement protocol. Two 7-cell 1.3 GHz cavities were produced with high field flatness immediately after fabrication.

WEPWO082

Ferroelectric Based High Power Tuner for L-band Accelerator Applications

linac, cavity, vacuum, simulation

2486

A. Kanareykin
Euclid TechLabs, LLC, Solon, Ohio, USA
S. Kazakov, V.P. Yakovlev
Fermilab, Batavia, USA
A.B. Kozyrev
LETI, Saint-Petersburg, Russia
E. Nenasheva
Ceramics Ltd., St. Petersburg, Russia

Funding: US Department of Energy
With this paper, we present our recent breakthrough with a new fast ferroelectric tuner development. The tuner is based on BST(M) ferroelectric elements (ε~150), which are designed to be used as the basis for L-band accelerator components intended for ERL, ILC, Project X and other applications. These new ferroelectric elements are to be fabricated for the new fast active tuner for SC cavities that can operate in air at low biasing DC fields. Note there were no reliable results on the long-term piezo actuators operations in CW regime. Specific features of ERL, ILC and Project X accelerator technology and challenges of the designs are high magnitude and phase stability of its operations. Mechanical vibrations, or microphonics affect the SRF resonator, while the ferroelectric tuners have shown extremely high tuning speed. We have demonstrated successful mitigation of the residual effects on the ferroelectric-metal interface along with the acceptable level of the overall loss factor of the tuner element. A new concepts of a tuning element based on low dielectric constant ferroelectrics along with fabrication technology of these new BST(M) ferroelectric elements will be presented.

WEPEA010

Modeling Longitudinal Bunched Beam Dynamics in Hadron Synchrotrons using Scaled Fourier-Hermite Expansions

synchrotron, simulation, hadron, feedback

2513

K. Gross, D.E.M. Lens
TU Darmstadt, RTR, Darmstadt, Germany

To devise control strategies and to analyze the stability of systems with feedback, a set of few ODEs describing the underlying dynamics is required. Numerical Fourier-Hermite solutions of the Vlasov equation have been studied for over fifty years. The idea to expand the distribution function in Fourier series in space and Hermite functions in velocity is transferred to the dynamics of bunched beams in hadron synchrotrons in this contribution. The Hermite basis is a natural choice for plasmas with Maxwellian velocity profile as well as for particle beams with Gaussian momentum spread. The Fourier basis used for spatially nearly uniform plasmas has to be adapted to bunched beams where the beam profile is not uniform in phase. This is achieved analogously to the deduction of the three term recursion relations to construct orthogonal polynomials, but applied to Fourier series with the weight function taken from the Hamiltonian. The resulting system of ODEs for the expansion coefficients of desired order - dependent on the number of functions retained - is checked against macro particle tracking simulations.

WEPEA038

Two and three Dimensional Models for Analytical and Numerical Space Charge Simulation

space-charge, linac, simulation, ion

2585

S.N. Andrianov, N.V. Kulabukhova
St. Petersburg State University, St. Petersburg, Russia

In this article there is described an analytical approach to describe the self-field of two- and three dimensional ellipsoidal presentation of space charge distribution. The corresponding results can be evaluated in both numerical and the analytic presentation for some model distributions of charge. The corresponding results can be embedded in the Lie formalism used to describe the map for the beam dynamics. The corresponding linear and nonlinear maps are evaluated in terms of the matrix representation of the evolution operator of the beam. Appropriate solutions for nonlinear differential equations are based on a prediction-correction method (the converging recursive procedure). These solutions are compared with the Vlasov equation solutions. A special software package for the described approach is presented.

WEPEA041

Actions To Mitigate The Radiation Damage to Electronics at the LHC

shielding, radiation, hadron, civil-engineering

2591

A.-L. Perrot, M.B.M. Barberan Marin, J.-P. Corso, K. Foraz, M. Lazzaroni, Y. Muttoni
CERN, Geneva, Switzerland

The level of flux of hadrons with energy in the multi MeV range expected from the collisions at the LHC interaction Points 1, 5 and 8 and from the collimation system at Point 7 will induce Single Event Errors (SEEs) in the standard electronics present in many of the control equipment installed in LHC underground. Furthermore, a risk of SEEs induced by thermal neutrons cannot be excluded. Such events would perturb the LHC operation, possibly leading to a stop of the machine. Main mitigation actions will be implemented during the first LHC Long Shutdown of 2013/2014 (LS1) to reduce the SEE occurrence. This paper summarizes the mitigation measures and their associated foreseen improvements in terms of SEEs. It presents the organization process and associated planning highlighting the impacts with the overall LHC LS1 planning and the main concerns during implementation.

WEPEA043

Working Point and Resonance Studies at the CERN PS

resonance, injection, octupole, focusing

2597

A. Huschauer, M. Benedikt, H. Damerau, P. Freyermuth, S.S. Gilardoni, R. Steerenberg, B. Vandorpe
CERN, Geneva, Switzerland

The increase of luminosity demanded by the High Luminosity LHC (HL-LHC) requires an increase of beam intensity, which might result in instabilities appearing at injection energy in the CERN PS. Transverse head-tail instabilities have already been observed on operational LHC beams and a stabilizing mechanism as an alternative to linear coupling is currently being studied. It consists of reducing the mode number of the transverse oscillation by changing linear chromaticity and in succession completely suppressing the instability by a transverse damper system with appropriate bandwidth. Therefore, a chromaticity correction scheme at low energy exploiting the intrinsic possibilities offered by special circuits mounted on top of the main magnet poles, the Pole Face Windings (PFW), has been examined. The presence of destructive betatron resonances, which restrict the choice of the injection working point and the maximum acceptable tune spread, forms an additional limitation for high-brightness and high-intensity beams in the CERN PS. To improve the current working point control scheme, the influence of the P F W on the machine resonances is presented in this paper.

WEPEA044

RF Manipulations for Higher Brightness LHC-type Beams

injection, brightness, emittance, extraction

2600

H. Damerau, A. Findlay, S.S. Gilardoni, S. Hancock
CERN, Geneva, Switzerland

In order to increase the transverse brightness of beams for the LHC, ever more complicated RF manipulations have been proposed in the PS machine in order to reduce the intensity demands per PS batch on the upstream PS Booster. Several schemes based on cascades of batch compression, bunch merging, as well as the more routine bunch splitting have been successfully commissioned and higher brightness beams have been delivered to the downstream accelerators for measurement. Despite all this complexity, longitudinal and transverse beam quality are well preserved. In addition, to fully profit from the brightness of all four PS Booster rings, the injection of twice 4 bunches into harmonic 9 buckets in the PS has been made operational as an alternative to the usual double-batch transfer of 4+2 bunches into harmonic 7. This paper summarizes the new beam production schemes, their implementation in the PS low-level RF system and the experimental results.

WEPEA055

Quantitative Evaluation of Trapping and Overall Efficiency for Simple Models in One-degree of Freedom

resonance, simulation, synchrotron, extraction

2630

C. Hernalsteens, C. Frye, M. Giovannozzi
CERN, Geneva, Switzerland
A. Bazzani
Bologna University, Bologna, Italy

A key ingredient for the Multi-Turn Extraction at the CERN Proton Synchrotron is the beam trapping in stable islands of transverse phase space. The control of the trapping process is essential for the quality of the final beam in terms of intensity sharing and emittance. In this paper, a method allowing an analytical estimation of the fraction of beam trapped into stable islands as a function of the Hamiltonian parameters is presented for a very simple model of the dynamics (pendulum) and is extended to the case of the interpolating Hamiltonian of the Hénon model, the latter being a good 2D model of the MTE dynamics. The analytical results are compared with numerical simulations. Additional numerical simulations are presented for the minimum trapping amplitude and a fitted model is proposed. Results are discussed in detail.

WEPEA063

Upgrades and Consolidation of the CERN AD for Operation during the Next Decades

target, antiproton, electron, vacuum

2654

T. Eriksson, M. E. Angoletta, L. Arnaudon, J.A. Baillie, M. Calviani, F. Caspers, L.V. Joergensen, R. Kersevan, G. Le Godec, R. Louwerse, M. Ludwig, S. Maury, A. Newborough, C. Oliveira, G. Tranquille
CERN, Geneva, Switzerland

As the ELENA project is now well underway, focus is turned to the Antiproton Decelerator (AD) itself. Most of the machine’s key components are in operation since more than 25 years and a substantial consolidation program is now being launched in view of continued operation beyond 2025. Over the course of the next few years a progressive consolidation of the AD-Target area, the AD-ring and all associated systems will take place. Several investigations have recently been performed in the target area with the objective of establishing the radiation environment and the sensitivity of the antiproton production to potential misalignment of the production elements. Identification of reliability and serviceability issues of the AD-ring components and associated systems has been done and will continue during the 2013 shut-down. Planned and ongoing consolidation activities are also discussed with emphasis on stochastic and electron beam cooling, instrumentation, RF systems, vacuum, magnets, power converters and beam transfer equipment.

WEPEA065

Beam Tests and Plans for the CERN PS Booster Wideband RF System Prototype

cavity, feedback, LLRF, booster

2660

M.M. Paoluzzi, M. E. Angoletta, A. Findlay, M. Haase, M. Jaussi
CERN, Geneva, Switzerland

In the framework of the LHC Injectors Upgrade project (LIU) and in view of a complete replacement of the existing CERN PS Booster (PSB) RF systems, a prototype cavity has been installed beginning of 2012 in the machine. This modular, wideband (0.5 / 4 MHz), Finemet® loaded system uses solid-state power stages and includes fast RF feedback for beam loading compensation. In depth studies have been performed during 2012 to evaluate the system interaction with the new low-level digital electronics, its ability to accelerate the beam and cope with high beam intensity. The encouraging results suggest that this innovative approach can indeed be used to replace all the existing PSB RF systems but additional testing with a full scale prototype is required. This paper reports about the project status, the achieved results, the encountered difficulties and the foreseen prototype completion in preparation during 2013.

WEPEA069

Review of the Drive Beam Stabilization in the CLIC Test Facility CTF3

feedback, linac, klystron, low-level-rf

2666

A. Dubrovskiy, L. Malina, P.K. Skowroński, F. Tecker
CERN, Geneva, Switzerland
T. Persson
Chalmers University of Technology, Chalmers Tekniska Högskola, Gothenburg, Sweden

CTF3 is a Test Facility focusing on beam-based studies of the key concepts of the Compact Linear Collider CLIC. Over the past several years many aspects the CLIC two-beam acceleration scheme were studied in CTF3, including the crucial issue of drive beam stability. The main sources of drifts and instabilities have been identified and mitigated, helping to improve the machine performance and showing significant progress towards the experimental demonstration of the very stringent requirements on current, energy and phase stability needed in CLIC. In this paper, the more effective techniques and feed-backs are summarized. The latest measurements on beam stability are reported and their relevance to CLIC is discussed.

WEPFI002

Acceptance Tests for the Spiral2 SC Linac RF Power Systems

cavity, linac, impedance, insertion

2702

M. Di Giacomo
GANIL, Caen, France

Funding: This activity received founds from the EuCard RF Tech program
The Spiral2 SC linac uses solid state amplifiers ranging from 2,5 to 19 kW and external circulators to drive normal and superconducting cavities at 88.0525 MHz. The project has no manpower for in house development and all power devices are ordered to commercial companies. Robust acceptance tests have therefore been defined to check reliability with respect to our application. The papers describes the tests procedure and results on our first units.

WEPFI005

Simulations and RF Measurements of the Fundamental and Higher Order Modes of the ThomX 500 MHz Cavity

cavity, HOM, impedance, feedback

2711

M. El Khaldi, I.V. Drebot, P. Lepercq, R. Marie, B. Mercier, T. Roulet, A. Variola, F. Wicek
LAL, Orsay, France
H.D. Dias, M.D. Diop, M.E. El Ajjouri, R. Lopes, A. Loulergue, P. Marchand, F. Ribeiro, R. Sreedharan
SOLEIL, Gif-sur-Yvette, France

The RF system of the ThomX* storage ring consists in a 500 MHz single cell copper cavity of the ELETTRA type, powered with a 50 kW CW solid state amplifier, and the associated Low Level RF feedback and control loops. The low operating energy of 50 – 70 MeV makes the impedances of the cavity higher order modes (HOMs) particularly critical for the beam stability. Their parasitic effects on the beam can be cured by HOM frequency shifting techniques, based on a fine temperature tuning and a dedicated plunger. A typical cavity temperature stability of ± 0.05°C within a range from 35 up to 80 °C can be achieved by a precise control of its water cooling temperature. On the other hand, the tuning of the cavity fundamental mode is achieved by changing its axial length by means of a mechanical tuner. In order to insure a fine control of the HOM frequencies, a good knowledge of their characteristics is mandatory. The main parameters of the fundamental and of the HOMs up to 4 GHz have been calculated using the HFSS and CST MWS codes. Preliminary measurements results have been obtained and show a good agreement with the simulations.
* A.Variola, “The ThomX Project”, Proceedings of IPAC2011, San Sebastián, Spain

WEPFI007

Amplitude, Phase and Temperature Stabilization of the ELSA RF System

cavity, LLRF, HOM, feedback

2717

D. Sauerland, W. Hillert, A. Roth, M. Schedler
ELSA, Bonn, Germany
D. Teytelman
Dimtel, San Jose, USA

In the stretcher ring of the accelerator facility ELSA electrons are accelerated to a maximum energy of 3.2 GeV applying a fast energy ramp of up to 6 GeV/s. In order to be able to offer higher external beam currents one has to increase the current of the internal beam in ELSA accordingly. The beam current is limited due to excitation of multi bunch instabilities which are mainly caused by higher order modes of the two PETRA cavities used for particle acceleration in the stretcher ring. To control the resonance frequency of these modes, a variable bypass of the cavities' cooling system has been installed which allows a stabilization of their temperature. With this modification, it is possible to vary the temperature of the cavities between 26 °C and 65 °C and thus to shift the higher order modes by hundreds of kHz in frequency. Additionally, first operational studies with a prototype of a FPGA based LLRF system (Dimtel) have been performed which in future will be used to stabilize the amplitude and phase of the accelerating RF fields of the cavities.

WEPFI026

Design and Commissioning of the RF System of CYCIAE 14 Cyclotron

cyclotron, cavity, low-level-rf, resonance

2759

Z.G. Yin, B. Ji, Y. Lei, P.Z. Li, G.F. Song, C. Wang, T.J. Zhang, Z.L. Zhao
CIAE, Beijing, People's Republic of China

The RF system of CYCIAE-14 consists of a set of 20kW amplifier, two 1/4λ RF cavities connected in central region, the transmission line and a set of LLRF system. The LLRF system, based on DDS and DSP, has achieved the close-loop adjustment of accelerating voltage and the resonant frequency. The RF system design for CYCIAE-14 was started in 2010, and the fabrication of the major equipments was finished in 2011. The installation and commissioning was completed in early 2012, satisfying the design requirements. This article describes the design of the RF system, and summarizes the difficulties encountered in the process of manufacture, installation and commissioning. Some of the problems caused by the transmission line and the RF leakage are analyzed, followed by the measures taken to solve these problems.

WEPFI028

RF System of the CSNS Synchrotron

cavity, LLRF, feedback, synchrotron

2765

H. Sun, W.L. Huang, X. Li, W. Long, H. Shi, C.L. Zhang, F.C. Zhao
IHEP, Beijing, People's Republic of China

The accelerator of China Spallation Neutron Source (CSNS) consists of a H− linac and a rapid cycling synchrotron (RCS). The protons injected into the RCS will be accelerated from 81MeV to 1.6GeV by the Ring RF system providing a maximum accelerating voltage of 165kV. The RF frequency sweeps from 1.02 MHz to 2.44 MHz. with a repetition rate of 25Hz. The ferrite-loaded RF cavities will be used in the ring RF system. Each cavity has own RF power tube amplifier, bias current supply and full digital LLRF control loops. The R&D of ring rf system have been completed, it compose of the prototypes of a full size ferrite loaded RF cavity, a high power tetrode amplifier, a switching type bias supply of 3000A and a full digital embedded controller of LLRF. CSNS ring RF system design and the results of the R&D will be described in this paper.

WEPFI041

Design of the RF System for the Accelerator Complex of Rare Isotope Science Project

cavity, LLRF, rfq, rf-amplifier

2794

J. Han, O.R. Choi, J.-W. Kim
IBS, Daejeon, Republic of Korea
C.K. Hwang
KAERI, Daejon, Republic of Korea

The rare isotope beam facility planned in Korea utilizes superconducting linear accelerators and a cyclotron to accelerate heavy-ion and proton beams, in which an RFQ in the injection line and superconducting cavities are the main rf components. The RF systems to power the cavities and to control the system at the low level have been designed so as to acquire high-quality beam with precise controls of rf amplitude and phase. The superconducting cavity is sensitive to various perturbations like mechanical vibration and Lorentz force detuning due to narrow bandwidth. We plan to use the rf amplifier system based on solid state device for superconducting cavities, and a tetrode tube for the final stage of RF amplifier of the RFQ accelerator. An LLRF system to control the amplitude and phase, which was built and tested on a quarter-wave resonator, will be modified to control a superconducting cavity. We plan to test the LLRF system in the superconducting rf facility abroad.

WEPFI042

Installation and Operation of the RF System for the 100 MeV Proton Linac

linac, klystron, LLRF, proton

2797

K.T. Seol, Y.-S. Cho, D.I. Kim, H.S. Kim, H.-J. Kwon, Y.-G. Song
KAERI, Daejon, Republic of Korea

Funding: This work was supported by the Ministry of Education, Science and Technology of the Korean Government.
The RF system of the 100MeV proton linac for 1st phase of KOMAC has been installed at the Gyeong-ju site. Nine sets of LLRF control system and the HPRF system including 1MW klystrons, circulators and waveguide components have been installed at the klystron gallery, and four high voltage converter modulators has been installed at the modulator room. A RF reference system distributing 300MHz LO signal to each RF control system has also been installed with a temperature control system. The requirement of RF field control is within ± 1% in RF amplitude and ± 1 degree in RF phase, and the operation of RF system will start at the end of this year after installation. The installation and operation of the RF system for the 100MeV proton linac are presented in this paper.

WEPFI043

S-band High Stability Solid State Amplifier for 10 GeV PAL-XFEL

LLRF, FEL, klystron, monitoring

2800

W.H. Hwang, J.Y. Huang, H.-S. Kang, H.-S. Lee, W.W. Lee
PAL, Pohang, Kyungbuk, Republic of Korea

In PAL, We are constructing a 10GeV PxFEL project. The output power of the klystron is 80 MW at the pulse width of 4 ㎲ and the repetition rate of 60 Hz. And the specifications of the rf phase and amplitude stability are 0.05 degrees(rms) and 0.05%(rms) respectively. The SSA(Solid State Amplifier) is used for driver of 80MW Klystron. The output power of SSA is 800W. Also, the measured rf stability of SSA output is 0.03 degrees rms and 0.025 % rms. This paper describes the microwave system and the SSA for the PxFEL.

WEPFI056

Study of the Thermo-Mechanical Behavior of the CLIC Two-Beam Modules

alignment, RF-structure, linac, collider

2818

F. Rossi, R. Mondello, G. Riddone
CERN, Geneva, Switzerland
D. Gudkov, A. Samoshkin
JINR, Dubna, Moscow Region, Russia
I. Kossyvakis
National Technical University of Athens, Zografou, Greece
K. Österberg
HIP, University of Helsinki, Finland

The final luminosity target of the Compact LInear Collider (CLIC) imposes a micron-level stability of the two-meter repetitive two-beam modules constituting the main linacs. Two-beam prototype modules have been assembled to extensively study their thermo-mechanical behaviour under different operation modes. The power dissipation occurring in the modules will be reproduced and the efficiency of the corresponding cooling systems validated. At the same time, the real environmental conditions present in the CLIC tunnel will be studied. Air conditioning and ventilation systems will be installed in the dedicated laboratory. Air temperature will be varied from 20 to 40 °C, while air flow rate will be regulated up to 0.8 m/s. During all experimental tests, the alignment of the RF structures will be monitored to investigate the influence of power dissipation and air temperature on the overall thermo-mechanical behaviour. This test program will allow for better understanding the behaviour of CLIC modules and the results will be propagated back to both numerical modelling and engineering design.

WEPFI060

Planar Balun Design with Advanced Heat Dissipation Structure for kW Level Solid-state Amplifier Module Development

coupling, impedance, storage-ring, klystron

2830

T.-C. Yu, L.-H. Chang, M.H. Chang, L.J. Chen, F.-T. Chung, M.-C. Lin, Y.-H. Lin, Z.L. Liu, C.H. Lo, M.H. Tsai, Ch. Wang, T.-T. Yang, M.-S. Yeh
NSRRC, Hsinchu, Taiwan

The power level of solid-state amplifier is continuously growing for advanced accelerator application as the RF power source. Huge amount of solid-state power amplifier (SSPA) modules can contribute several hundreds of kW RF power with high redundancy and reliability. However, with the increasing desire of RF power of single RF station, too much power modules would adversely cause larger area occupation and higher maintenance cost and complexity. Therefore, with the advancement of the RF power on single SSPA, the overall system design and configuration would become much simple and compact. However, the increasing RF of single SSPA would also bring the thermal problem at its chip as well as the output power combining balun. In this paper, kW range SSPA is developed with the novel planar balun structure with good thermal expansion property. With such new planar balun design, the SSPA can operate stably with above 1kW output RF power.

WEPFI061

Petra Cavity Vacuum RF Condition with Field Balance Mechanism for TPS Storage Ring in NSRRC

cavity, coupling, vacuum, storage-ring

2833

T.-C. Yu, L.-H. Chang, M.H. Chang, L.J. Chen, F.-T. Chung, M.-C. Lin, Y.-H. Lin, Z.L. Liu, C.H. Lo, M.H. Tsai, Ch. Wang, T.-T. Yang, M.-S. Yeh
NSRRC, Hsinchu, Taiwan

In the first stage commissioning of TPS (Taiwan Photon source) storage ring in NSRRC, two room temperature Petra cavities will be used. At this commission stage, 100mA with 950keV beam loss is estimated to have 47.5kW beam loss for each cavity. In the meanwhile, the cavity loss at the specified 1.2MV of each cavity will be about 50kW. Therefore, coupling coefficient of 2 is required. However, the initial design specification of Petra cavity has only beta of about 1.7. Hence, the modification of the input coupler is done with the enhancement of its beta as well as advanced water cooling for some heat point. Besides, due to the two-tuner system of Petra cavity, special field-balance tuner control system is also developed. In RF condition for better vacuum up to 1.4MV, some modification of the tuner mechanical structure is also done to reach high vacuum condition (lower than 5*10^-9 Torr) for storage ring requirement.

WEPFI063

Progress on the ISIS Synchrotron Low Power RF System Upgrade

cavity, synchrotron, acceleration, proton

2839

A. Seville, D.B. Allen, D. Bayley, N.E. Farthing, I.S.K. Gardner, R.J. Mathieson
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
W.L. Huang
IHEP, Beijing, People's Republic of China

The ISIS synchrotron at the Rutherford Appleton Laboratory in the UK now routinely uses a dual harmonic RF system to accelerate beam currents in excess of 230 uA to operate two target stations simultaneously. To give more stable control of the RF voltage at each of the fundamental (1RF) and second harmonic (2RF) cavities, changes have been made to the low power RF (LPRF) control systems. A new FPGA based master oscillator has been implemented using a National Instruments FlexRIO module. The replacement master oscillator has been tested with beam for the first time. This paper reports on the tests of the FlexRIO master oscillator and describes plans for the gradual replacement of the remaining parts of the LPRF system.

WEPFI066

The RF System for the MICE Experiment

cavity, LLRF, diagnostics, linac

2848

K. Ronald, A.J. Dick, C.G. Whyte
USTRAT/SUPA, Glasgow, United Kingdom
P.A. Corlett
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
A.J. DeMello, D. Li, S.P. Virostek
LBNL, Berkeley, California, USA
A.F. Grant, A.J. Moss, C.J. White
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
P.M. Hanlet
IIT, Chicago, Illinois, USA
C. Hunt, K.R. Long, J. Pasternak
Imperial College of Science and Technology, Department of Physics, London, United Kingdom
T.H. Luo, D.J. Summers
UMiss, University, Mississippi, USA
A. Moretti, R.J. Pasquinelli, D.W. Peterson, R.P. Schultz, J.T. Volk
Fermilab, Batavia, USA
P.J. Smith
Sheffield University, Sheffield, United Kingdom
T. Stanley
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
Y. Torun
Illinois Institute of Technology, Chicago, IL, USA

The International Muon Ionisation Cooling Experiment (MICE) is designed to demonstrate the effectiveness of ionisation cooling to reduce the phase space footprint of a muon beam, principally to allow the subsequent acceleration of muons for next generation colliders and/or neutrino factories. The experiment (and indeed any subsequent accelerator cooling channel based on the same principles) poses certain unusual requirements on its RF system, whilst the precision measurement of the ionisation cooling process demands special diagnostics. This paper shall outline the key features of the RF system, including the LLRF control, the power amplifier chain, distribution network, cavities, tuners and couplers, all of which must operate in a high magnetic field environment. The RF diagnostics which, in conjunction with the other MICE diagnostics, shall allow detailed knowledge of the amplitude and phase of the acceleration field during the transit of each individual Muon shall also be outlined.

WEPME002

Fast Orbit Feedback at BESSY-II: Performance and Operational Experiences

feedback, booster, status, injection

2920

R. Müller, T. Birke, M. Diehn, D.B. Engel, B. Franksen, R. Görgen, P. Kuske, R. Lange, I. Müller, A. Schälicke, G. Schindhelm
HZB, Berlin, Germany

At the 3rd generation light source BESSY II the first phase of a fast orbit feedback system(*) has been completed and put into operation in 2012. In this first phase the aim was to achieve noise suppression in the 1Hz to several 10Hz range, mostly avoiding expensive upgrades to existing hardware, such as beam position monitors and the CAN based setpoint transmission to the power supplies. Only the power supplies were replaced with newer, faster versions. This paper describes the capability of the phase-I FOFB with respect to beam motion transient suppression, low frequency damping and high frequency noise generation as well as aspects of operational integration and stability.
* Müller, R. et. al.: Installing a Fast Orbit Feedback at BESSY.
IPAC 10, Kyoto, Japan, 23 - 28 May, 2010., p. 2749-2751

Poster WEPME002 [2.720 MB]

WEPME004

A Digital Beam-Phase Control System for a Heavy-Ion Synchrotron with a Double-Harmonic Cavity System

cavity, synchrotron, feedback, dipole

2926

J. Grieser, D.E.M. Lens
TU Darmstadt, RTR, Darmstadt, Germany
U. Hartel
TEMF, TU Darmstadt, Darmstadt, Germany
H. Klingbeil, U. Laier, K.-P. Ningel, S. Schäfer, B. Zipfel
GSI, Darmstadt, Germany

Funding: Funded by GSI Helmholtzzentrum für Schwerionenforschung GmbH
For the new Facility for Antiproton and Ion Research (FAIR) at GSI Helmholtzzentrum für Schwerionenforschung GmbH, the heavy-ion synchrotron SIS18 will be operated with a double-harmonic cavity system*. The second cavity, running at twice the fundamental RF frequency, is used to lengthen the bucket which introduces nonlinearities to the control system. To damp longitudinal rigid dipole oscillations a digital feedback system consisting of a filter and an integrator is used. For the existing single-harmonic setup an FIR-filter is implemented which realizes a multiple bandpass filter with the first passband close to the synchrotron frequency. Both, the feedback gain and the passband frequency of the filter depend on the actual value of the synchrotron frequency**. It was shown by simulations and in an experiment that this setup can be transferred to a double-harmonic cavity system obtaining similar results for the region of stable feedback parameters, if the oscillation frequency of the bunch barycenter*** is considered instead of the synchrotron frequency of a linearized bucket. In this contribution the results of the simulation and the experiment are presented and compared.
*Klingbeil et al.: Phys. Rev. Special Topics - Accelerators and Beams 14, 102802, 2011
**Klingbeil et al.: IEEE Trans. on Nucl. Science, Vol. 54, No. 6, 2007
***Grieser et al.: Proc. 3rd IPAC, 2012

WEPME005

Pulsed RF Control for the P-Linac Test Stand at FAIR

linac, cavity, proton, antiproton

2929

P. Nonn, U. Bonnes, C. Burandt, F. Hug, M. Konrad, N. Pietralla
TU Darmstadt, Darmstadt, Germany
R. Eichhorn
Cornell University, Ithaca, New York, USA
H. Klingbeil, G. Schreiber, W. Vinzenz
GSI, Darmstadt, Germany
H. Klingbeil
TEMF, TU Darmstadt, Darmstadt, Germany

Funding: Supported through BMBF contract no. 06DA9024I
The p-linac will be a dedicated proton injector for antiproton production at FAIR (GSI Darmstadt). It will provide a 70 MeV/70 mA pulsed proton beam with a duty cycle of about 10^-4. Therefore the RF of the normal conducting, coupled CH cavities* will be pulsed, too. In order to test the operation of those cavities, a test stand is under construction at GSI. The RF control hard- and software for the test stand is developed at TU Darmstadt. It is based on the digital low level RF control system, which is operational at the S-DALINAC**. Hardware as well as software had to be customized, in order to achieve pulsed operation within the given limits. These customizations as well as measurements from pulsed operation will be presented.
*R. Brodhage et al. Development and Measurements on a Coupled CH Proton Linac for FAIR, IPAC'10
**M. Konrad et al. Digital base band rf control system for the… , PRL ST Accel. & Beams 15

WEPME008

Precision LLRF Controls for the S-Band Accelerator REGAE

laser, gun, LLRF, electron

2938

M. Hoffmann, H. Kay, U. Mavrič, H. Schlarb, Ch. Schmidt
DESY, Hamburg, Germany
W. Jałmużna, T. Kozak, A. Piotrowski
TUL-DMCS, Łódź, Poland

The linear accelerator REGAE (Relativistic Electron Gun for Atomic Exploration) at DESY delivers electron bunches with a few femtosecond duration for time-resolved experiments of material structure in pump-probe configuration. To achieve the desired 10 fs resolution, the Low Level RF controls for the normal conducting S-band cavities must provide field stability of 0.01% in amplitude and of 0.01deg in phase. To achieve these demanding stability a recently developed LLRF controller based on the Micro-Telecommunications Computing Architecture (MTCA.4) have been installed and commission. In this paper, we report on measurement performance of the LLRF system, the achieved stability and current limitations.

WEPME009

Recent Developments of the European XFEL LLRF System

LLRF, cavity, laser, beam-loading

2941

Ch. Schmidt, G. Ayvazyan, V. Ayvazyan, J. Branlard, L. Butkowski, M.K. Grecki, M. Hoffmann, T. Jeżyński, F. Ludwig, U. Mavrič, S. Pfeiffer, H. Schlarb, H.C. Weddig, B.Y. Yang
DESY, Hamburg, Germany
P. Barmuta, S. Bou Habib, K. Czuba, M. Grzegrzółka, E. Janas, J. Piekarski, I. Rutkowski, D. Sikora, L. Zembala, M. Żukociński
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
W. Cichalewski, K. Gnidzińska, W. Jałmużna, D.R. Makowski, A. Mielczarek, A. Napieralski, P. Perek, A. Piotrowski, T. Pożniak, K.P. Przygoda
TUL-DMCS, Łódź, Poland
S. Korolczuk, I.M. Kudla, J. Szewiński
NCBJ, Świerk/Otwock, Poland
K. Oliwa, W. Wierba
IFJ-PAN, Kraków, Poland

The European XFEL is comprised of more than 800 TESLA-type super-conducting accelerator cavities which are driven by 25 high-power multi-beam klystrons. For reliable, reproducible and maintainable operation of linac, the LLRF system will process more than 3000 RF channels. Beside the large number of RF channels to be processed, stable FEL operation demands field stability better than 0.010deg in phase and 0.01% in amplitude. To cope with these challenges the LLRF system is developed on MTCA.4 platform. In this paper, we will give an update of the latest electronics developments, advances in the feedback controller algorithm and measurement results at FLASH.

WEPME010

Patient-specific Intensity-modulation of a Slowly Extracted Beam at the HIT Synchrotron

feedback, ion, synchrotron, extraction

2944

C. Schömers, E. Feldmeier, Th. Haberer, J. Naumann, R.E. Panse, A. Peters
HIT, Heidelberg, Germany

Since 2009 more than 1100 tumour patients have been treated at the Heidelberg Ion Therapy-Centre (HIT). The HIT synchrotron produces a library of energy, focus and intensity-variable pencil beams used to deliver dose distributions of utmost conformity to irregularly shaped target volumes. The required number of particles for each volume element of the tumour, which can vary by more than two magnitudes, is applied using the rasterscan technology. The irradiation-time and thus the patient throughput are highly sensitive to the achieved spill-structure driven by RF-Knockout extraction. Presently unfavourable fluctuations of the extracted intensity due to inhomogeneous phase space distribution of the beam are present. Recently a feedback-loop coupling the dose-defining ionisation chamber in front of the patient with the RF-Exciter was implemented allowing for the adaptation of the extracted intensity to the patient-specific treatment plan in real-time. The technical implementation and the impact on the clinical operation will be discussed.

WEPME013

Development and Test of a Fully Automated PkQl Control Procedure at KEK STF

cavity, LLRF, feedback, klystron

2950

M. Omet, A. Kuramoto
Sokendai, Ibaraki, Japan
H. Hayano, T. Matsumoto, S. Michizono
KEK, Ibaraki, Japan

In order to operate the cavities near their maximum gradients, cavity input (Pk) and cavity loaded Q (QL) should be controlled individually (PkQL control) at the International Linear Collider (ILC). A manual PkQL operation procedure was developed and performed at the linear electron accelerator at the Superconducting RF Test Facility (STF), in which the beam is accelerated up to 40 MeV by two superconducting 9-cell TESLA type L band cavities. The cavity gradients were set to 16 MV/m and 24 MV/m with QL values of 110⁶ and 3·10⁶. A 6.2 mA beam with a pulse length of 154 us was used. The field stabilities in amplitude were 0.160% and 0.097% for the cavities and 0.016% for the vector sum. The stabilities without beam are 0.057% and 0.054% for the cavities and 0.009% for the vector sum. For stability improvement during beam transient an adaptive beam feedforward for beam loading compensation is under development. So far an amplitude field stability of 0.013% for the vector sum was achieved at cavity gradients of 15 MV/m and 25 MV/m (no PkQL control) during a 6.8 mA beam with a pulse length of 123 us. Furthermore a fully automated PkQL control procedure is currently developed and tested.

Poster WEPME013 [0.647 MB]

WEPME014

Progress in Development of New LLRF Control System for SuperKEKB

cavity, klystron, LLRF, pick-up

2953

T. Kobayashi, K. Akai, K. Ebihara, A. Kabe, K. Nakanishi, M. Nishiwaki, J.-I. Odagiri
KEK, Ibaraki, Japan
H. Deguchi, K. Harumatsu, K. Hayashi, T. Iwaki, J. Mizuno, J. Nishio, M. Ryoshi
Mitsubishi Electric TOKKI Systems, Amagasaki, Hyogo, Japan

For the SuperKEKB project, a new LLRF control system was developed to realize high accuracy and flexibility. It is an FPGA-based digital RF feedback control system using 16-bit ADC's, which works on the μTCA platform. The FPGA boards control accelerating cavity fields and cavity tuning, and the EPICS-IOC is embedded in each of them. The CSS-BOY was adopted for a user interface of our system. High power test of the new LLRF control system was performed with the ARES Cavity of KEKB. The obtained feedback control stability with a klystron drive was sufficient as well as the low-level evaluation result. And auto tuner control also worded successfully. The start-up sequencer program for the cavity operation and auto-aging program also worked very well. The temperature characteristics of the system depend largely on band-pass filters (BPF). We tried to tune the BPF to reduce the temperature coefficient. Consequently the temperature dependence was improved to satisfy the required stability.

WEPME015

Evaluation of the Superconducting LLRF system at cERL in KEK

LLRF, cavity, coupling, linac

2956

F. Qiu, D.A. Arakawa, H. Katagiri, T. Matsumoto, S. Michizono, T. Miura, T. Miyajima, K. Tsuchiya
KEK, Ibaraki, Japan

A low level RF (LLRF) design is being currently developed within the compact Energy Recover Linac (cERL) at KEK. One challenging task is to achieve the high amplitude and high phase stability required by the accelerating fields of up to 0.1% and 0.1°, respectively. To improve the performance of the LLRF system, a gain scanning experiment for determining the optimal controller gain was carried out on the cERL. Furthermore, as a substitute for the traditional PI controller, a more robust H∞-based multiple input multiple output (MIMO) controller was realized. This controller requires more detailed system information (transfer function or state equation), which can be acquired by using modern system identification methods. In this paper, we describe the current status of these experiments on the cERL.

WEPME016

Recent Progress of a Laser-based Alignment System at the KEKB Injector Linac

laser, alignment, linac, feedback

2959

T. Suwada, M. Satoh
KEK, Ibaraki, Japan
K. Minoshima, S. Telada
AIST, Tsukuba, Japan

A new laser-based alignment system is under development in order to precisely align accelerator components with a precision level of ±0.1 mm along an ideal straight line at the KEKB injector linac. The high-precision alignment system is strongly required for the Super B-factory at KEK. The laser-based alignment system comprises a He-Ne laser source and optical components for delivering the laser beam, and silicon photodetectors. The laser-based alignment system aligns a misalignment of a girder unit for accelerating structures while accelerator components on the girder unit are aligned with another laser tracker system with a similar precision level. A new PC-based feedback system for the laser pointing stability has been introduced in order to stabilize the transverse laser positions at the photodetector. The experimental results show that although the laser pointing stability is easily disturbed by environmental factors without the feedback system, it has been successfully applied to control the laser pointing stability within a few ten-micron-meter. In this report, the experimental investigations in the new feedback system are reported.

WEPME017

Development and Application of the Trigger Timing Watchdog System in KEK Electron/Positron Linac

linac, klystron, EPICS, electron

2962

M. Satoh, K. Furukawa, F. Miyahara, T. Suwada
KEK, Ibaraki, Japan
T. Kudou, S. Kusano
Mitsubishi Electric System & Service Co., Ltd, Tsukuba, Japan

The KEK injector linac provides electrons and positrons to several accelerator facilities. A 50 Hz beam-mode switching system has been constructed to realize simultaneous top-up injections for Photon Factory and the KEKB high- and low-energy rings, which require different beam characteristics. An event-based timing and control system was built to change the parameters of various accelerator components within 20 ms. The components are spread over a 600-m-long linac and require changes to a total of 100 timing and control parameters. The system has been operated successfully since the autumn of 2008 and has been improved upon as beam operation experience has been accumulated. The timing watchdog and alert system are indispensable for the stable and high quality beam operation. For this purpose, we developed and utilized several timing watchdog system. We will present the detail of timing signal watchdog system for the KEK injector linac.

WEPME019

Development of Beam Position Feedback Control System in KU-FEL

FEL, feedback, gun, electron

2968

H. Ohgaki, Y.W. Choi, H. Imon, T. Kii, R. Kinjo, T. Konstantin, K. Masuda, H. Negm, K. Okumura, M. Omer, S. Shibata, K. Shimahashi, K. Yoshida, H. Zen
Kyoto University, Institute for Advanced Energy, Kyoto, Japan

The stability of electron beam parameters such as position, energy etc. is very crucial for stable FEL operation. In Kyoto University MIR-FEL facility (KU-FEL), fluctuation of beam position and energy is caused by external fluctuations, such as the fluctuation in the cathode temperature of the thermionic RF-gun due to the back-streaming electrons, fluctuation of RF phase and amplitude, fluctuations of room and water temperatures, electric noises and so on. To monitor electron beam movement, we have already developed BPM system consisting of a 4-button electrode type BPM, a heterodyne detector, and CAMAC ADC in KU-FEL. By using this BPM system we have observed some correlations between external fluctuations and the beam position movements. In this conference, we will present the developed BPM system as well as the beam feedback system for stable KU-FEL operation.

WEPME022

Overview of the CSNS/RCS LLRF Control System

cavity, LLRF, feedback, beam-loading

2977

X. Li, W. Long, H. Sun, C.L. Zhang, F.C. Zhao
IHEP, Beijing, People's Republic of China

The CSNS/RCS RF system consists of 8 ferrite-loaded RF cavities (h=2), each with individual digital LLRF control electronics. The injection and extraction energy of the beam are 80MeV and 1.6GeV respectively with a repetition rate of 25Hz. The RF system is designed to provide the maximum RF voltage of 165kV. The RF frequency range is from 1.02MHz at injection to 2.44MHz at extraction. The CSNS/RCS LLRF control system is based on FPGA, and composed of 7 control loops to achieve required acceleration voltage amplitude and phase regulation. A number of prototype and the first formal system have been completed and tested. In this paper we present an overview of the LLRF control system, and some operational results.

WEPME024

Gaussian Spectrum Fiber Laser Pulses Generated in an All-normal-dispersion Cavity

laser, cavity, background, status

2983

Y. You, W.-H. Huang, C.-X. Tang, L.X. Yan
TUB, Beijing, People's Republic of China
H. Shimizu, J. Urakawa
KEK, Ibaraki, Japan

In this paper, we reported generating a broad bandwidth Gaussian shape spectrum fiber laser pulse directly in an all-normal dispersive cavity. Pulse-shaping is based on spectral filtering. The spectrum has a ~20 nm 20-dB spectrum bandwidth and it is different from the typical spectrum, of steep edge and two spikes. The Gaussian spectrum is preferred since it can be dechirped to transform-limited pulsed duration. The pulse duration corresponds to this kind of spectrum is ~315fs, and pulse energy is up to~9nJ, with a repetition rate of 18.9MHz.

WEPME025

The Surveying Data Processing of Control Network based on HLS Upgrade

survey, synchrotron, synchrotron-radiation, laser

2986

W. Wang, X.Y. He, P. Wang, S.F. Xu, Q.Y. Yao
USTC/NSRL, Hefei, Anhui, People's Republic of China

The paper introduces the data processing procedure of control network based on the HLS upgrade. The Spatial Analyzer developed by New River Kinematics was used to adjust the data of surveying, In order to check the correctness of the adjustment result, The MAA developed by IHEP was also employed to make three-dimensional adjustment as well as plane adjustment done by SURVEY adding elevation adjustment by NASEW2003. Through comparing the results adjusted by different software, the SA is demonstrated reliable. At last, the cause why different software produces different results was analyzed depending on the adjustment principle of different software.

WEPME032

Development Status of SINAP Timing System

PLC, linac, status, background

2992

M. Liu, D.K. Liu, C.X. Yin, L.Y. Zhao
SINAP, Shanghai, People's Republic of China

After successful implementation of SINAP timing solution at Pohang Light Source in 2011, the development of SINAP timing system version-II was finished by the end of 2012. The hardware of version-II is based on Virtex-6 FPGA chip, and bidirectional event frame transfer is realized in a 2.5Gbps fiber network. In event frame, data transfer functionality substitutes for distributed bus. The structure of timing system is also modified, where a new versatile EVO could be configured as EVG, FANOUT and EVR with optical outputs. Besides standard VME modules, we designed PLC-EVR as well, which is compatible with Yokogawa F3RP61 series. Based on brand new hardware architecture, the jitter performance of SINAP timing system version-II is improved remarkably.

WEPME033

Status of SSRF Fast Orbit Feedback System

feedback, EPICS, power-supply, synchrotron

2995

C.X. Yin, B.C. Jiang, L.Y. Zhao
SINAP, Shanghai, People's Republic of China

As a 3rd generation light source, Shanghai Synchrotron Radiation Facility (SSRF) is pushing the requirement of beam stability to sub-micron in the range of DC to 100Hz. A fast orbit feedback system was designed and implemented to satisfy this requirement. In this paper, the layout of SSRF fast orbit feedback system, the structure of its electronics system and its hardware and software subsystems are described. The current status of SSRF fast orbit feedback system is presented.

WEPME034

Motion Control of the Mirror Chamber

EPICS, target, focusing

2998

Z.H. Zhang, L.F. Zheng
SSRF, Shanghai, People's Republic of China
W.H. Jia, P. Liu
SINAP, Shanghai, People's Republic of China

Funding: Shanghai Institute of Applied Physics (SINAP), CAS, Shanghai 201800, P. R. China
The initial beamlines of SSRF have several mirror chambers. The motion mechanism of the mirror chamber consists of six step motors. Three vertical motors are used to achieve the height translation, the roll adjustment and the pitch adjustment. Two horizontal motors are used to achieve the horizon translation and the yaw adjustment. The mirror bending is achieved by a single motor. Except the bending, every motion needs two or three motors to work simultaneously. The VME systems are used in the control system. The EPICS (Experimental Physics and Industrial Control System) toolkits [1] are adopted to develop the control software. This paper describes how to use motor records, transform records and the EPICS database linking mechanism to form soft loops, which solve the difficulties of the complex motions perfectly. The system has been successfully applied in the mirror chambers at SSRF.

WEPME036

The Development of LLRF System at PAL

LLRF, cavity, radio-frequency, monitoring

3004

K.-H. Park, H.S. Han, Y.-G. Jung, D.E. Kim, H.-G. Lee, H.S. Suh
PAL, Pohang, Kyungbuk, Republic of Korea
J.-S. Chai, Y.S. Lee
SKKU, Suwon, Republic of Korea
B.-K. Kang
POSTECH, Pohang, Kyungbuk, Republic of Korea

The PAL has been developing the low level radio frequency (LLRF) system. The required field stabilities of the LLRF system are within ±0.75% in amplitude and 0.35° in phase in a cavity. All the hardware including RF front–end, FPGA with peripherals such as ADC, DAC, Oscillator and digital interface were assembled. The sub-modules for the RF signal processing were written by VHDL and integrated to test at the local facility. The macroblaze software processor was implemented to make the system simple in interfacing to peripherals and to secure flexibility later. This paper described the microblaze processor which was ported into the VERTEX6 FPGA. And also this paper showed the test results of the each module and integrated into the full system.

WEPME037

Fast Orbit Feedback at Taiwan Photon Source

brilliance, feedback, EPICS, storage-ring

3007

A. Bardorfer, P. Leban
I-Tech, Solkan, Slovenia
P.C. Chiu, K.T. Hsu, C.H. Kuo
NSRRC, Hsinchu, Taiwan

Low latency, distributed, Fast Orbit Feedback (FOFB) application, based on singular value decomposition, entirely implemented in FPGA, has been developed for the Taiwan Photos Source (TPS). The FOFB utilizes the latest Libera Brilliance⁺ units for measuring beam position and the Gigabit Data eXchange (GDX) modules, which take care of global orbit distribution via 6.5 Gbit/s fiber optic or passive Cu links, and provide a large orbit data history buffer. The magnet correction in a matrix form of M = V . PI( S^-1 . U^T . ( Golden-Orbit ) ) is calculated entirely in FPGA, using a massively parallel approach and sent to the magnet power supplies via 2.5 Gbit/s link. The entire FOFB calculation is distributed over 48 GDX modules and the system allows for synchronous (on/off/pause) FOFB control via external input signal. The latencies of 60 ns per BPM for orbit distribution, 1.5 us for FOFB calculation and 1.5 us for magnet data transmission have been measured at TPS test installation in November 2012. The expected total communication and FOFB calculation latency in the TPS final configuration (168 BPMs) is expected to stay within 15-20 us range.

WEPME040

Investigation to Reduce Power Overhead Required in Superconducting RF Cavity Field Control

klystron, cavity, feedback, cathode

3013

R. Zeng, S. Molloy, A. Sunesson
ESS, Lund, Sweden
A.J. Johansson
Lund University, Lund, Sweden

A power overhead of more than 25% is usually required in RF field control of klystron drived superconducting cavity, since it is much easier to implement feild control in a linear region of klystron where it is far below saturation. It however results in a reduced efficiency and more power consumption. Within ESS project it places very high demands on energy efficiency, which leads to stringent requirements on power overhead required in RF field control. Investigation on power overhead reduction in RF field control has been carried out at ESS and related simulation has been done. In this paper we will look at how close we can implement field control to the klystron saturation and discuss if it is possible to make RF field control the RF field with 10% overhead.

WEPME041

The Distance from CERN to LNGS

site, target, survey, alignment

3016

M.A. Jones, I. Efthymiopoulos, D.P. Missiaen
CERN, Geneva, Switzerland

Obviously the distance between the CNGS Target at CERN and the LNGS Opera experiment cannot be measured directly and in fact requires the combination of three independent sets of measurements: two to link underground reference points at each site to corresponding points on the surface; and a third to link the surface points at both sites. Until the Opera results raised questions about the speed at which neutrinos travelled, the main alignment concern for the CNGS beamline had been an orientation problem -to ensure that the beamline arrived to within ~100 m of its target at LNGS. GPS measurements at the two sites, and the use of gyro-theodolite measurements in the tunnel at CERN, ensured that the absolute alignment of the beamline was established to the required accuracy. New determinations of the links between the surface and the tunnel were not considered necessary until interest grew in the distance between the sites, at which point additional measurement campaigns were organised in order to further reduce the uncertainty in the distance. Details of all these campaigns and the distance estimates will be given.

WEPME047

Identification of Sources of Orbital Distortions in Corrector Space

quadrupole, alignment, feedback, damping

3034

M. Böge, M. Aiba, A. Saá Hernández, A. Streun
PSI, Villigen PSI, Switzerland

Since modern ring and linear accelerator based light sources feature fast orbit feedback (FOFB) systems which transform orbital oscillations in beam position monitor (BPM) space into corrector (C) space over a wide frequency range, most perturbations can be directly analyzed utilizing the C pattern. In C space the localization of sources of distortions is facilitated since the large (per unit phase) number of BPMs and Cs involved provides a good spatial resolution. Applications of this technique include the beam-assisted girder alignment where changes in the C pattern are interactively analyzed while girder positions are remotely altered or the beam-based alignment of quadrupole/BPM pairs where the variation of C values as the result of quadrupole variations are observed. In both cases large oscillations in BPM space are completely surpressed by the FOFB leading to well controlled and stable conditions during the measurement.

WEPME054

Girder Alignment in the Diamond Storage Ring

survey, alignment, storage-ring, quadrupole

3052

M. Apollonio, R. Bartolini, W.J. Hoffman, A.J. Rose, A. Thomson
Diamond, Oxfordshire, United Kingdom
R. Bartolini
JAI, Oxford, United Kingdom

A model of the Diamond Storage Ring describing the misalignment of its 74 girders in terms of displacements and rotations is used to predict the orbit distortions and corrector magnet strengths needed for a zero orbit. Using the data from a survey we compare the effect of a pure magnet misalignment with the natural orbit of the machine. A test with a displaced girder meant to produce a reduction in corrector strength is introduced. Comparison with data obtained from the actual move of the girder is presented and discussed.

WEPME057

Commission of the Drive Laser System for Advanced Superconducting Test Accelerator

laser, gun, monitoring, cryomodule

3061

J. Ruan, M.D. Church, D.R. Edstrom, Jr, T.R. Johnson, J.K. Santucci
Fermilab, Batavia, USA

Currently an advanced superconducting test accelerator (ASTA) is being built at Fermilab. The accelerator will consist of a photo electron gun, injector, ILC-type cryomodules, multiple downstream beam lines for testing cryomodules and carrying advanced accelerator researches. In this paper we will report the commissioning and the drive laser system for this facility. It consists of a fiber laser system properly locked to the master frequency, a regen-amplifier, several power amplifier and final wavelength conversion stage. We will also report the characterization of the whole laser system and the performance of the laser system.

WEPME059

A 4 GS/sec Instability Feedback Processing System for Intra-bunch Instabilities

feedback, pick-up, kicker, injection

3067

J.E. Dusatko, J.M. Cesaratto, J.D. Fox, J.J. Olsen, K.M. Pollock, C.H. Rivetta, O. Turgut
SLAC, Menlo Park, California, USA
W. Höfle
CERN, Geneva, Switzerland

Funding: Work supported by the U.S. Department of Energy under contract DE-AC02-76SF00515 and the US LHC Accelerator Research program ( LARP)
We present the architecture and implementation overview of a proof-of-principle digital signal processing system developed to study control of Electron-Cloud and Transverse Mode Coupling Instabilities (TMCI) in the CERN SPS. This system is motivated by intensity increases planned as part of the High Luminosity LHC upgrade. It is based on a reconfigurable processing architecture which samples intra-bunch motion and applies correction signals at a 4GSa/s rate, allowing multiple samples across a single 2ns SPS bunch. This initial demonstration system is a rapidly developed prototype consisting of both commercial and custom-designed hardware that implements feedback control on a single bunch. It contains a high speed ADC and DAC, capable of sampling at up to 4GSa/s, with a 16-tap FIR control filter for each bunch sample slice. Other system features include a timing subsystem to synchronize the sampling to the injection and the bunch 1 markers, the capability of generating arbitrary time domain signals to drive the bunch and diagnostic functions including a snapshot memory for ADC data. This paper describes the design, construction and operational experience of this system.

WEPME060

First Results and Analysis of the Performance of a 4 GS/s Intra-bunch Vertical Feedback System at the SPS

feedback, kicker, injection, damping

3070

J.M. Cesaratto, J.E. Dusatko, J.D. Fox, J.J. Olsen, K.M. Pollock, C.H. Rivetta, O. Turgut
SLAC, Menlo Park, California, USA
H. Bartosik, W. Höfle, G. Kotzian, U. Wehrle
CERN, Geneva, Switzerland

Funding: Work supported by the U.S. Department of Energy under contract DE-AC02-76SF00515 and the US LHC Accelerator Research program ( LARP)
We present experimental measurements taken from SPS machine development studies with an intra-bunch feedback channel. These studies use a digital signal processing system to implement general-purpose control algorithms on multiple samples across a single SPS bunch ( for ease of synchronization with the SPS RF frequency a sampling frequency of 3.2 GS/sec. is implemented). These initial studies concentrate on single-bunch motion, and study the vertical betatron motion as the feedback control is varied. The studies are focused on validating simulation models of the beam dynamics with feedback. Time and frequency domain results include excitation and damping of intra-bunch motion with positive and negative feedback. We present an overview of the challenges of intra-bunch feedback, and highlight methods to time-align the pickup and kicker signals within the closed-loop feedback channel.

WEPME064

Recent Development on Beam-based Alignment in RHIC

quadrupole, alignment, power-supply, dipole

3082

J. Beebe-Wang, J.M. Ziegler
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
During the 2012 polarized proton and heavy ion runs, we continued the efforts on beam-based alignment (BBA) of quadrupoles in RHIC. A complete set of BBA data of triplet quadrupoles in all interaction regions of RHIC was obtained. In addition, the measurement procedures and data analysis were improved and the corresponding codes were developed. Here we report on the results of BBA measurements, analysis, and corrections. The model sensitivity, the measurement repeatability, and the BBA accuracy limitations are also discussed. As a continuing effort, we also present application code that is under development for future BBA operations in RHIC.

THOBB101

Transverse-to-longitudinal Emittance Exchange at the Fermilab Advanced Superconducting Test Accelerator

emittance, quadrupole, simulation, cavity

3103

C.R. Prokop, P. Piot
Northern Illinois University, DeKalb, Illinois, USA
B.E. Carlsten
LANL, Los Alamos, New Mexico, USA
M.D. Church, P. Piot
Fermilab, Batavia, USA

Funding: LANL LDRD program, project 20110067DR U.S. DoE under Contract No. DE-FG02-08ER41532 with Northern Illinois University and under Contract No. DE-AC02-07CH11359 the Fermi Research Alliance, LLC.
Earlier experiments at Fermilab’s A0 Photoinjector Laboratory demonstrated successful transverse-to-longitudinal emittance exchange (EEX) using a transverse-deflecting cavity (TDC) located between two identical doglegs. Such a design has the disadvantage of transversely displacing the beam. An interesting alternative is an EEX beamline designed out of a variable R56 bunch compressor chicane. In this paper, we present design and simulation testing for a chicane-based EEX for eventual implementation at Fermilab’s Advanced Superconducting Test Accelerator. We explore several advanced EEX concepts, including bunch current profile shaping, bunch compression, and dispersion-boosting to relax the requirements on TDC power and cooling.

Slides THOBB101 [2.582 MB]

THPEA002

The Accelerator Control System at ELSA

diagnostics, electron, synchrotron, emittance

3149

D. Proft, F. Frommberger, W. Hillert
ELSA, Bonn, Germany

To fulfill the new requirements of the post-accelerator mode of the electron stretcher facility ELSA, a new computer control system was developed during the early 1990s. Providing capabilities to control and monitor the facility, it represents the top layer of a distributed control system composed of HP workstations, VME and field bus processors as well as linux based personal computer s. In addition to regular updates and improvements, the HP-UX operated part of the control system recently was ported to linux, so the outdated HP workstations could be replaced by a single linux PC. All reference values, for example the betatron tune or the extraction energy, can be specified using a window-based graphical user front end. They are directly computed to hardware compatible representations. Vice versa, measured beam parameters, e.g. the transversal beam emittance, are displayed for easy user access, allowing real time diagnostics. This abstraction layer allows for an intuitive approach to machine operation, requiring no detailed knowledge of the hardware implementation. In this contribution, the design principles and implementation at different layers of the control system are presented.

THPEA003

Use of FPGA-based Configurable Electronics to Calibrate Cavities

synchrotron, LLRF, ion, heavy-ion

3152

S. Schäfer, A. Klaus, H. Klingbeil, B. Zipfel
GSI, Darmstadt, Germany
U. Hartel, H. Klingbeil
TEMF, TU Darmstadt, Darmstadt, Germany

At the GSI Helmholzzentrum für Schwerionen-forschung GmbH the accuracy requirements for synchrotron rf cavities have strongly increased in the last years, especially for multi-harmonic operation. For heavy-ion acceleration the amplitude and phase have to be well adjusted over a whole machine cycle. In order to compensate small deviations induced by low-level rf components (LLRF) and transmission lines in the control paths, a calibration electronic (CEL) with a characteristic map was developed. It is a real-time module which is based on modern FPGA (Field Programmable Gate Array) technology and adaptable to special cavities with various physical dependencies (e.g. attenuation, dispersion, temperature drift, aging etc.). The hardware and software architecture of this CEL module are presented here.

THPEA004

Precise Verification of Phase and Amplitude Calibration by means of a Debunching Experiment in SIS18

target, cavity, bunching, injection

3155

U. Hartel, H. Klingbeil
TEMF, TU Darmstadt, Darmstadt, Germany
J. Grieser, D.E.M. Lens
TU Darmstadt, RTR, Darmstadt, Germany
H. Klingbeil, U. Laier, K.-P. Ningel, S. Schäfer, B. Zipfel
GSI, Darmstadt, Germany

Funding: Work supported by the GSI Helmholtzzentrum für Schwerionenforschung GmbH
Several new rf cavity systems have to be realized for the FAIR synchrotrons and for the upgrade of the existing GSI synchrotron SIS18*. For this purpose, a completely new low-level rf system architecture** has been developed, which is now used in SIS18 operation. Closed-loop control systems stabilize the amplitude and the phase of the rf gap voltages. Due to component imperfections the transmission and the detection of the actual values lead to systematic errors without countermeasures. These errors prohibit the operation of the rf systems over the whole amplitude and frequency range within the required accuracy. To compensate the inevitable errors, the target values provided by the central control system are modified by so-called calibration electronics*** modules. The calibration curves can be measured without the beam, but the desired beam behaviour has to be verified by experiments. For this purpose, a debunching scenario was selected as a SIS18 beam experiment that proved to be very sensitive to inaccuracies. In this contribution the results of this experiment are presented, showing for the first time at GSI by beam observation that the accuracy requirements are met based on predefined calibration curves.
* “FAIR - Baseline Technical Report,” Volume 2, Accelerator and Scientific Infrastructure, (2006).
** Klingbeil et al.: Phys. Rev. ST Accel. Beams 14, 102802, 2011.
*** S. Schaefer et al., “Use of FPGA-based Configurable Electronics to Calibrate Cavities,” THPEA003, these proceedings.

THPEA006

!CHAOS Historical Engine

insertion, simulation

3158

M. Mara, A. Paoletti
Istituto Nazionale di Fisica Nucleare, Amministrazione Centrale, Frascati, Italy
C. Bisegni, G. Di Pirro, L.G. Foggetta, G. Mazzitelli, A. Stecchi
INFN/LNF, Frascati (Roma), Italy
L. Catani, F. Zani
INFN-Roma II, Roma, Italy

!CHAOS is an INFN project aimed at creating the communication framework and the services needed for the definition of a new control system standard, mainly addressed to large experimental apparatus and particle accelerators. !CHAOS is under test at DAΦNE accelerator and has been developed to overcome the strong requirements throughput of new accelerators, like superB. One of the main components of the framework is the historical engine (HST Engine), a cloud-like environment optimized for the fast storage of large amount of data produced by the control system’s devices and services (I/O channels, alerts, commands, events, etc.), each with its own storage and aging rule. The HST subsystem is designed to be highly customizable, such to adapt to any desirable data storage technologies, database architecture, indexing strategy and fully scalable in each part. The architecture of HST Engine and the results of preliminary tests for the evaluation of performance are presented.

THPEA010

Design and Implementation of the Remote Control System of the Digital Magnet Power Supply of China Spallation Neutron Source

power-supply, EPICS, status, simulation

3167

X. Wu, Y.C. He, J. Liu, C.H. Wang, J.C. Wang
IHEP, Beijing, People's Republic of China

The magnet power supplies of the China Spallation Neutron Source (CSNS) can be classified into three types: rapid cycling synchrotron (RCS) resonant power supplies, fast response power supplies and DC power supplies. All of the magnet power supplies are controlled by the intelligent controller called Digital Power Supply Control Module (DPSCM), which can regulate the current and voltage circuit. The DPSCM is developed by the power supply group. It has two RS232 communication interfaces. All the command setting and reading power parameters are transmitted by Modbus protocol. Therefore, we made the communication protocol based on Modbus RTU between the remote control system and the DPSCM. This paper introduces the design of the remote control interface to the DPSCM. We developed EPICS IOC applications and real-time database on MOXA embedded serial device DA710 and OPIs using Control System Studio (CSS) according to different kinds of the power supplies. We have tested the remote control system with these kinds of power supplies. The test result shows that the remote control system is stable and reliable and it can basically meet the requirements of power supply system and physicists.

THPEA011

WPF Based EPICS Server and its Application in CSNS

EPICS, LLRF, linac, PLC

3170

Y.L. Zhang, G. Lei
IHEP, Beijing, People's Republic of China

The control system of China Spallation Neutron Source(CSNS) is under construction based on EPICS. The Linac low level RF(LLRF) local control program running on a local control PC uses Windows Presentation Foundation( WPF) as its development tool and uses the C# codes to implement the functionality. The Linac LLRF control system is non-EPICS, so the Linac LLRF local variables can’t be accessed directly from EPICS. Therefore we need to port the Linac LLRF local control system to EPICS. This paper presents the WPF base EPICS server and its application in CSNS.

THPEA016

EPICS Driver for Phoenix Contact Redundant PLC

PLC, EPICS, status

3176

G. Liu, C. Li, J.Y. Li, J.G. Wang, W. Xu, K. Xuan
USTC/NSRL, Hefei, Anhui, People's Republic of China

The RFC 460R PLC from Phoenix Contact is a high-performance controller that has been extended to offer redundancy functionality. This redundancy functionality is vital for uninterrupted processes in complex systems and large plants. In order to integrate this product into EPICS environment, an EPICS Driver is developed. This driver is intended to connect a pair of RFC 460R redundant PLCs via TCP/IP to an EPICS IOC. In this paper, the communication mechanism, software implementation and the test results of a prototype system will be described.

THPEA017

Based on Channel Archiver of EPICS to Realize SSC-LINAC System Efficiently Beam Tuning

linac, EPICS, ion, status

3179

S.Z. Gou, M. Yue, W. Zhang
IMP, Lanzhou, People's Republic of China

In order to improve running efficiency of accelerator, shorten the time of changing accelerator beam is key link and it should be considered how to accelerate the ion to specific energy quickly and accurately. We will discuss how to use years of heavy ion accelerator operation data to generate a set of virtual accelerator equipment data for specific ion and energy, load to all the accelerator equipment fast. EPICS provide Channel Archiver tools that can achieve and store data from the IOC equipment operation information. In this study, we use Archive Engine tool and Oracle to combine data acquisition function and data management function. Firstly store the Archive Engine acquisition data into Oracle database, and then according to the data to create accelerator system operation snapshot as the basis for beam tuning. The snapshot data includes all equipment state and parameters at special time in accelerator operating. When the ion is to be changed, related snapshot in Oracle database will be retrieved and loaded to all the equipment and to realize efficiently beam tuning.

THPEA018

Design of an Integrated Platform based on CSS and MATLAB for SSC-LINAC System Controlling and Data Analysis

EPICS, linac, power-supply, vacuum

3182

M. Yue, S.Z. Gou, W. Zhang
IMP, Lanzhou, People's Republic of China

CSS is the abbreviation of Control System Studio and is widely used in particle accelerator experiments area. Based on Eclipse, it is a collection of tools which can display details of the PV, show alarm state, as well as the function of data browsers, archive engine and so on. CSS offers an integrated approach to build a control system. We have recently developed a control and monitor system for the SSC-LINAC system to control and monitor power supply, vacuum, high frequency, and other accelerator equipments. In the area of accelerator controlling, we often need to do some mathematical operations like Fourier transform of the monitored data to get some accuracy performances of interested equipments. Unfortunately, CSS cannot satisfy this requirement. It is well known that MATLAB plays very well in data process and provides many mathematical tools. If we can combine these two tools together, we can get better control strategy. In the presentation, we will discuss the design of this integrated platform to implement the display, control and data process.

THPEA019

A Method of Implementing HIRFL-CSR Chopper Controls

heavy-ion, ion, storage-ring, target

3185

K. Gu, S. An, X.J. Liu, W. Zhang
IMP, Lanzhou, People's Republic of China

A method of implementing controls of chopper for HIRFL-CSR (Heavy Ion Research Facility of Lanzhou and Cooler Storage Rings) is introduced. This method is based on an ARM and DSP co-operation system. The control algorithm of this method is based on a data structure which is defined and implemented in the DSP module. Output data is created by the control algorithm and the actually pulse output is triggered by a timer which is achieved through a logic circuit actualized in a FPGA chip. The results show that the method is flexible and the control system matches the chopper regulating requirements.

THPEA020

The Design for Presetting Data Automatically in HIRFL Power Supply Control System

power-supply, LabView, heavy-ion, cyclotron

3187

X.J. Liu, Y. Chen, K. Gu, A. Shi, J.Q. Wu, F. Yang, W. Zhang
IMP, Lanzhou, People's Republic of China

This article introduces the structure of power supply in HIRFL(Heavy Ion Research Facility in Lanzhou) and designs a program which can preset power supply data automatically. We use Labview which is produced by NI Corporation to read Excel, access the Oracle database and send the generated instructions to power supply controllers. This program brings great convenience to physicists. It is used in SSC(Separated Sector Cyclotron) power supply system. The result shows that we can preset data quickly and accurately.

THPEA021

A Platform Control System for 320 kV HV Platform

high-voltage, power-supply, ion, LabView

3189

W. Zhang, K. Gu, J.Y. Li, X.J. Liu
IMP, Lanzhou, People's Republic of China

This article describes the platform control system applied to the Chinese Academy of 320KV HV platform for highly charged ions. This system is composed of the hardware and the software. The hardware is composed of the network controller based on ATmega128 core chip. Our control group has designed the network controller for controlling the different types of equipment on the platform. The control system achieves the reliability, stability control of the different types of equipment on the HV platform, and control of the network, improve operational efficiency. The software uses NI Corporation's LABVIEW to program user interface. We have established for the application modules of the network controller in the LABVIEW and realized the optimization of the network controller to configure and use. The platform control system has run three years in the 320KV HV platform.

THPEA022

The Remote Control System for LAPECR1

ion, ion-source, power-supply, high-voltage

3192

W.X. Zhou, F.Y. Lin, J.F. Luo, Y.Y. Wang, J. Yin, Y.J. Yu, D.T. Zhou
IMP, Lanzhou, People's Republic of China

In order to support the debug of LAPECR1(Lanzhou All Permanent Magnet ECR Ion Source No.1) which merely provides H⁺ beam for HIRFL(Heavy Ion Research Facility in Lanzhou), a control system was realized in November 2011. The control system is composed of some controllers, a control-software and Intranet which is established by a switch. All of the controllers can access to Intranet directly or through serial-switch. And the controllers of the HV power and motor were designed by us. A IPC(Industrial Personal Computer) could control all of the equipments through Intranet. For the software of the system, it is designed using C++. And it could show the important data in the form of spectrum for the purpose of analysis and debug. The control system can acquire data and send command from/to the corresponding equipment.

THPEA024

The Control System of the SDUV-FEL Test Facility

FEL, EPICS, PLC, power-supply

3195

J.G. Ding, S.M. Hu, G.Y. Jiang, H.F. Miao, H. Zhao, H.J. Zhu
SINAP, Shanghai, People's Republic of China

At SINAP, the Shanghai deep ultraviolet FEL test facility (SDUV FEL) was integrated to test the FEL key technologies and principles. The facility was constructed based on the existed SINAP 100MeV LINAC with modifications of cathode gun replacement and magnet compressor segment increment, extension of the undulator section, and the seeded laser system. The control system of the facility has been developed which upgraded and extended from the existed LINAC control system. The system was integrated based on the EPICS toolkit, consists of several subsystems of magnet power supply control, timing, vacuum monitor, RF control, undulator gap adjustment, and machine protection system. In this paper, the SDUV FEL control system is introduced. Solutions of equipment control, hardware and software implementations, and system integrations are described in details.

THPEA026

Radiation Safety Interlock System for DCLS

radiation, electron, monitoring, dipole

3198

G. Wang, S. Liu, J.J. Lu, X. Xia, J.Q. Xu, Y. Xu, F. Yang
SINAP, Shanghai, People's Republic of China

Dalian Coherent Light Source (DCLS) is in the design phase currently and will be constructed in Dalian from 2013. It is a seeded HGHG-FEL, mainly consisting of one 300 MeV electron linear accelerator and one undulator. Radiation safety is one of the most important tasks for Dalian FEL. Radiation safety interlock system (RSIS) is designed to prevent personnel exposure to high radiation levels, based on the As Low As Reasonably Achievable (ALARA) principle. RSIS controls access to the radiation protection areas and monitors safety devices. Only if all the radiation safety conditions are satisfied, then the facility will be permitted to operate. Once any condition is broken, RSIS will send a signal to stop the electron beam immediately to guarantee radiation safety. The core component of RSIS utilizes Programmable Logic Controller (PLC), which is a proven and reliable technology in the field of industrial automatic control. All safety-relevant functions of RSIS are implemented with fail-safe components. The hard wiring cable of the peripheral signals for the safety-relevant functions is redundant. The safety interlock signals are sent via a fail-proof protocol and transferred redundantly.

THPEA028

Embedded EPICS Controller in Inserting Devices of SSRF

EPICS, PLC, insertion, insertion-device

3204

G.Y. Jiang
SSRF, Shanghai, People's Republic of China
G.H. Chen
SINAP, Shanghai, People's Republic of China

SSRF is the first homemade third-generation of synchrotron radiation light source in China. In the first stage of SSRF, 7 beamlines have been built. Among of them, 5 beamlines have used inserting devices (IDs) including both of wigglers and undulators. To support stable and long life beam, the control part of these IDs must focus on high stability and high precision. Thus, Simens PLC, which has been widely used in industrial control fields, was used as local device controllers to control the motors. About upper layer control, we adopted a kind of embedded EPICS controller to implement the control of correction coil power supplies and PLC. This embedded EPICS controller is based on a commercial Ethernet/Serial converter which running MontaVista linux as its operation system. Beyond this, EPICS IOC Core program and several kinds of device control drivers were integrated to it. After several months using, the whole system works stably. Details of the necessary integration work and operation performance will be discussed in this paper.

THPEA030

Improved Vector Modulator Card for MTCA-based LLRF Control System for Linear Accelerators

LLRF, power-supply, monitoring, radio-frequency

3207

I. Rutkowski, K. Czuba, M. Grzegrzólka
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
D.R. Makowski, A. Mielczarek, P. Perek
TUL-DMCS, Łódź, Poland
H. Schlarb
DESY, Hamburg, Germany

Modern linear accelerators require high-precision RF field regulation of accelerating cavities. A critical component to achieve high-precision in the feedback loop a Low Level Radio Frequency (LLRF) controller is the vector modulator driving the high power RF chain. At FLASH, the Free Electron Laser in Hamburg and European XFEL the LLRF controls are based on MTCA.4 platform. This paper describes the concept, design and performance of an improved vector modulator module (DRTM-VM2). It is constructed as Rear Transition Module (RTM). The module consists of digital, analog, diagnostic and management subsystems. FPGA from Xilinx Spartan 6 family receives data from control module (AMC) using Multi-Gigabit Transceivers (MGTs). The FPGA controls the analog part which includes fast, high-precision DACs, I/Q modulator chips, programmable attenuators, power amplifier and fast RF gates for external interlock system. Pin assignment on the Zone3 connector is compliant with digital class D1.2 recommendations proposed by DESY. The design has been optimized for mass production and for easy extends to wider frequency range. Electronic switches offer software configuration of power and clock sources.

THPEA031

REGAE LLRF Control System Overview

electron, LLRF, laser, feedback

3210

I. Rutkowski, L. Butkowski
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
M. Hoffmann, H. Schlarb, Ch. Schmidt
DESY, Hamburg, Germany

The linear accelerator REGAE (Relativistic Electron Gun for Atomic Exploration) at DESY delivers electron bunches with a few femtosecond duration for time-resolved investigation of material structures in pump-probe configuration. To achieve sub-10fs resolution, the Low Level RF controls for the normal conducting S-band cavities must provide field stability of .005% in amplitude and of .005deg in phase. To achieve these demands, the recently developed LLRF control modules based on the Micro-Telecommunications Computing Architecture (MTCA.4) platform are used. For precise field detection and control a rear transition module (DRTM-DWC8VM1) housing 8 down-converters and 1 vector-modulator has been developed. The down-converted signals are transmitted to low-noise ADCs on an advanced mezzanine card (SIS8300L) with two high speed DACs driving the vector-modulator. The on board FPGA device runs the advanced control algorithms with minimum latency. Shot-to-shot learning feed forward and ultra-fast analog and digital feedbacks are applied. In this paper, the first results of the new RTM-AMC module pairs are presented together with the achievements and limitations on the RF field stability.

THPEA032

Software for Power Supplies Control of the NSLS-II Booster Synchrotron

booster, status, EPICS, monitoring

3213

P.B. Cheblakov, A.A. Derbenev, S.E. Karnaev, S.S. Serednyakov
BINP SB RAS, Novosibirsk, Russia
M.A. Davidsaver, Y. Tian
BNL, Upton, New York, USA

The booster synchrotron of the NSLS-II light source at Brookhaven National Laboratory (BNL) provides electron beam acceleration from 200 MeV up to 3 GeV in 300 ms. This imposes strict conditions on both accuracy of control and synchronization of ramping Power Supplies (PS). Hardware part of PS controls are based on electronics specially developed at BNL and includes Power Supply Controllers (PSC) and Power Supply Interfaces (PSI). The former represents digital part of hardware and implements low-level logic (generating ramp functions, simple data verification and data acquisition), communication with control system software and PSI. The latter is an analogue part of entire system and it performs generation and acquisition analogue and digital signals by a set of on-board DACs, ADCs and digital inputs/outputs. The PSC and the PSI are connected by digital fibre optic link for electrical decoupling. This paper describes software for the booster synchrotron PSs control which is based on EPICS and includes a specially designed electronics configuration, a set of programs to manage ramp functions and to control different types of power supplies, both pulsed and ramping.

THPEA034

ESS Integrated Control System Integration Support and the Agile Methodology Proposal

monitoring, EPICS, target, vacuum

3219

M. Reščič
Cosylab, Ljubljana, Slovenia
L. Fernandez, A. Nordt
ESS, Lund, Sweden

The stakeholders of the ESS Integrated Control System (ICS) reside in four main parts of the ESS machine: accelerator, target, neutron instruments and conventional facilities. In order to maintain and support the standardized hardware and software platforms for controls all of the stakeholders' integration requirements and efforts must be strictly harmonized. This called for a decision by the ICS to perform the majority of the work in a package titled 'Integration Support', ranging from FPGA code development to EPICS integration. This exposes a high number of interfacing systems and devices and planning of such activities for each system make the standard waterfall planning model highly inefficient and risky. In order to properly address the planning risks the agile methodology is proposed - from product owners and teams to scrums and sprints, everything to offer a better and more efficient integration support to controls stakeholders.

THPEA038

ESS Naming Convention

target, linac, neutron, vacuum

3222

K. Rathsman, G. Trahern
ESS, Lund, Sweden
J. Malovrh Rebec, M. Reščič, M. Vitorovic
Cosylab, Ljubljana, Slovenia

The European Spallation Source is an intergovernmental project building a multidisciplinary research laboratory based upon thermal neutrons. The main facility will be built in Lund, Sweden. Construction is expected to start 2013 and the first neutrons will be produced in 2019. The ESS linac will deliver 5 MW of power to the target at 2.5 GeV, with a nominal current of 50 mA. The ESS Naming Convention is based on a standard, originally developed for the Super Superconducting Collider (SSC) and later adopted by other large research facilities, e.g. the Spallation Neutron Source (SNS), Facility for Rare Isotope Beams (FRIB), International Thermonuclear Experimental Reactor (ITER), and the Continuous Electron Beam Accelerator Facility (CEBAF). The ESS Naming Convention was agreed upon and approved at a very early stage of the ESS project in order to establish a standard before names started to evolve. The main scope was to standardise meaningful, yet short and mnemonic signal and device names. The present paper describes the naming convention, the site wide implementation at ESS and associated web based tools.

THPEA042

TREC: Traceability of Radioactive Equipment at CERN

radiation, HOM, monitoring, background

3234

M.P. Kepinski, L. Bruno, Ch. Delamare, S. Mallon Amerigo, P. Martel, S. Petit, T. Schmittler, M.J.S. Tavlet, D. Widegren
CERN, Geneva, Switzerland

Activated accelerator components are frequently removed from service due to changes in design, configuration or maintenance work. Safe and effective management of such components is a necessity. Moreover, local authorities require the tracking of this equipment: any piece of equipment or waste which has been in a potentially radioactive area must be controlled by a radio protection responsible before leaving the accelerator premises. CERN must also be able to prove that the required measurements have been done and are properly stored in a computerized system. TREC is the official system used at CERN to trace potentially radioactive equipment. It replaces paper work by electronic data, manual phone calls by automatic email notifications and helps to enforce CERN safety rules. Some of the major benefits are the reduction of the delays related to equipment movements (from installation to workshops or waste storage areas) as well as increased personal safety. The system is fully integrated with the CMMS* tools used at CERN to ensure the complete equipment lifecycle’s traceability.
*CMMS: Computerized Maintenance Management System

THPEA043

An Equipment Hub for Managing a Small Town and a Complex Machine

radiation, coupling, status, collider

3237

P. Martel, A. Alexandre Metola, Ch. Delamare, M.P. Kepinski, S. Mallon Amerigo, L. Pater, S. Petit, D. Widegren
CERN, Geneva, Switzerland

Effective maintenance of the accelerators’ complex is vital for CERN’s mission. While this work is highly dependent on operational planning and constraints, it also needs to be coordinated with the maintenance of the infrastructure where the complex is embedded. The nature and degree of the logistics problems that arise from this interdependence cannot be handled by partial, decoupled solutions from each of the stakeholders. CERN’s Enterprise Asset Management system is the central hub where all relevant data about equipment and its maintenance is kept. It is also where data and documents about the manufacturing, installation, safety inspection, radiation measurements, disposal, etc. of the scientific equipment reside. This hub allows the effective sharing of consistent equipment data, accessed by a large number of people and systems, and supplies a wide range of interfaces – ranging from the user in the field with no access to a desktop computer, to scheduling systems that need to interact with it through Web services; this is achieved by means of a series of systems, tools and mechanisms, all dedicated to different needs but working on the same data and sharing common policies.

THPEA048

The FPGA-based Power Monitoring System for TPS Facility

monitoring, factory, LabView, resonance

3252

C.S. Chen, Z.-D. Tsai
NSRRC, Hsinchu, Taiwan

There are more and more non-linear electronic equipments such as inverters using in facility nowadays. These non-linear electronic equipments let us achieve energy saving, but induce other electrical pollution to the whole power grid in contrast. How to monitor the electrical noises from these non-linear equipments becomes an important issue. In this article, a set of power quality monitoring system based on FPGA and PAC has been built because of the programmability and fast processing speed. By using this monitoring system, any abnormality in power system and its spectrum will be recorded thoroughly. On the other hand, the maintainer could follow the trace of noise and then propose a suitable solution to eliminate the electrical interference too.

THPEA049

Implementation of the EPICS Data Archive System for the TPS Project

EPICS, GUI, synchrotron, LabView

3255

Y.-S. Cheng, Y.-T. Chang, J. Chen, P.C. Chiu, K.T. Hsu, C.H. Kuo, C.Y. Liao
NSRRC, Hsinchu, Taiwan

The EPICS framework was chosen as control system infrastructure for the new project of 3 GeV synchrotron light source (Taiwan Photon Source, TPS). Various control system prototypes of TPS with the EPICS mechanism have been gradually built and tested. One EPICS archive system is necessary to be developed to record various machine parameters and status information for long time logging. The archive system of CSS (Control System Studio) which named BEAUTY (Best Ever Archive Toolset, yet) was built to be used as the TPS data archive system in 3rd quarter of 2012. An archive engine takes PV data from EPICS IOCs via channel access, and stores them in the data storage. The PostgreSQL RDB (Relational Database) was adopted as the data storage for the BEAUTY. Both the historic PVs data and the archive engine configuration are saved into the same RDB. The archived data can be retrieved in a form of graphical representation using the CSS-based data browser. Taking the performance and redundancy into considerations, the storage servers and RDB table structures are tuned relatively. The efforts will be described at this report.

THPEA050

Power Supply Control and Applications Development for the TPS Storage Ring Quadrupole and Sextupole Magnet

quadrupole, power-supply, sextupole, EPICS

3258

Y.-S. Cheng, J. Chen, P.C. Chiu, K.T. Hsu, C.Y. Liao, C.Y. Wu
NSRRC, Hsinchu, Taiwan

The TPS intermediate power supply for storage ring quadrupole and sextupole magnets with current rating 250 Amp will be equipped with Ethernet interface. The quadrupole power supply is 18bit with higher stability than sextupole with 16 bits, and have internal data buffer for post-mortem capability. The dedicated IOCs are built individually at the 24 cPCI platforms to manipulate the devices of the 24 cells of storage ring respectively. Each IOC is used to control 10 quadrupole magnet power supplies and 7 sextupole magnet power supplies. The GUIs of storage ring quadrupole and sextupole power supplies controls were implemented by the EDM toolkit. The client console can use the specific EDM pages to access power supplies via PVs channel access. The measured currents of quadrupole and sextupole power supplies were read back for observing performance. Some applications, like the degauss process, boot function and etc, are also developed with the specific toolkit. The efforts will be summarized at this report.

THPEA053

Data Acquisition and Monitoring for TPS SRF Module Horizontal Test

SRF, EPICS, monitoring, cavity

3264

Y.-H. Lin, L.-H. Chang, M.H. Chang, L.J. Chen, F.-T. Chung, M.-C. Lin, Z.L. Liu, C.H. Lo, M.H. Tsai, Ch. Wang, M.-S. Yeh, T.-C. Yu
NSRRC, Hsinchu, Taiwan
M.H. Tsai
NTUT, Taiwan

Three KEKB-type single-cell SRF modules were shipped to NSRRC before the end of 2012. The horizontal test of the first KEKB-type SRF module has been already finished in January of 2013. While the horizontal tests for the next two SRF module will be completed in May and August of this year. This article introduces the data acquisition and monitoring systems during the SRF horizontal test in NSRRC.

THPEA055

NESTOR Facility Control System

storage-ring, power-supply, monitoring, vacuum

3267

D.V. Tarasov, V.N. Boriskin, I.M. Karnaukhov, D. Korzhov, V.N. Ljashchenko, A. Mytsykov, A.A. Shcherbakov, V.L. Skirda, V.I. Trotsenko, A.Y. Zelinsky
NSC/KIPT, Kharkov, Ukraine

The general principles of the NESTOR facility control system are presented in the paper. The main features of the systems such as magnetic, vacuum, diagnostic, Rf etc. concerning the control and monitoring are discussed. The first results of the system implementation are presented.

THPEA059

Database for Accelerator Modeling

lattice, simulation, monitoring, extraction

3273

C.P. Chu, J. Wu
SLAC, Menlo Park, California, USA
D. Dohan, G. Shen
BNL, Upton, Long Island, New York, USA
H.H. Lv
IHEP, Beijing, People's Republic of China
Y. Zhang
FRIB, East Lansing, Michigan, USA

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661.
A database for model data is design for the Facility for Rare Isotope Beams (FRIB) Project. The database schema design takes most general approach and is not limited to FRIB models. Programmatically access to the database can be done through a set of Application Programming Interfaces (APIs). Initial data population demonstrates that the database is suitable for XAL application framework. The model database is also part of a collaboration for complete database needs among various domains across an accelerator.

THPEA060

LLRF System for LCLS-II at SLAC

LLRF, klystron, feedback, linac

3276

Z. Geng, B. Hong, K.H. Kim, R.S. Larsen, D. Van Winkle, C. Xu
SLAC, Menlo Park, California, USA

Funding: Work supported by US Department of Energy Contract DE AC03 76SF00515
After LCLS-I successfully delivering the full operation for users, SLAC has been approved to build the second Linac Coherent Light Source, LCLS-II, which makes use of another third of the 2-mile long Linac from Sector 10 to Sector20. The LLRF System will use mTCA (Micro Telecommunication Computing Architecture) to replace the VME system for LCLS-II injector and some key stations along the LINAC. The faster data acquisition and more powerful FPGA and CPU in the mTCA system enable the LLRF system to extend its control ability to a 2.5 μsec beam pulse rate of 360Hz. The new LLRF system is more compact and has the capability of low latency intra-pulse feedback to reduce fast phase and amplitude jitter during a single pulse. The prototype of the mTCA based LLRF control system has been operating at RF station 28-2 in LCLS-I. Detailed design structure and the prototype experimental results will be presented that demonstrate the system meets the exacting phase and amplitude stability requirements for LCLS-II.

THPEA061

EPICS Accelerator Control System for the IAC-RadiaBeam THz Project

EPICS, power-supply, linac, HOM

3279

A. Andrews, B.L. Berls, T. Downer, C.F. Eckman, K. Folkman, Y. Kim, C. O'Neill, J. Ralph
IAC, Pocatello, IDAHO, USA
P. Buaphad, Y. Kim
ISU, Pocatello, Idaho, USA

The Idaho Accelerator Center (IAC) of Idaho State University has been operating a 44 MeV L-band linac for various nuclear physics related applications. However, for the past several years, this research has been done without the aid of a modern computer based control system. To obtain a better reproducibility and stability in operation, the EPICS accelerator control system has been applied to control various components of this linac. This has been done for the purpose of a joint THz research project between IAC and RadiaBeam that was performed in November 2012. This paper describes the development of the EPICS accelerator control system used during this joint THz research experiment.

THPEA063

NSLS II Injector Integrated Testing

target, booster, linac, diagnostics

3285

G.M. Wang, B. Bacha, A. Blednykh, E.B. Blum, W.X. Cheng, J. Choi, L.R. Dalesio, M.A. Davidsaver, J.H. De Long, R.P. Fliller, W. Guo, K. Ha, H.-C. Hseuh, Y. Hu, W. Louie, M.A. Maggipinto, D. Padrazo, T.V. Shaftan, G. Shen, O. Singh, Y. Tian, K. Vetter, F.J. Willeke, H. Xu, L. Yang, X. Yang
BNL, Upton, Long Island, New York, USA
P.B. Cheblakov, A.A. Derbenev, A.I. Erokhin, S.M. Gurov, R.A. Kadyrov, S.E. Karnaev, E.A. Simonov, S.V. Sinyatkin, V. Smalyuk
BINP SB RAS, Novosibirsk, Russia

The NSLS-II is a state of the art 3 GeV synchrotron light source under construction at Brookhaven National Laboratory. Since 2012, the injector system gradually moves to the commissioning stage. It occurs after group people efforts on optics design, equipment specifications, construction and tests, assembly, installation and alignment. It is very important and exciting. To make the commissioning smooth and efficient, an important effort was put on the sub-system integration test to make sure the device function along with utility, timing system and control system, to calibrate diagnostics system and to debug high level application with simulated beam signals and required hardware. In this paper, we report our integration test experience and related control system software development.

THPFI008

Experience and Benefits from PLM-based Parts Management at European XFEL

cavity, linac, factory, undulator

3306

L. Hagge, J.A. Dammann, S. Eucker, A. Frank, J. Kreutzkamp, D. Käfer, D. Szepielak, N. Welle
DESY, Hamburg, Germany

DESY has developed a parts management solution, which is used in the series fabrication of accelerator components for the European XFEL. The parts management solution stores assembly instructions and drawings for each component, and it tracks the assembly progress of each individual component. It offers procedures for quality inspections, for handling non-conformities and for managing changes, and it tracks the current whereabouts and the entire history of each part. The solution is based on DESY's Product Lifecycle Management (PLM) System and integrates several laboratories and suppliers. The poster shows how parts management is used at the European XFEL in the production of the super-conducting rf cavities, in the assembly of the cryomodules and in the assembly of the undulators, and discusses experience and benefits.

THPFI018

The Design and Construction of Stripping Probe System for CYCIAE-100

extraction, proton, vacuum, cyclotron

3333

Shizhong. An, F.P. Guan, P.Z. Li, L.P. Wen, H.D. Xie, Z.G. Yin, T.J. Zhang
CIAE, Beijing, People's Republic of China

A 100 MeV H⁻ compact cyclotron is being constructed in China Institute of Atomic Energy (CYCIAE-100). 75 MeV - 100 MeV proton beams with 200 μA beam intensity will be extracted in dual opposite directions by charge exchange stripping devices. Two stripping probes with carbon foils are inserted radially in the opposite direction from the main magnet pole and the obtained two proton beams after stripping foil are transported into the crossing point in a combination magnet center separately under the fixed main magnetic field. Because of the large energy range of the extracted beam, the stripping probe system is the most critical and complicated device in the dual extraction. In order to save the foil changing time, the structure of the foil changing system in the vacuum is adopted. The foil automatic changing machine is outside the magnetism yoke and 12 pieces foil can be changed in one time. The design and fabrication of the probe system has been finished and it is going to the progress of installation and adjusting. The experimental verification on probe rod driving and foil changing system has been finished in 2010. The whole stripping extraction system will be installed in 2013.

THPFI027

STUDY ON STRUCTURE AND THERMAL ANALYSIS OF CSNS R BEAM DUMP

shielding, neutron, proton, target

3356

L. Liu, L. Kang, X.J. Nie, H. Qu
IHEP, Beijing, People's Republic of China

The China Spallation Neutron Source (CSNS) accelerator systems will provide a 1.6 Gev proton beam to a target for neutron production. Beam dump system is an important part of CSNS, and it is used to incept the waste beam. The beam dump system is composed with vacuum part and shielding part. For the design of shielding part, the material is steel at the centre and concrete outside, we must control the temperature of steel and concrete not too high, and it will be a serious problem that the concrete crazes because of the high temperature. So the thermal analyses must be done to ensure safety. Taking CSNS R dump for example, we use software to make model and analyze the thermal, then optimizing the result. According to the result, we control the work time and dimension of the beam to control the temperature of the iron and concrete. This article expatiate the study on the structure design and thermal analyses.

THPFI042

Design Considerations for Phase Reference Distribution System at ESS

linac, LLRF, cavity, radiation

3379

R. Zeng
ESS, Lund, Sweden
A.J. Johansson
Lund University, Lund, Sweden

PRDS (Phase Reference Distribution System) will be serving as the phase alignment line for all cavities with high phase stability. With the current design of individually RF source powering for most cavities at ESS, phase reference distribution system should provide the reference signals for totally 34 LLRF systems at 100 meters long low-frequency section (for all 352.21MHz cavities, including RFQ, DTL, bunching cavities and spokes), and for totally 180 LLRF systems at 342 meters long high-frequency section (for all 704.42MHz cavities, including medium beta and high beta elliptical cavities). Coaxial cable based solution and optical fibre based solution are discussed in this note for PRDS (Phase reference distribution system) at ESS. Some possible schemes in each of these two distribution solutions are introduced and comparisons among these schemes are made. Some effort is made as well to find out a reasonable design for PRDS at ESS.

THPFI045

Reliability Approach for Machine Protection Design in Particle Accelerators

linac, proton, beam-losses, booster

3388

A. Apollonio, J.-B. Lallement, B. Mikulec, B. Puccio, J.L. Sanchez Alvarez, R. Schmidt, S. Wagner
CERN, Geneva, Switzerland

Particle accelerators require Machine Protection Systems (MPS) to prevent beam induced damage of equipment in case of failures. This becomes increasingly important for proton colliders with large energy stored in the beam such as LHC, for high power accelerators with a beam power of up to 10 MW, such as the European Spallation Source (ESS), and for linear colliders with high beam power and very small beam size. The reliability of Machine Protection Systems is crucial for safe machine operation; all possible sources of risk need to be taken into account in the early design stage. This paper presents a systematic approach to classify failures and to assess the associated risk, and discusses the impact of such considerations on the design of Machine Protection Systems. The application of this approach will be illustrated using the new design of the MPS for LINAC 4, a linear accelerator under construction at CERN.

THPFI050

Some Ideas Towards Energy Optimization at CERN

vacuum, proton, radiation, secondary-beams

3400

H.J. Burckhart, J.-P. Burnet, F. Caspers, V. Doré, L. Gatignon, C. Martel, M. Nonis, D. Tommasini
CERN, Geneva, Switzerland

The paper presents the efforts of CERN to optimize its energy usage. Work is proceeding in 3 areas: accelerators, campus and infrastructure, and re-use of thermal “waste” energy. The accelerator chain has the potential to further reduce the energy consumption by dynamic suppression of cycles when they are temporarily not needed and by operating magnets in pulsed mode. R&D for future accelerators includes the recuperation of the RF energy, which is not used for acceleration of the beams. Concerning the CERN campus more than half of the buildings are older than 40 years. Hence there is a big need for renovation, which includes energy aspects. New buildings use renewable energy whenever possible. As an example a building is under construction, which will use a 250 m2 solar field together with an absorption refrigerator for cooling purposes. Finally, about 80% of the electric energy gets dissipated in air cooling towers. Part of this energy can be re-used for heating buildings.

THPFI061

Design Process of the Interlock Systems for the Compact Linear Collider

collider, target, linear-collider, hadron

3433

P. Nouvel, M. Jonker, B. Puccio
CERN, Geneva, Switzerland
H. Tap
INPT, Toulouse, France

Interlock systems are a critical part for the machine protection of linear colliders. Their goal is to inhibit the next pulse either on failure of critical equipment and/or on low beam quality evaluation. This paper presents the on-going process to validate design choices for the Compact Linear Collider (CLIC) interlock systems. The design process starts by establishing requirements. In mission-critical system case, they are mainly focused on the dependability. Moreover, the new concept of fast beam quality analysis has been introduced into the CLIC interlock system and will be discussed in this paper. To support the design process, experimentation on this concept has been launched. In addition, a hardware demonstration of the interlock systems has been set-up. It allows validating the design in concordance with the requirements.

THPFI063

Development and Beam Tests of an Automatic Algorithm for Alignment of LHC Collimators with Embedded BPMs

alignment, pick-up, collimation, insertion

3439

G. Valentino
University of Malta, Information and Communication Technology, Msida, Malta
R.W. Aßmann
DESY, Hamburg, Germany
R. Bruce, M. Gasior, D. Mirarchi, A.A. Nosych, S. Redaelli, B. Salvachua, N.J. Sammut
CERN, Geneva, Switzerland

Collimators with embedded Beam Position Monitor (BPM) buttons will be installed in the LHC during the upcoming long shutdown period. During the subsequent operation, the BPMs will allow the collimator jaws to be kept centered around the beam trajectory. In this manner, the best possible beam cleaning efficiency and machine protection can be provided at unprecedented higher beam energies and intensities. A collimator alignment algorithm is proposed to center the jaws automatically around the beam. The algorithm is based on successive approximation, as the BPM measurements are affected by non-linearities, which vary with the distance between opposite buttons, as well as the difference between the beam and the jaw centers. The successful test results, as well as some considerations for eventual operation in the LHC are also presented.

THPFI066

Performance Enhancement of Electrical Power System at NSRRC

radio-frequency, synchrotron, power-supply, synchrotron-radiation

3448

T.-S. Ueng, J.-C. Chang, Y.F. Chiu, K.C. Kuo, Y.-C. Lin
NSRRC, Hsinchu, Taiwan

A lot of efforts have been devoted to improve the reliability, the stability and the power quality of NSRRC electrical power system in recent years. These improvements include the power factor correction, solving nuisance tripping of air circuit breakers, replacing old-type capacitor banks, installing automatic voltage regulators and designing multi-source backup system with automatic transfer switch. All these improvement works are to ensure the reliable operation of NSRRC power system and reduce the electrical power accidents during the normal operation. Further, it can also provide the convenience for the electric power dispatching of NSRRC during the regular maintenance of power system.

THPFI068

Status of the Utility System Construction for the 3 GeV TPS Storage Ring

storage-ring, booster, status, synchrotron

3454

J.-C. Chang, W.S. Chan, J.-R. Chen, Y.F. Chiu, Y.-C. Chung, C.W. Hsu, K.C. Kuo, Y.-C. Lin, C.Y. Liu, Y.-H. Liu, Z.-D. Tsai, T.-S. Ueng
NSRRC, Hsinchu, Taiwan

The construction of the utility system for the 3.0 GeV Taiwan Photon Source (TPS) was started in the end of 2009. The utility building for the TPS ring has been completed in the end of 2012. Main utility equipment has been installed inside. The whole construction of the utility system is scheduled to be completed in the mid of 2013. Total budget of this construction is about four million dollars. This utility system presented in this paper includes the electrical power, cooling water, air conditioning, compressed air and fire control systems.

THPFI069

Power Saving Status in the NSRRC

synchrotron, synchrotron-radiation, status, radiation

3457

J.-C. Chang, Y.F. Chiu, Y.-C. Chung, C.W. Hsu, Y.-C. Lin, C.Y. Liu, Z.-D. Tsai, T.-S. Ueng
NSRRC, Hsinchu, Taiwan

National Synchrotron Radiation Research Center (NSRRC), Taiwan will complete the construction of the civil and utility system engineering of the Taiwan Photon Source (TPS) in the mid of 2013. The power consumption of the TPS is estimated about 2.3 times of that of the existing Taiwan Light Source (TLS). To cope with increasing power requirement in the near future, we have been conducting several power saving schemes, which include power requirement control, optimization of chillers operation, air conditioning system improvement, power factor improvement, application of heat pump, and publishing monthly power saving report. We will also connect the main pipes of TLS and TPS chilled water systems to obtain more efficient operation in 2013.

THPFI070

Event Based System to Manage the Maintenance of Taiwan Photon Source

status, photon, PLC, synchrotron

3460

C.W. Hsu, C.S. Chen, C.Y. Liu, Z.-D. Tsai
NSRRC, Hsinchu, Taiwan

This paper presents a model of event based maintenance management system to provide commission condition of utility facility. The system adopts cloud servers with structured query language (SQL) database to deal with all utility facility information. The system collects all event condition, including scheduled maintenance, troubleshooting, alert information and equipment specifications. The user can easily access all the facility information in mobile devices by scanning the quick response (QR) tag. The system can increase system reliability, decrease maintenance cost, minimize not programmed shutdowns and enhance system performance. Besides, the system can also provide enough information to schedule maintenance order by user or preventive and optimize energy usage.

THPFI071

Baking Tests and Results of A1050 Diamond Edge Gasket

vacuum, target, power-supply, ion

3463

Y.T. Huang, C.-C. Chang, J.-R. Chen, G.-Y. Hsiung, S-N. Hsu, H.P. Hsueh
NSRRC, Hsinchu, Taiwan
J.-R. Chen
National Tsing Hua University, Hsinchu, Taiwan

A1050 is a common and soft material, widely used in everyday life. It is machinable and cheap, which makes it a candidate for a gasket material. In the case of sealing between disparate materials, treating the thermal expansion when the gasket suffers from baking is difficult. The clearance and the eccentricity between the gasket and the flange are also important; most leaks occur about 80 ~ 110 oC. The experimental apparatus comprised a vacuum chamber with six diamond-edge gaskets assembled, a turbo-molecular pump and an extractor gauge. The pre-baking torque for this gasket is 70 – 80 kg cm; the rates of both heating and cooling are less than 40 oC per hour. The gaskets are baked repeatedly under the same conditions excluding the target temperature set for baking. A1050 diamond gaskets work well after baking at 120 ~ 140 oC; at temperature 170 ~ 180 oC, leaks sometimes appear on cooling. This paper presents the baking results of A1050 diamond-edge gasket and explains the cause of leaking after baking above 150 oC.

THPFI075

Baking Test for an In-vacuum Undulator

vacuum, undulator, synchrotron, synchrotron-radiation

3469

L.H. Wu, C.K. Chan, J.-R. Chen, G.-Y. Hsiung, S-N. Hsu, H.P. Hsueh, J.C. Huang, C.K. Yang
NSRRC, Hsinchu, Taiwan
J.-R. Chen
National Tsing Hua University, Hsinchu, Taiwan

For Taiwan Photon Source in NSRRC, the in-vacuum undulator (IU22) will be set in the straight section. The baking test took place in the NSRRC. The heating wires were welded on the outside wall of stainless chamber. The tape heaters were used for the sites without the heating wires. After acceptation test, we assemble the residual gas analysis (RGA) and extractor gauge in the IU22. The pumping down curve and RGA spectrum were recorded and investigated. It was found the slope of the pumping curve near 1 h is -0.99. When the temperature gradually increases to about 185 oC, the vacuum pressure arrives to about 8.7x10^-5 Torr. The most gas source is from water before baking process. After baking test, the major residual gas includes H2, CH4, H2O, CO, and CO2. We analyze the RGA spectrum during the baking process and discuss in the paper.

THPFI078

Design and Experiment on Auto-alignment Control System of Taiwan Photon Source

alignment, laser, storage-ring, feedback

3475

M.H. Wu, J.-R. Chen, M.L. Chen, P.S.D. Chuang, H.C. Ho, K.H. Hsu, D.-G. Huang, W.Y. Lai, C.-S. Lin, C.J. Lin, H.C. Lin, H.M. Luo, S.Y. Perng, P.L. Sung, T.C. Tseng, H.S. Wang
NSRRC, Hsinchu, Taiwan
J.-R. Chen
National Tsing Hua University, Hsinchu, Taiwan

TPS (Taiwan Photon Source) is a new 3-GeV synchrotron ring to be constructed at the NSRRC (National Synchrotron Radiation Research Center), Taiwan. There were hundreds of magnets that must be aligned on the absolute position to keep the electronic beam in the desire path while orbiting. Due to the problems of manpower, set up time, accuracy of adjustment, deformation of the floor, limited workspace and frequent earthquakes in Taiwan, an auto-alignment girder control system was designed to meet this requirement. The design and experiment of the auto-alignment system were tested successfully in the laboratory at NSRRC. The experiment of the auto-alignment control system would be implemented with half of the ring girders in the TPS. The detailed alignment design and status will be discussed in this paper.

THPME019

Design of the Cold Mass Support Assembly of Test Cryomodule for IMP ADS-Injector II

solenoid, cavity, cryomodule, vacuum

3543

Y. Liu, S. Sun, J. Wang, L. Wang, S.Y. Wang
SINAP, Shanghai, People's Republic of China
X.L. Guo
JiangShu University, Jiangsu Province, People's Republic of China

In order to test the performance of the HWR cavities and verify the related technique for cooling of the cavities and the solenoids together, a test cryomodule (TCM1) containing one superconducting HWR cavity followed by one cold BPM and two superconducting solenoids was developed for the Injector II of the Accelerator Driven Sub-critical System (ADS). The TCM1 consists of the cryostat and the cold mass assembly. The cryostat is composed of vacuum chamber, thermal shields, cooling circuit, cold mass support assembly, and instrumentation. A set of cold mass support assembly was developed for supporting the cold mass working at 4.4 K. The support assembly mainly consists of Ti support frame, stainless steel rods, adjustable mechanisms and LHe cooling passage. It can not only support the weight of the cold mass but also stand the thermal stress during the cool down. In order not to affect the performance of the cavity, it will not impose any force on the HWR cavity. It can be adjustable for alignment of the cold mass both at room temperature and 4.4 K. This paper provides the detailed design of the TCM1 cold mass support assembly.

THPME021

Application of Magnetic Field Integral Measurement of Magnet Module to Research Alterable Gap Undulator

multipole, undulator, quadrupole, synchrotron

3549

H.F. Wang, W. Zhang, Q.G. Zhou
SINAP, Shanghai, People's Republic of China

A set of magnetic measurement system and a suitable magnetic field optimization method for an In-Vacuum Undulator (IVU) with alterable gaps have been developed. The method is based on assembling orders and directions of all magnet modules for correcting rms optical phase error, electron trajectory and multipole components of the IVU. Magnetic field distributions on axis and off axis of every magnet block module are measured. Then the appropriate magnetic block modules will be chosen from measured magnet modules according to a sorting algorithm and assemble them to two inner girders of an IVU. This paper will describe a magnetic field measurement system, magnetic field optimization method and optimized results of an IVU with a period of 20 mm.

THPME023

A NEW HARMONIC COIL BENCH AT SINAP FOR THE ALS COMBINED FUNCTION SEXTUPOLE MAGNETS

multipole, dipole, sextupole, quadrupole

3552

J.D. Zhang, H.W. Du, L. Yin, Q.G. Zhou
SINAP, Shanghai, People's Republic of China
N. Li, A. Madur
LBNL, Berkeley, California, USA

A new harmonic coil bench has been developed at Shanghai Institute of Applied Physics (SINAP) to measure the ALS combined function sextupole magnets. The measurement system has been designed with the aim to perform precise, fast and reliable measurements of series of magnets. It determines the strength, and the multipole content of the field as well as the magnetic axis for precise positioning of alignment targets on top of the multipoles. The multipole, while supported on a marble platform, can be moved with regard to the rotating coil using multi-dimensional adjustment plate. The resolution of the movement is read out by micrometer with a few μm resolutions. This article introduces the measurement system constitutes.

THPME026

First Results of the PAL-XFEL Prototype Undulator Measurements

undulator, FEL, radiation, insertion-device

3561

D.E. Kim, H.S. Han, Y.-G. Jung, H.-G. Lee, S.B. Lee, W.W. Lee, K.-H. Park, H.S. Suh
PAL, Pohang, Kyungbuk, Republic of Korea
M.-H. Cho, I.S. Ko
POSTECH, Pohang, Kyungbuk, Republic of Korea

Pohang Accelerator Laboratory (PAL) is developing 10 GeV, 0.1 nm SASE based FEL for high power, short pulse X-ray coherent photon sources named PAL-XFEL. At the first stage PAL-XFEL needs two undulator lines for photon source. PAL is developing undulator magnetic structure based on EU-XFEL design. The hard X-ray undulator features 7.2 mm min magnetic gap, and 5.0 m magnetic length with maximum effective magnetic field larger than 0.908 T to achieve 0.1nm radiation at 10 GeV electron energy. A prototype for PAL-XFEL Xray undulator line is completed and the measurement, correction results are summarized.

THPME027

Design and Fabrication of Prototype Phase Shifter for PAL XFEL

undulator, FEL, electron, radiation

3564

H.-G. Lee, Y.-G. Jung, H.-S. Kang, D.E. Kim, S.B. Lee, W.W. Lee, K.-H. Park, H.S. Suh
PAL, Pohang, Kyungbuk, Republic of Korea

Pohang Accelerator Laboratory(PAL) is developing a SASE X-ray Free Electron Laser based on 10 GeV linear accelerator. Prototype phase shifters are being developed to be used for the X-ray and Soft X-ray undulator line. The phase shifters will be used to adjust the phase of the electron beam with respect to that of the radiation field. Two prototype phase shifters are being developed. One is based on the EU-XFEL phase shifter using zero-potential iron yoke, and the other one is similar to FERMI phase shifter where only permanent magnets are used. Driving system consists of 5 phase stepping motor, left/right handed ball screw and absolute linear encoder. In this paper, we describe the design, fabrication and test results of the two phase shifter prototypes.

THPME034

The LHC Cryogenic Operation Availability Results from the First Physics Run of Three Years

cryogenics, instrumentation, monitoring, collider

3585

D. Delikaris, K. Brodzinski, S.D. Claudet, G. Ferlin, L.J. Tavian, U. Wagner
CERN, Geneva, Switzerland

The LHC (Large Hadron Collider) accelerator consists in eight cryogenically independent sectors, each 3.3 km long with a cold mass of 4500 ton cooled at 1.9 K. Each helium cryogenic plant combines an 18 kW at 4.5 K refrigerator and a 2.4 kW at 1.8 K refrigeration unit. Since early operation for physics in November 2009, the availability has been above 90% for more than 260 days per year, ending at 94.8% in 2012 and corresponding to an equivalent availability of more than 99% per independent sector. The operation and support methodology as well as the achieved performance results are presented. Emphasis is given on implementing operational return for short, medium and long term consolidations. Perspective for restart after the first long shutdown of the LHC works will be described.

THPME035

The Electronic System Design and Realization for First Set 500 MHz KEKB SRF Module High Power Test

SRF, cavity, cryogenics, HOM

3588

F.-T. Chung, L.-H. Chang, M.H. Chang, L.J. Chen, M.-C. Lin, Y.-H. Lin, Z.L. Liu, C.H. Lo, M.H. Tsai, Ch. Wang, T.-T. Yang, M.-S. Yeh, T.-C. Yu
NSRRC, Hsinchu, Taiwan

This article reports the home-made electronics circuits for reading the various electronics signals which can be used for site acceptance of superconducting resonant cavity. The adjustment of parameters during 1st SRF high power acceptance can also be used for the update of the 2nd electronics. The modular electronics system will provide the advantages of fast repair, preparing spare parts easily, short install time and flexible adjustment. The hardware whole electronics system is mainly designed by CPLD, PLC and Display meters. The Military Standard connectors are used for signals connection. There are always junction boxes for signal transmission test and convenient signal jumping for ensuring the correct signal source. In safety action, there are Fast Interlock Sum (0-10us) and slow ready chain (50ms-150ms). The complete system realizes the real time monitor and protection of superconducting resonant cavity.

THPME039

The Control System for the Purification Station at NSRRC

cryogenics, monitoring, vacuum, synchrotron

3597

T.F. Lin, S.-H. Chang, W.-S. Chiou, F. Z. Hsiao, C.K. Kuan, H.C. Li, C.P. Liu, H.H. Tsai
NSRRC, Hsinchu, Taiwan

A cryogenic adsorber was used liquid nitrogen to trap the impurities from gaseous helium in the helium cryogenic system. NSRRC parallel connected five cryogenic adsorbers for the cryogenic system in the year 2011; five additional cryogenic adsorbers will be installed in the year 2013. The original design of liquid nitrogen filling was motored and controlled manually to keep the efficiency of the purifying. The regeneration of the cryogenic adsorber must be performed manually as well by using heater and vacuum pump after saturated of the cryogenic adsorber. NSRRC develop one control system that is allowed the liquid nitrogen filling and regeneration process turns into automatically. This paper is aimed to present the construction of the control system. The installation and test results will be included in this paper as well.

THPME040

The Installation and Commissioning of the Helium Cryogenic System for theTPS Project

cryogenics, SRF, storage-ring, electron

3600

H.H. Tsai, S.-H. Chang, W.-S. Chiou, F. Z. Hsiao, C.K. Kuan, H.C. Li, T.F. Lin, C.P. Liu
NSRRC, Hsinchu, Taiwan

The construction of an electron accelerator with energy 3 GeV is under way for high brilliance and flux X-ray photon source at NSRRC. There will be eventually four superconducting radio frequency (SRF) cavities installed to maintain the electron energy. The helium cryogenic system has been designed and fabricated to provide the required liquid helium for SRF cavities. The cryogenic system consists of the 700-W refrigerator, the 315-kW variant frequency compressor, the oil removal system, the recovery compressor system, the gas helium buffer tanks, and one 7000-L liquid helium Dewar. The overall system installation and commissioning will be presented and discussed in this paper.

THPME045

TEST RESULTS OF A NB3SN QUADRUPOLE COIL IMPREGNATED WITH RADIATION-RESISTANT MATRIMID 5292

quadrupole, dipole, radiation, collider

3612

A.V. Zlobin, G. Ambrosio, N. Andreev, E.Z. Barzi, R. Bossert, G. Chlachidze, V.V. Kashikhin, S. Krave, A. Nobrega, I. Novitski
Fermilab, Batavia, USA

Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy.
FNAL is developing advanced Nb3Sn magnets for present and future accelerators. Insulation is one of the primary elements of magnet design, essential for maintaining its electrical, mechanical and thermal performance. The Nb3Sn magnet fabrication process involves coil reaction at high temperature and then impregnation with epoxy to restore the insulation electrical and mechanical properties. The traditional epoxy offers adequate structural and electrical properties, but has a low radiation strength which limits the lifetime of accelerator magnets operating in severe radiation environments. Studies to replace epoxy as impregnation material for Nb3Sn coils with high radiation-resistant material have started at FNAL ten years ago. The studies concentrated on the Matrimid® 5292, a bismaleimide based material, which has appropriate viscosity and potlife as well as provides excellent mechanical, electrical and thermal coil properties. A 1 m long Nb3Sn quadrupole coil was recently fabricated, impregnated with Matrimid and tested in a quadrupole magnetic mirror at 4.2 and 1.9 K. Coil test results are presented and compared to the results for similar coils impregnated with epoxy.

THPME046

A Summary of the Quality of the ALS Combined Function Sextupole Magnets

sextupole, dipole, multipole, quadrupole

3615

N. Li, A. Madur
LBNL, Berkeley, California, USA
C. Chen, H.J. Hu, J. Jin, Y.M. Wen, L. Yin, J.D. Zhang, Q.G. Zhou
SINAP, Shanghai, People's Republic of China

Funding: This work was supported by the Office of Science, U.S. Department of Energy under DOE contract number DE-AC02-05CH11231.
A total of 51 combined function magnets is required to upgrade the Advanced Light Source (ALS) Storage Ring at LBNL. These magnets will provide 4 types of magnetic fields: sextupole, horizontal and vertical dipoles, and skew quadrupole and will enable an emittance reduction and upgrade of the beam quality in the ALS ring. A relatively new procedure using EDM cut poles after core assembly that was first used by Buckley System Ltd, NZ was adopted during the production of these magnets. Also, a new 3D CAD modeling was used for the coil design. A total of 57 magnets (including prototypes and spare magnets) were built by the Shanghai Institute of Applied Physics (SINAP) in China. These magnets have achieved extraordinarily high pole profile accuracies and exhibit excellent coil performance characteristics: resistances and water flows reached a high degree of consistency. Consequently, the system errors of the magnetic field of these magnets all meet the LBNL specifications. This paper will summarize the mechanical quality and magnetic field properties of these magnets. The interrelationship between the qualities of coil and the magnet field will be described as well.

THPME048

Assembly and Test of a Modified Spectrometer Solenoid for MICE

solenoid, radiation, target, coupling

3621

S.P. Virostek, D. Li, P. Pan, S. Prestemon
LBNL, Berkeley, California, USA
R. Preece
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom

Funding: This work is supported by the Office of Science, US-DOE under DOE contract DE-AC02-05CH11231.
The MICE superconducting spectrometer solenoids have been modified and rebuilt as a result of the testing done in 2008, 2009 and 2010. The number of two-stage cryocoolers was increased from three in 2009 to five in the modified magnet. The new shield for the spectrometer solenoid is fabricated primarily from 1100-O aluminum instead of 6061-T6 aluminum used in the former versions of the magnet. The thermal connection between the shield and the first-stage of the cold heads has been improved to reduce the temperature drop between the shield and the coolers. As a result of these changes, the first-stage temperatures for the coolers are below 45K, which resulted in an increase in the refrigeration generated by the cooler second stages. The quench protection system has been altered in order to provide additional protection to the magnet in the event of a lead failure between the magnet power supply and the magnet coils. The quality of the shield and cold mass MLI wrap has also been improved. Details of the modifications and test results demonstrating improved magnet performance are presented in this paper.

THPWA003

Novel Crate Standard MTCA.4 for Industry and Research

LLRF, monitoring, radio-frequency, free-electron-laser

3633

T. Walter, F. Ludwig, K. Rehlich, H. Schlarb
DESY, Hamburg, Germany

Funding: This project is funded by the Helmholtz Association (Helmholtz Validation Fund HVF-0016).
MTCA.4 is a novel electronic standard derived from the Telecommunication Computing Architecture (TCA) and championed by the xTCA for physics group, a network of physics research institutes and electronics manufacturers. MTCA.4 was released as an official standard by the PCI Industrial Manufacturers Group (PICMG) in 2011. Although the standard is originally physics-driven, it holds promise for applications in many other fields with equally challenging requirements. With substantial funding from the Helmholtz Association for a two-year validation project, DESY currently develops novel, fully MTCA.4-compliant components to lower the barriers to adoption in a wide range of industrial and research use scenarios. Core activities of the project are: refinement, test and qualification of existing components; market research, market education (web information services, workshops); coordinated development of missing MTCA.4 components; further advancement of the standard beyond the current PICMG specification; investigation of measures to counteract electro-magnetic interferences and incompatibilities; training, support and consultancy. This paper summarizes intermediate results and lessons learned at project half-time.

THPWA005

The HIT Accelerator as Part of a Medical Product: Impacts on the Maintenance Strategy

ion, ion-source, proton, linac

3639

A. Peters, R. Cee, Th. Haberer, T. Winkelmann
HIT, Heidelberg, Germany

The HIT accelerator produces protons and carbon beams with a large variety of parameters: 255 different energies, four foci and ten intensity steps per ion are independently available at 5 iso-centres to be requested by the dose delivery system for tumor treatment. Thus the whole accelerator chain is part of a medical product, in case of HIT an in-house manufactured device. The overall risk and quality management has deep influences on the maintenance process. Not only the huge volume of necessary documentation reflects this impact but also the organizational process before, along and after the services at HIT. Especially, the comprehensive testing after the maintenance procedures follows sophisticated checklists (e.g. the ion source service). On the other hand, a high operational availability of the accelerator in a hospital is mandatory. To realize 8250 hours of accelerator uptime per year in case of HIT, a maintenance strategy is necessary, which interleaves the regular service of the building infrastructure, e.g. air conditioning, with the periodic maintenance of the accelerator components. In detail, this approach will be discussed along the magnets and the gantry structure.

THPWA023

Research on Modeling of the High-density Current Electron Gun System Based on T-S Fuzzy Model

electron, gun, simulation, cathode

3678

B. Lv, D.M. Li, H.J. Su
SINAP, Shanghai, People's Republic of China

Abstract: The stability of the electron beam is considered as an important performance of industrial electron accelerators. For the beam control system of the accelerator, it is significant to obtain the accurate model of the electron gun system. The paper presents a fuzzy modeling method based on the Takagi-Sugeno (T-S) fuzzy model. A T-S model can be obtained using the system identification algorithms from input-output data. In our approach, fuzzy c-means (FCM) clustering algorithm is applied to identify the model structure. And a hybrid method based on quantum-inspired differential evolution algorithm (QDE) and genetic algorithm (GA) is proposed to learn the parameters of T-S fuzzy model. Experiments on the Box-Jenkins gas furnace data have verified the validity of the modeling approach. The simulation results show that the T-S fuzzy model is very well to describe the electron gun system and reveal its performance.

THPWA029

Transient Ionizing Radiation Effect of Bipolar Operational Amplifiers to Pulsed X-rays

radiation, electron, feedback, injection

3687

X.M. Jin
Xiaoming Jin, People's Republic of China
X.Y. Bai, R.B. Li, D.S. Lin, Q. Ma, C. Qi, G.Z. Wang, S.C. Yang
NINT, Xi'an, People's Republic of China

Abstract – The pulsed ionizing radiation effect of monolithic operational amplifiers is investigated using a flash X-ray facility. The experimental results show that the pulsed ionizing radiation produces voltage surges in the devices and the output voltage recovers linearly after transient disturbance which includes a negative peak and a positive peak. The recovery time depends on the amplitude of the positive peak and the inherent slew rate of the devices. The degradation of transient disturbance amplitude and the recovery time versus ionizing dose rate of pulsed X-rays is researched. The relationship of circuit effects to physical mechanisms is investigated in detail. The photocurrent induced by transient ionizing radiation in the PN junctions in integrated circuits is responsible for the electrical degradation. Keywords – Transient ionizing Radiation effect, Transient disturbance, Photocurrent, integrated circuits

THPWA033

Material Discrimination Technology for Cargo Inspection with Pulse-to-pulse Linear Electron Accelerator

radiation, electron, collimation, target

3699

S. Ogorodnikov, R. Apevalov, M. Arlychev, I. Polevchenko, A. Rodionov, I.E. Shevelev
Scantronic Systems, St. Petersburg, Russia

In the present article a complex of technological solutions based on 6/3.5 MeV pulse-to-pulse linear accelerator, detectors made of CWO scintillators coupled with PIN photodiodes and image processing algorithms proposed. Energies, dose rate and other parameters of accelerator were optimized to reach high performance of the x-ray system and to carry out robust and reliable material discrimination in the mass thickness range up to 120 g/cm² at least. Evaluation of effective atomic number of materials of main three groups (organics, mineral/light metals, metals) was fulfilled with preciseness ±1 for the optimal mass thickness range at the scanning speed 60 cm/s. Instrument for evaluation of physical mass of the separate objects on the image is proposed and realized.

THPWA035

Intervention Management from Operation to Shutdown

radiation, feedback, site, cryogenics

3705

C. Garino, B. Daudin, J. De Jonghe, A. Dorsival, F. B. Dos Santos Pedrosa, G. Dumont, K. Foraz, E.R.F. Reguero Fuentes
CERN, Geneva, Switzerland

The Intervention Management Planning and Coordination Tool (IMPACT) is now widely used in all the accelerator complex and beyond. This unique repository improves the availability of the intervention information for all facilities, and enhances its traceability. It supports a standardized approval workflow and direct link to the access system for improved control and productivity. IMPACT currently has 1418 active users who have defined 6880 intervention requests in 2012 so far. In 2013, the CERN Accelerator complex will enter a shutdown mode after a long period of operation. Careful preparation and scheduling of activities is paramount in order to keep the shutdown as short as possible, whilst guaranteeing safety. During execution, strict control of access will be enforced considering the radiation levels. This paper will summarize the main improvements to IMPACT in this context: work dose planning with respect to ALARA principles including integration with the operational dosimetry system and automatic generation of safety documents from intervention data.

THPWA047

GEM*STAR - New Nuclear Technology to Produce Inexpensive Diesel Fuel from Natural Gas and Carbon

neutron, linac, proton, target

3738

R.P. Johnson, F. Marhauser
Muons. Inc., USA
C. Bowman, R.B. Vogelaar
ADNA, Los Alamos, New Mexico, USA

The 75,000 tons of US stored spent nuclear fuel (SNF) from conventional nuclear reactors is a resource that could provide 125 years of all US electrical power. Or it could also provide a great amount of process heat for many applications like producing green diesel fuel from natural gas and renewable carbon. An accelerator system like the SNS at ORNL can provide neutrons to convert SNF into fissile isotopes to provide high temperature heat using technology developed at the ORNL Molten Salt Reactor Experiment. In the GEM*STAR accelerator-driven subcritical reactor that we wish to build, the accelerator allows subcritical operation (no Chernobyls), the molten salt fuel allows volatiles to be continuously removed (no Fukushimas), and the SNF does not need to be enriched or reprocessed (to minimize weapons proliferation concerns). The molten salt fuel and the relaxed availability requirements of process heat applications imply that the required accelerator technology is available now. A new opportunity has arisen to use GEM*STAR to reduce the world’s inventory of weapons-grade plutonium leaving only remnants that are permanently unusable for nuclear weapons.
* Charles D. Bowman et al., “GEM*STAR: The Alternative Reactor Technology Comprising Graphite, Molten Salt, and Accelerators,” Handbook of Nuclear Engineering, Springer (2010).

THPWO002

Progress of Construction and Installation of the SPIRAL2 Accelerator

ion, linac, rfq, vacuum

3755

R. Ferdinand, P. Bertrand, X. Hulin, M. Jacquemet, E. Petit
GANIL, Caen, France

Officially approved in May 2005, the SPIRAL2 project was launched in July 2005 at GANIL, with the active participation of French laboratories (CEA, CNRS) and international partners. This new facility is composed of a linear accelerator producing deuteron, proton and heavy ion beams in a wide range of energies and intensities, with two dedicated experimental areas in the fields of Neutron for Science (NFS) and very heavy and super heavy element production (S3). In a second step, the facility will also produce Rare elements serving a low energy RIB experimental hall, or post-accelerated by means of the existing cyclotron CIME. This paper presents the performances of the main accelerator components, and the installation process into the SPIRAL2 building.

THPWO068

Resonance Frequency Control Characteristics of the 100-MeV Drift Tube Linac

DTL, resonance, proton, linac

3912

H.-J. Kwon, Y.-S. Cho, J.-H. Jang, H.S. Kim, K.T. Seol, Y.-G. Song
KAERI, Daejon, Republic of Korea

Funding: This work was supported by the Ministry of Science and Technology of the Korean Government.
A 100-MeV, 20mA proton accelerator has been developed by KAERI (Korea Atomic Energy Institute). Total 11 DTL (Drift Tube Linac) tanks are used to accelerator the proton beam from 3-MeV to 100-MeV. A RCCS (Resonance frequency Control Cooling System) has been developed to control the resonance frequency of each DTL tank. The coolant for the drift tube and quadrupole magnets are supplied by the RCCS, whereas the wall coolant temperature maintains constant at 27 degree C by using the DI water supplied from the utility. In this paper, the resonance frequency control schemes are summarized and the control characteristics of the DTL tank by using the RCCS are discussed.