IPAC2013 - List of Keywords (synchrotron)

Paper	Title	Other Keywords	Page
MOODB101	Manufacturing of the First of Series SIS100 Dipole Magnet	dipole, instrumentation, magnet-design, laser	31
	St. Sattler, W. Gärtner, Dr. Scheller, R. Schönbein, W. Walter BNG, Würzburg, Germany E.S. Fischer, J.P. Meier, H. Müller, P. Schnizer GSI, Darmstadt, Germany
	Babcock Noell (Würzburg, Germany) manufactures the First of Series (FOS) SIS100 dipole magnet for the FAIR project. This contribution reports on the progress during the design-phase, performed together with GSI, and on the manufacturing- and assembly-processes. Special emphasis will be given on new or special techniques adopted to fulfill the stringent requirements demanded by such a magnet. The new tooling systems and machines which were developed and brought into operation for this FOS magnet will be discussed.

MOODB103	Results of an Experiment on Hydrodynamic Tunnelling at the SPS HiRadMat High Intensity Proton Facility	target, simulation, proton, instrumentation	37
	R. Schmidt, J. Blanco, F. Burkart, D. Grenier, D. Wollmann CERN, Geneva, Switzerland E. Griesmayer CIVIDEC Instrumentation, Wien, Austria N.A. Tahir GSI, Darmstadt, Germany
	To predict the damage for a catastrophic failure of the protections systems for the LHC when operating with beams storing 362 MJ, simulation studies of the impact of an LHC beam on targets were performed. Firstly, the energy deposition of the first bunches in a target with FLUKA is calculated. The effect of the energy deposition on the target is then calculated with a hydrodynamic code, BIG2. The impact of only a few bunches leads to a change of target density. The calculations are done iteratively in several steps and show that such beam can tunnel up to 30-35 m into a target. Validation experiments for these calculations at LHC are not possible, therefore experiments were suggested for the CERN Super Proton Synchrotron (SPS), since simulation studies with the tools used for the LHC also predict hydrodynamic tunnelling for SPS beams. An experiment at the SPS-HiRadMat facility (High-Radiation to Materials) using the 440 GeV beam with 144 bunches was performed in July 2012. In this paper we compare the results of this experiment with our calculations of hydrodynamic tunnelling.
	Slides MOODB103 [40.426 MB]

MOPEA001	Status of the Australian Synchrotron Top-Up Operations	injection, storage-ring, linac, diagnostics	58
	M.J. Boland, R.T. Dowd, G. LeBlanc, D.C. McGilvery, D. Morris, Y.E. Tan, J. Trewhella, D. Zhu, E.D. van Garderen ASCo, Clayton, Victoria, Australia
	In May 2012 the Australian Synchrotron commenced Top-Up Operations for User beamtime. The facility was designed for top-up from the start with a full energy 3 GeV injection system, however top-up only became a priority once the beamline user community had established itself at the new facility in operation since April 2007. New beam diagnostic and equipment protections systems were implemented as part of the move to top-up, including a new injection efficiency monitoring system. The effect of top-up on the beamline data was also tested with each beamline prior to engaging top-up during user runs. Top-up has now been running successfully for one year and the performance statistics from this period will be presented. Top-up operations is a very popular standard mode for user beam and falling into decay mode is now treated almost as a beam dump.

MOPEA002	1.5 GeV Low Energy Mode for the Australian Synchrotron	storage-ring, booster, extraction, injection	61
	R. Clarken, M.J. Boland, Y.E. Tan ASCo, Clayton, Victoria, Australia J.S. Hughes, K.P. Wootton The University of Melbourne, Melbourne, Australia
	The Australian Synchrotron injection system and storage ring have been retuned to 1.5 GeV for use in special operations and machine development modes. The systems were designed for 3 GeV user operations but for certain research a lower energy of 1.5 GeV is advantageous. A description of how the new low energy mode was achieved is given, including extraction on the fly from the booster synchrotron and scaling of the storage ring lattice.

MOPEA004	Beam Lifetime in the ASTRID and ASTRID2 Synchrotron Light Sources: Excitations and Vacuum Dependences	vacuum, ion, emittance, electron	67
	J.S. Nielsen, N. Hertel, S.P. Møller ISA, Aarhus, Denmark
	The beam lifetime is a very important parameter for synchrotron light sources without top-up, and sometimes more important than the lowest possible vertical beam emittance. At the ASTRID synchrotron light source, we have for many years routinely applied a phase modulation of the accelerating RF field, together with a vertical excitation of the beam at the first vertical betatron frequency. These two effects increase the beam lifetime from about 3 hours to more than 100 hours at 150 mA. Lifetime measurements as function of modulation and excitation parameters will be presented. Additionally, measurements of the beam lifetime in ASTRID and ASTRID2 as function of vacuum pressure will be presented.

MOPEA019	Studies of Bunch-bunch Interactions in the ANKA Storage Ring with Coherent Synchrotron Radiation using an Ultra-fast Terahertz Detection System	radiation, storage-ring, wakefield, synchrotron-radiation	109
	A.-S. Müller, B.M. Balzer, C.M. Caselle, N. Hiller, M. Hofherr, K.S. Ilin, V. Judin, B. Kehrer, S. Marsching, S. Naknaimueang, M.J. Nasse, J. Raasch, A. Scheuring, M. Schuh, M. Schwarz, M. Siegel, N.J. Smale, J.L. Steinmann, P. Thoma, M. Weber, S. Wuensch KIT, Karlsruhe, Germany
	Funding: Supported by Initiative and Networking Fund of the Helmholtz Association under contract No. VH-NG-320 and German Federal Ministry of Education and Research under Grant. Noss. 05K10VKC and 05K2010VKD In the low-alpha operation mode of the ANKA synchrotron light source, coherent synchrotron radiation (CSR) is emitted from short electron bunches. Depending on the bunch current, the radiation shows bursts of high intensity. These bursts of high intensity THz radiation display a time evolution which can be observed only on long time scales with respect to the revolution period. In addition, long range wake fields can introduce a correlation between the bunches within a bunch train and thus modify the observed behavior. A novel detection system consisting of an ultra-fast superconducting THz detector and data acquisition system was used to investigate correlations visible on the bursting pattern and to study the interactions of very short pulses in the ANKA storage ring.

MOPEA020	Comparison of Different Approaches to Determine the Bursting Threshold at ANKA	radiation, storage-ring, electron, synchrotron-radiation	112
	P. Schönfeldt, N. Hiller, V. Judin, A.-S. Müller, M. Schwarz, J.L. Steinmann KIT, Karlsruhe, Germany
	The synchrotron light source ANKA at the Karlsruhe Institute of Technology provides a dedicated low-α-optics. In this mode bursting of Coherent Synchrotron Radiation (CSR) is observed for bunch charges above a threshold that depends on beam parameters. This threshold can be determined by several approaches, e.g. bunch lengthening or changes in the THz radiation spectra. This paper compares different methods and their implementation at the ANKA storage ring outlining their advantages, disadvantages and limitations, including reliability and possibility of real time analysis.

MOPEA026	X-ray Powder Diffraction Beamline for the Iranian Light Source Facility	photon, electron, focusing, brilliance	130
	H. Khosroabadi, S. Amiri, H. Ghasem, A. Gholampour ILSF, Tehran, Iran H. Ghasem IPM, Tehran, Iran
	Iranian Light Source Facility (ILSF) project has been initiated since 2010 in order to design and construction of a synchrotron facility in Iran. In parallel with the machine’s activities, scientific committee, users community and beamline technical group are working on different aspects of the scientific and beamline design issues for the operating phase after construction. X-ray powder diffraction beamline is one of the most priorities in ILSF due to wide range of applications and big potential user community in Iran. Conceptual design report of this beamline operating in other worldwide synchrotrons have been studied and compared in details. The light source and schematic design of the beamline has been prepared in this study. Then, the parameters have been calculated and have been optimized by employing computational software such as XOP and SHADOW. The optical properties of the optical elements such as reflectivity, absorbance, Bragg diffraction, rocking curve, aberration, etc have been studied at this design, and the results have been compared with the other published results. The outcome and final results of this design progress will be discussed in details. References: Conceptual Design Report (2011, summer), ILSF, http://ilsf.ipm.ac.ir/. ** http://www.esrf.eu/UsersAndScience/Experiments/TBS/SciSoft/xop2.3.

MOPEA033	Status of Upgrade Project of the 1.2 GeV Booster Synchrotron at Tohoku University	booster, quadrupole, alignment, dipole	151
	F. Hinode, H. Hama, S. Kashiwagi, T. Muto, I. Nagasawa, K. Nanbu, Y. Shibasaki, K. Takahashi Tohoku University, Research Center for Electron Photon Science, Sendai, Japan
	The 1.2 GeV electron synchrotron has been operated for nuclear physics experiment since 1997 in Electron Light Science Centre, Tohoku University, in which the high energy gamma-rays via bremsstrahlung has been supplied for hadron physics. After the Great East Japan Earthquake in March 2011, recovery and reconstruction work of the accelerator complex is in progress vigorously. While the compact 90 MeV linac is newly constructed as the dedicated injector for the synchrotron, old power supplies of synchrotron magnets and also pulsed magnets for beam injection are going to be replaced in the synchrotron. Furthermore replacements of some quadrupole magnets to the combined function magnets with sextupole component are also on going. Modifying the ring optics so as to introduce the horizontal dispersion on the combined magnet position, this replacement work will make it possible to correct the chromaticity. At the present, power supplies and combined magnets have been manufactured and those installations will be completed soon. We will present the current status of upgrade project of the booster synchrotron.

MOPEA044	Maintenance Experience for Personnel Safety System at SSRF	controls, PLC, radiation, 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.

MOPEA072	Recent Improvement of the APS Booster Synchrotron	booster, lattice, emittance, injection	252
	C. Yao, R. Laird, V. Sajaev, N. Sereno, H. Shang, J. Wang, S. Xu ANL, Argonne, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-ACO2-O6CH11357. The APS booster injector is a 7-GeV electron synchrotron. Several improvements have been implemented in the booster area, including the development of the 92-nm low emittance lattice, upgrading the ramp current readback ADC, and development of a new firing card for the main ramp supplies. Recently we have completed the commissioning of the low emittance lattice and it is now APS operational lattice. Combined with improvement in the optimization in the storage ring lattice and injection, we have achieved close to 100% storage ring injection efficiency. This report presents the improvements and measured beam parameters and the measured performance of the ramp control.

MOPFI007	SIS-18 RF Knock-Out Optimization Studies	extraction, resonance, dipole, septum	297
	M.M. Kirk, D. Ondreka, P.J. Spiller GSI, Darmstadt, Germany
	The extraction efficiency and spill temporal-structure of the SIS-18 heavy ion synchrotron are part of the upgrades to the GSI accelerator complex. Losses to the extraction septum can be minimised through implementation of the Hardt condition resulting however in a poorer quality of the spill microstructure at resolutions of a few microseconds due to lowering of the horizontal chromaticity from its 'natural' value. Ways to improve the extraction efficiency and spill microstructure are investigated with a tracking code. One possibility for improvement may be to use an alternative RF modulation applied to the knock-out exciter.

MOPFI010	Initial Beam Loss and Control of Dynamic Vacuum Effects in SIS18	injection, ion, collimation, vacuum	300
	Y. El-Hayek FIAS, Frankfurt am Main, Germany M.M. Kirk, D. Ondreka, P.J. Spiller GSI, Darmstadt, Germany U. Ratzinger IAP, Frankfurt am Main, Germany
	To stabilize the dynamic pressure in the SIS18, the systematic initial beam loss must be minimized. Beam Particles, which are lost on the vaccum chamber cause a local pressure increase. Thereby the collision rate between beam ions and residual gas particles and consequently beam loss by ionization is enhanced. The reduction and control of beam loss in the injection channel, during multiturn injection and during the Rf capture process has an outstanding importance for the vacuum dynamics. One way to minimize the initial losses in the synchrotron is to displace the beam loss into the transfer channel (TK) between UNILAC and SIS. In the transfer channel, the beam edges are trimmed by means of a collimator system and a sharply defined phase space area can be injected into SIS18. The effect of reduced initial beam loss on the vaccum dynamics is presented.

MOPFI030	Study of the Beam Injection and Extraction of the Proton Irradiation Accelerator	injection, proton, extraction, kicker	348
	Y.W. An, H.F. Ji, S. Wang IHEP, Beijing, People's Republic of China
	The proton irradiation accelerator is widely founded for industry application, and the extracted beam is required to have large intensity as a pulse beam or uniform distribution for scanning. A multi-turn injection is adopted and the proton beam is injected into the ring with the energy of 10MeV. In order to increase injection beam intensity, local bump orbit including two-bump, three-bump and four-bump is well studied and optimized, and the septum magnet thickness and localization are also studied for an effective injection. A RF knock-out method is used for slow extraction due to the fast response character. In order to decrease the global spill, double RF kicker and the control of the aptitude modulation (AM) function of the transverse RF field are well studied.

MOPFI046	Transverse RF Kicker Excitation and Longitudinal RF Noise Diffusion for Slow Extraction from SAPT	extraction, kicker, simulation, resonance	386
	L. Ouyang, M. Gu, D.M. Li, Q. Yuan, M.Z. Zhang SINAP, Shanghai, People's Republic of China
	Two key techniques used in the slow extraction from synchrotron accelerator: longitudinal RF stochastic noise acceleration, and transverse RF knock out excitation have been studied in this paper. Detailed comparison have revealed the potentials and limits of both methods. For the longitudinal RF stochastic acceleration excitation, the focus has been the phase space compression of particles, which makes the them to hasten around the RF bucket of the cavity, thus to lower the senstivity to ripple. For the transverse RF knock out excitation, the emphasis have been optimal schemes of amplitude modulation and frequency modulation of the RF singals. The optimizations are also used to lower the senstivity of the beam to the ripple and to enhance the uniformity of the extracted beam.

MOPFI063	Progress on Designs for 180 MeV Injection into the ISIS Synchrotron	injection, dipole, septum, stripper	428
	B. Jones, D.J. Adams, B.S. Drumm, M.C. Hughes, A.J. McFarland, C.M. Warsop STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
	The ISIS Facility at the Rutherford Appleton Laboratory in the UK produces intense neutron and muon beams for condensed matter research. It operates at 50Hz accelerating beam via a 70 MeV H⁻ linac and an 800 MeV proton synchrotron, delivering a mean beam power of 0.2 MW. As an initial step towards megawatt operations at ISIS, a study of replacement of the existing injector with a new 180 MeV H⁻ linac has recently been completed. This could enable an increase in beam power to approximately 0.5 MW. The ISIS Facility at the Rutherford Appleton Laboratory in the UK produces intense neutron and muon beams for condensed matter research. It accelerates 3×10¹³ protons per pulse (ppp) at 50 Hz through a 70 MeV H− linac and an 800 MeV proton synchrotron, delivering a mean beam power of ~0.2 MW. A favoured first step to upgrade ISIS towards the megawatt regime is replacement of the linac with a new 180 MeV injector described in [1]. Studies of this upgrade, which aims to increase mean beam power up to 0.5 MW are outlined in [2]. This paper reports on recent development of the designs including the injection septum, dipole power supplies and detailed tracking of partially stripped foil products.

MOPME007	High Resolution Synchrotron Light Analysis at ELSA	diagnostics, vacuum, optics, electron	482
	S. Zander, F. Frommberger, P. Hänisch, W. Hillert, M.T. Switka ELSA, Bonn, Germany
	Funding: Funded by the DFG within the SFB/ TR 16 The Electron Stretcher Facility ELSA provides polarized electrons with energies up to 3.5 GeV for external hadron experiments. In order to suffice the need of stored beam intensities towards 200 mA, advanced beam instability studies need to be carried out. An external diagnostic beamline for synchrotron light analysis has been set up and provides the space for multiple diagnostic tools including a streak camera with time resolution of < 1 ps. Beam profile measurements are expected to identify instabilities and reveal their thresholds. The effect of adequate countermeasures is subject to analysis. The current status of the beamline development will be presented.

MOPME023	ORBIT Beam Simulation Progress in the 3-GeV Rapid Cycling Synchrotron of J-PARC	simulation, lattice, injection, impedance	521
	P.K. Saha, H. Harada, H. Hotchi, Y. Shobuda, M. Yamamoto JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan J.A. Holmes ORNL, Oak Ridge, Tennessee, USA S. Kato Tohoku University, Graduate School of Science, Sendai, Japan
	We have made a numerous progress for beam simulation in the 3-GeV RCS (Rapid Cycling Synchrotron) of J-PARC (Japan Proton Accelerator Research Complex) by using 3-D particle tracking code, ORBIT. Namely, the TEAPOT lattice file used for ORBIT tracking has been made to give exactly same results to that with SAD model used for the RCS beam commissioning. In addition, time dependent lattice functions of the injection chicane magnets and similar other time dependent lattice imperfections, which are already found to have significant influences on the beam losses in the real machine have also been successfully introduced. At present, time dependent transverse and longitudinal impedances are going to be introduced. That should prove the ORBIT code much more matured for beam simulations in synchrotrons. Latest beam simulation results illustrating these new realistic features are presented.

MOPME039	A New Method of Acquiring Fast Beam Transversal Profile in the Storage Ring	factory, electron, synchrotron-radiation, simulation	556
	C. Cheng, P. Lu, B.G. Sun, K. Tang, F.F. Wu, Y.Y. Xiao, Y.L. Yang, Z.R. Zhou, J.Y. Zou USTC/NSRL, Hefei, Anhui, People's Republic of China
	A new method of acquiring fast beam transverse profile has been developed and will be used in HLS II. This method is based on four signals from MAPMT (multi-anode photo-multiplier tube) and logarithm processing technique. First, the calculation formula of beam transversal size and position are deduced using above method. Then, the main performances (e.g. sensitivity and linearity range) are analyzed. According to stimulation result, regardless of cross-talk and inconsistency between channels, the size signal has a linear relation with size s when s=0.8-2mm and position d=±2mm, the position signal has a linear relation with position d and the linear range exceeds ±2mm when s=0.8-2mm. With channel cross-talk and channel inconsistency being considered, the stimulation results also are given. Finally, a fast beam transverse profile monitor is designed and provides turn-by-turn measurement of the beam transverse profile.

MOPME042	A PRELIMINARY SIMULATION OF BPM SIGNAL DIODE DETECTOR FOR HLS II TUNE MEASUREMENT SYSTEM*	simulation, betatron, storage-ring, pick-up	565
	J.J. Zheng, P. Lu, T.J. Ma, B.G. Sun, Y.L. Yang, J.Y. Zou USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: Supported by National Natural Science Foundation of China (11105141, 11175173) and the Fundamental Research Funds for the Central Universities (WK2310000015) A high sensitivity BPM signal detection front-end electronics has been designed for HLS II tune measurement system according to the HLS II upgrade requirements. Classical tune measurement systems filter out just one or a few of these betatron sidebands frequency. As a consequence, most of the betatron energy is dropped and only a very small energy remains for further processing. A new method, referred to as Direct Diode Detection (3D) by LHC[1], improves the situation. In this paper, the HLS II BPM signals have been calculated out in time domain and frequency domain. Basing on the characteristics of HLS II BPM signal, a preliminary simulation is performed to test and verify the feasibility of diode detector for HLS II tune measurement system. The simulation results clearly show that the technique of diode-based circuit can be applied to HLS II tune measurement.

MOPME053	Point Spread Function Study of X-ray Pinhole Camera in SSRF	radiation, synchrotron-radiation, emittance, storage-ring	592
	Z.C. Chen, J. Chen, G.Q. Huang, Y.B. Leng SSRF, Shanghai, People's Republic of China
	Funding: Supported by National Natural Science Foundation of China (11075198) An X-ray Pinhole Camera that has been used to present the transverse beam size with an intuitive grasp of the distribution of the beam radiation was installed on one beam-line of the storage ring in Shanghai Synchrotron Radiation Facility (SSRF). The real beam size however is a function of the image size of the CCD camera and the point spread function (PSF) of the system. The PSF was calculated but poorly tested. This article will present the measurement of the PSF with a series of beam based experiments and the consistency with the theoretical beam size.

MOPME054	Bunch-by-bunch Beam Position and Charge Monitor based on Broadband Scope in SSRF	injection, storage-ring, pick-up, synchrotron-radiation	595
	Y. Yang, Y.B. Leng, Y.B. Yan, N. Zhang SSRF, Shanghai, People's Republic of China
	A bunch-by-bunch beam position and charge monitor system, based on a broadband oscilloscope, has been developed at SSRF. The beam positions of each bunch could be located independently in this system by using the original signals from the button-type pickups on the storage ring. The relative charge of each bunch could be obtained by the sum signal from the pickups. Using sum weighted average method, turn-by-turn beam position could be got from the bunch-by-bunch beam position data. The difference of each bunch beam position have been observed during injection at SSRF.

MOPME064	SLM and Flags for Booster of NSLS-II	booster, vacuum, radiation, synchrotron-radiation	622
	O.I. Meshkov, V. Smalyuk BINP SB RAS, Novosibirsk, Russia V.L. Dorokhov BINP, Novosibirsk, Russia
	Set of diagnostics of booster of NSLS-II includes 6 fluorescent screens (flags) and 2 synchrotron light monitors (SLM). The flags will be applied during booster commissioning for closing of the beam turn. They are also a useful tool in case of malfunction elimination. SLM will be used both for booster comissioning and for operation. The details of calibration and design of the devices are discussed.

MOPME073	Measurement of Schottky-like Signals from Linac Bunched Hadron Beams for Momentum Spread Evaluation	linac, cavity, pick-up, bunching	649
	P. Kowina, P. Forck, R. Singh GSI, Darmstadt, Germany F. Caspers CERN, Geneva, Switzerland R. Singh TEMF, TU Darmstadt, Darmstadt, Germany
	We present a novel method for the measurement of Linac beam parameters in the longitudinal phase space. The longitudinal momentum spread can be evaluated by means of Schottky type signal analysis of bunched beams. There is a close similarity between a repetitive Linac bunch train and a circulating beam with a single short batch in a large machine like the LHC. A dedicated longitudinal cavity pick-up was used in the Linac where resonance frequency and Q-value were carefully selected in order to get an optimum compromise between the unavoidable coherent signal and the desired incoherent part of the beam spectrum. A time domain gating similar to the 4.8 GHz LHC Schottky front-end is applied. As a cross-check of the validity of the interpretation in terms of momentum spread, the Linac beam is analyzed in the downstream synchrotron using standard Schottky methods. In principle, this approach can be understood as an extension of Schottky analysis for circular machines with a perfect “mixing” between subsequent bunch trains. This contribution describes the test set-up and discusses the results of the measurements with a heavy ion beam.

MOPWA001	Development of a High Precision Integrator for Analog Signals to Measure Magnetic Fields in Realtime	pick-up, ion, controls, 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.

MOPWA007	Operating Experience of Kicker Magnet System in the J-PARC 3GeV RCS	kicker, high-voltage, extraction, neutron	678
	K. Suganuma, M. Kinsho, T. Togashi, M. Watanabe JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
	The J-PARC 3-GeV rapid cycling synchrotron (RCS) has been provided proton beam to the Material and Life Science Facility (MLF)as well as to the 50 GeV Main Ring (MR). Proton beam is accelerated from 181 MeV to 3GeV in the RCS and immediately extracted it to the beam transport line to the MLF and the MR. Extraction kicker system is used for this fast extraction. The RCS has been operated for the neutron and MLF users program from December 23rd, 2008. At the beginning of user operation there were many troubles for the extraction kicker system, especially, thyratron which are used for switch of power supply often caused failure. The beam stop rate due to RCS extraction kicker system was more than 13% in the total beam stop of the J-PARC, establishment and operation experience of the tuning for power supply of the extraction kicker make the beam stop rate less than 0.5% in November 2012. In this paper, we are going to report about daily operation whose main is about operation of thyratron and the maintenance held in summer 2012. And　 We also going to report about the aptitude test of thyratron as a plan of the future.

MOPWA019	Digital Power Supply Controller Development Based on FPGA	power-supply, controls, booster, 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.

MOPWA041	The New SLS Beam Size Monitor, First Results	laser, emittance, polarization, radiation	759
	Á. Saá Hernández, N. Milas, M. Rohrer, V. Schlott, A. Streun PSI, Villigen PSI, Switzerland Å. Andersson, J. Breunlin MAX-lab, Lund, Sweden
	Funding: This research has received funding from the European Commission under the FP7-INFRASTRUCTURES-2010-1/INFRA-2010-2.2.11 project TIARA (CNI-PP). Grant agreement no. 261905. An extremely small vertical beam size of 3.6 μm, corresponding to a vertical emittance of 0.9 pm, only about five times bigger than the quantum limit, has been achieved at the storage ring of the Swiss Light Source (SLS). The measurement was performed by means of a beam size monitor based on the imaging of the vertically polarized synchrotron radiation in the visible and UV spectral ranges. However, the resolution limit of the monitor was reached during the last measurement campaign and prevented further emittance minimization. In the context of the work package “SLS Vertical Emittance Tuning” of the TIARA collaboration, a new improved monitor was built. It provides larger magnification, an increase of resolution and enables two complementary methods of measurement: imaging and interferometry. In this paper we present the design, installation, commissioning, performance studies and first results obtained with the new monitor.

MOPWA044	TLS Booster Measurement and Observation by New BPM Electronics	booster, quadrupole, extraction, kicker	768
	P.C. Chiu, J. Chen, Y.-S. Cheng, K.T. Hsu, S.Y. Hsu, K.H. Hu, C.H. Kuo NSRRC, Hsinchu, Taiwan
	Taiwan Light Source (TLS) is a 1.5 GeV synchrotron based light source and its booster synchrotron was delivered in 1992. Due to the new project Taiwan Photon Source proceeded at the same site, some up-to-date device are available now before TPS civil construction complete and temporarily adapted for TLS booster to improve its operations. The major parameters of the TLS booster synchrotron are measured. It also provides a chance to experience for the TPS project booster diagnostic.

MOPWA060	DITANET - An International Network in Beam Diagnostics	diagnostics, electron, photon, instrumentation	813
	C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom C.P. Welsch The University of Liverpool, Liverpool, United Kingdom
	Funding: Work supported by the EU under contract 215080. Beam diagnostics systems are essential constituents of any particle accelerator; they reveal the properties of a beam and how it behaves in a machine. Without an appropriate set of diagnostic elements, it would simply be impossible to operate any accelerator complex, let alone optimize its performance. Beam diagnostics is also a rich field in which a great variety of physical effects are made use of and consequently provides a wide interdisciplinary base for the training of researchers. The DITANET Consortium develops beyond state-of-the-art beam diagnostic techniques for hadron and electron accelerators and trained more than 20 researchers between 2008 and 2012. This contribution summarizes the network's research outcomes in beam instrumentation and diagnostics.

MOPWA066	Components of Heating and Fueling of Fusion Plasmas	high-voltage, simulation, controls, cathode	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.

MOPWA073	A Turn-by-turn Beam Profile Monitor using Visible Synchrotron Radiation at CESR-TA	electron, synchrotron-radiation, radiation, emittance	849
	S. Wang, D. L. Rubin, C.R. Strohman CLASSE, Ithaca, New York, USA R.F. Campbell, R. Holtzapple CalPoly, San Luis Obispo, California, USA
	Funding: Work supported by the National Science Foundation and Department of Energy under contract numbers PHY-0734867, PHY-1002467, DMR-0936384, and DE-FC02-08ER41538, DE-SC0006505 A fast beam profile monitor using visible synchrotron radiation (SR) has been constructed and installed in Cornell Electron Storage Ring. This monitor utilizes fast readout electronics based on the Hamamatsu H7260K multi-anode photomultiplier, which has a 32-channel linear array with 1mm channel pitch and sub-nanosecond rise time. In a low emittance lattice at 2 GeV, a double-slit interferometer is employed to measure the horizontal beam size. After careful calibration of the interference pattern, the horizontal beam size within a range of 100 to 500 microns can be measured with a precision of ±5 microns. Due to finite array size, the small vertical beam size is measured by imaging the pi-polarized component of the SR. The fast beam profile monitor is capable of measuring bunch-by-bunch turn-by-turn transverse beam sizes, which eliminates beam jitter inherent when imaging the average beam size with a CCD camera. Details of hardware and software controls are also discussed.

MOPWO005	Simulating Spin Dynamics and Depolarization using POLE	resonance, simulation, polarization, synchrotron-radiation	891
	J.F. Schmidt, O. Boldt, F. Frommberger, W. Hillert ELSA, Bonn, Germany
	Funding: BMBF The spin dynamics in circular accelerators with fast energy ramps, or short storage times of up to some seconds, can be investigated with spin tracking appropriately. Additionally, the spin motion of lepton beams is affected significantly by synchrotron radiation. Hence, spin dynamics simulations require spin tracking with a large number of particles to compute the beam polarization and thus take considerably long computing times. Therefore, high efficiency is crucial to perform systematic polarization studies. The new simulation tool POLE provides the ability to balance accuracy against computing time. To that end, adjustable approximations of magnetic fields and synchrotron radiation are implemented. POLE is accessible for a wide range of lepton storage rings because it uses the common MAD-X lattice files and the corresponding particle tracking results.

MOPWO006	Eigenmode Computation for the GSI SIS18 Ferrite Cavity	cavity, resonance, heavy-ion, ion	894
	K. Klopfer, W. Ackermann, T. Weiland TEMF, TU Darmstadt, Darmstadt, Germany
	Funding: Supported by GSI At the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt the heavy-ion synchrotron SIS18 is operated to further accelerate stable nuclei of elements with different atomic numbers. Two ferrite-loaded cavity resonators are installed within this ring. During the acceleration phase their resonance frequency has to be adjusted to the revolution frequency of the heavy-ions to reflect their increasing speed. To this end, dedicated biased ferrite-ring cores are installed inside the cavities for a broad frequency tuning. By properly choosing a suited bias current, the differential permeability of the ferrite material is modified, which finally enables to adjust the eigenfrequency of the resonator system. Consequently, the actual resonance frequency strongly depends on the magnetic properties of the ferrites. The goal of the current study is to numerically determine the lowest eigensolutions of the GSI SIS18 ferrite-loaded cavity. For this purpose, a new solver based on the Finite Integration Technique has been developed.

MOPWO037	SixTrack Simulation of Off-momentum Cleaning in LHC	simulation, radiation, betatron, synchrotron-radiation	972
	E. Quaranta, R. Bruce, S. Redaelli CERN, Geneva, Switzerland
	In the LHC, high-amplitude particles are cleaned by either betatron collimators or momentum collimators. Previously, betatron losses have been considered more important, but measurements during the first years of operation show high losses also in the off-momentum cleaning insertion. This causes a significant radiation dose to warm magnets downstream of the collimators. Our work in this paper aims at simulating with SixTrack the off-momentum particles, driven into the momentum collimators by radiation damping outside the RF system acceptance. The results are an important ingredient in assessing the effectiveness of new passive absorbers to protect the warm magnets.

MOPWO087	Parameter Estimation of the Exponentially Damped Sinusoid for Noisy Signals	closed-orbit, neutron, damping, feedback	1079
	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 The damped sinusoid equation is a common model for many scientific processes involving damped periodic signals. Here we present two methods for estimating the damped sinusoid parameters for noisy signals. Both methods are based upon an exact, closed form solution to fit the parameters for signals without noise, and they estimate the parameters for the noisy signals by the statistical maximum likelihood criterion. The first method relies on an optimizer to minimize the mean square signal error. The second method estimates the parameters by direct calculation and is suitable when the signal noise is small and the frequencies are sufficiently far from the integer and half integer values.

TUOAB202	ILSF, A Third Generation Light Source Laboratory in Iran	storage-ring, dipole, quadrupole, cavity	1137
	J. Rahighi, M.R. Khabazi IPM, Tehran, Iran E. Ahmadi, H. Ajam, M. Akbari, S. Amiri, A. Babaei, J. Dehghani, R. Eghbali, J. Etemad Moghadam, S. Fatehi, M. Fereidani, H. Ghasem, A. Gholampour, A. Iraji, M. Jafarzadeh, B. Kamkari, S. Kashani, P. Khodadoost, H. Khosroabadi, M. Moradi, H. Oveisi, S. Pirani, M. Rahimi, M. Razazian, A. Sadeghipanah, F. Saeidi, R. Safian, E. Salimi, Kh.S. Sarhadi, O. Seify, M.Sh. Shafiee, A. Shahveh, A. Shahverdi, D. Shirangi, E.H. Yousefi ILSF, Tehran, Iran D. Einfeld CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	The Iranian Light Source Facility (ILSF) project is a first large scale accelerator facility which is currently under planning in Iran. The circumference of the storage ring is 297.6 m with the energy of 3 GeV. The facility will be built on a land of 100 hectares area in the city of Qazvin, located 150 km West of Tehran. The city is surrounded by many universities, research centers and industrial companies. The design and construction of prototype items such as radio frequency solid state amplifier, dipole magnets, highly stable magnet power supplies and girders have already begun. A low field H-type dipole magnet with the central field of 0.5T at the gap of 34mm and length of 500mm was built and tested in site. Also a prototype storage ring quadrupole with a 18 T/m gradient and 233 iron length is in now in fabrication process. Site selection studies, including geotechnical and seismological measurements are being performed. Conceptual Design Report, CDR, as the first milestone of the project has been published on October 2012.
	Slides TUOAB202 [5.173 MB]

TUODB201	Recent Progress on the Development of a High Gradient RF System using High Impedance Magnetic Alloy, FT3L	cavity, impedance, acceleration, controls	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]

TUPEA005	Effects of Quantum Diffusion on Electron Trajectories and Spontaneous Synchrotron Radiation Emission	electron, radiation, photon, undulator	1170
	I.V. Agapov, G. Geloni XFEL. EU, Hamburg, Germany O.V. Chubar BNL, Upton, Long Island, New York, USA
	For various cases, e.g. in the long undulator sections of the European XFEL, quantum diffusion and energy loss have a noticable effect on the electron trajectory, which in turn affects the properties of the emitted radiation. We discuss approaches to modelling the electron dynamics taking this into account and the effect it has on spontaneous radiation emission.

TUPFI063	Electromagnetic Coupling between High Intensity LHC Beams and the Synchrotron Radiation Monitor Light Extraction System	simulation, resonance, impedance, extraction	1493
	F. Roncarolo, W. Andreazza, A. Bertarelli, E. Bravin, F. Caspers, M. Garlaschè, A. Goldblatt, J-J. Gras, O.R. Jones, T. Lefèvre, E. Métral, A.A. Nosych, B. Salvant, G. Trad, R. Veness, C. Vollinger, M. Wendt CERN, Geneva, Switzerland
	The CERN LHC is equipped with two Synchrotron Radiation Monitor systems used to characterise transverse and longitudinal beam distributions. Since the end of the 2011 LHC run the light extraction system, based on a retractable mirror, has suffered deformation and mechanical failure that is correlated to the increase in beam intensity. Temperature probes have associated these observations to a strong heating of the mirror support with a dependence on the longitudinal bunch length and shape, indicating the origin as electromagnetic coupling between the beam and the structure. This paper combines all this information with the aim of characterising and improving the system in view of its upgrade during the current LHC shutdown. Beam-based observations are presented along with electromagnetic and thermomechanical simulations and complemented by laboratory measurements, including the study of the RF properties of different mirror bulk and coating materials.

TUPME011	Simulated Beam-beam Limit for Circular Higgs Factories	luminosity, simulation, beam-beam-effects, radiation	1586
	K. Ohmi KEK, Ibaraki, Japan F. Zimmermann CERN, Geneva, Switzerland
	We report simulation studies of the beam-beam limit for two proposed circular e⁺e⁻ Higgs factories with circumference of 27 and 80 km, respectively, called LEP3 and TLEP. In particular we investigate the dependence of the steady-state luminosity and transverse beam sizes on the synchrotron tune (or momentum compaction factor) and on the betatron tunes, as well as the consequences of the strong radiation damping and the implications of the large hourglass effect.

TUPME017	Validation of the Microwave Instability in the Damping Ring of SuperKEKB using VFP Solver	impedance, damping, simulation, wakefield	1604
	L. Wang SLAC, Menlo Park, California, USA H. Ikeda, K. Ohmi, K. Oide, D. Zhou KEK, Ibaraki, Japan
	Microwave instability driven by CSR impedance in the damping ring of Super-KEKB is a concern due to its high bunch current. To understand the beam dynamics, we simulate the microwave instability using Vlasov-Fokker-Planck (VFP) solver. The longitudinal wake potential is calculated as a sum of the contributions due to vacuum chamber components distributed around the ring, including geometry wake field and CSR wake. To improve the accuracy of the simulation of microwave instability, the coherent synchrotron radiation impedance is calculated to very high frequency to get more accurate wake field with a short bunch. The CSR wake is much larger than the geometry wake. The threshold is just above the design current and saw-tooth type of instability is found above the threshold.

TUPME018	Construction of New 90 MeV Injector Linac for the 1.2 GeV Booster Synchrotron at Tohoku University	linac, gun, electron, quadrupole	1607
	S. Kashiwagi, H. Hama, F. Hinode, M. Kawai, T. Muto, I. Nagasawa, K. Nanbu, Y. Shibasaki, K. Takahashi Tohoku University, Research Center for Electron Photon Science, Sendai, Japan N.Y. Huang NTHU, Hsinchu, Taiwan
	The Great East Japan Earthquake (March 11, 2011) has inflicted enormous damage on the accelerator facility of Research Center for Electron Photon Science, Tohoku University. A 300 MeV linac operated for 46 years as an accelerator for radioisotope production and also as an injector of the 1.2 GeV booster synchrotron for nuclear physics experiments. The accelerator will be rebuilt with all the recyclable components. New small linac is constructed as the injector for the booster synchrotron. The injector consists of thermionic rf-gun, two 3m-long accelerating structures, and transport line to the synchrotron. The maximum energy of injector is 90 MeV with beam loading. The detail of the injector linac is introduced in this conference.

TUPME021	Optimization Parameter Design of a Circular e⁺e⁻ Higgs Factory	luminosity, factory, emittance, collider	1616
	D. Wang, Y.W. An, J. Gao, H. Geng, Y.Y. Guo, Q. Qin, N. Wang, S. Wang, M. Xiao, G. Xu, S.Y. Xu IHEP, Beijing, People's Republic of China
	Funding: NSFC:11175192 In this paper we will show a genral method of how to make an optimized parameter design of a circular e⁺e⁻ Higgs Factory by using analytical expression of maximum beam-beam parameter and beamstrahlung beam lifetime started from given design goal and technical limitations. A parameter space has been explored.

TUPME045	Turn-by-turn Measurements in the KEK-ATF	damping, injection, betatron, emittance	1664
	Y. Renier, Y. Papaphilippou, R. Tomás, M. Wendt CERN, Geneva, Switzerland N. Eddy Fermilab, Batavia, USA K. Kubo, S. Kuroda, T. Naito, T. Okugi, N. Terunuma, J. Urakawa KEK, Ibaraki, Japan
	The ATF damping ring has been upgraded with new read-out electronics for the beam position monitors (BPM), capable to acquire the beam orbits on a turn-by-turn basis, as well as in a high resolution averaging mode. The new BPM system allows to improve optic corrections and to achieve an even smaller vertical emittance (<2pm). Experimental results are presented based on turn-by-turn beam orbit measurements in the ring, for estimating the beta functions and dispersion along the lattice. A fast method to measure spectral line amplitude in a few turns is also presented, including the evaluation of chromaticity.

TUPME056	3.5 GeV Superconducting Stacking Ring for Compton Based Polarized Positrons Source of CLIC	positron, injection, damping, emittance	1697
	E.V. Bulyak, P. Gladkikh, A.A. Kalamayko NSC/KIPT, Kharkov, Ukraine T. Omori, J. Urakawa, K. Yokoya KEK, Ibaraki, Japan L. Rinolfi, F. Zimmermann CERN, Geneva, Switzerland
	This paper describes 3.5 GeV superconducting storage ring dedicated to positron accumulation as part of a polarized positron source for CLIC, based on Compton scattering in a Compton storage ring. The superconducting stacking ring can provide a synchrotron damping time of order 250 microseconds. Together with combined injection scheme in the longitudinal and transverse plane, such a ring may solve the problem of accumulating a positron beam with efficiency close to 95 % and with the beam intensity required for CLIC.

TUPWA015	The Study of Bunch Lengthening in Electron Storage Ring	impedance, storage-ring, luminosity, electron	1757
	Y. Li, L. Wang, Y. Zhang IHEP, Beijing, People's Republic of China
	The bunch length of electron storage ring of BEPCII was measured repeatedly during steady synchronous mode and streak camera was calibrated well. From the bench lengthening , the coupling impedance of the whole ring was estimated, which was according with theoretic impedance budget . Meanwhile, the small ap optics for improving the luminosity was feasible in collision mode form synchronous result .

TUPWA024	The Beam Gass Coulomb Scattering in Electron Storage Ring	scattering, simulation, electron, radiation	1778
	X.L. Yu, Z. Bai, W.W. Gao, W. Li, L. Wang USTC/NSRL, Hefei, Anhui, People's Republic of China
	Among the various factors which determine the beam life time of the HLSII electron storage ring, the beam loss due to the scattering on residual gas is simulated using MC method. The paper will give the process of elastic and inelastic scattering, and the probability of each scattering is calculated, then using MC sampling to decide which particles will participate in the collision. Tracking the beam with scattering of beam-gas included, the spatial distribution of beam will be obtained. Finally we will give the influence analysis of beam-gas scattering.

TUPWA040	Loss of Landau Damping for Inductive Impedance in a Double RF System	damping, emittance, simulation, impedance	1796
	T. Argyropoulos, E.N. Shaposhnikova CERN, Geneva, Switzerland A.V. Burov Fermilab, Batavia, USA
	In this paper the thresholds of the loss of Landau damping due to the presence of inductive impedance in a single and double harmonic RF systems are determined, both from calculations and particle simulations. High harmonic RF system, operating in bunch lengthening mode is used in many accelerators with space charge or inductive impedance to reduce the peak line density or stabilize the beam. An analytical approach, based on emerging of the discrete Van Kampen modes, shows that improved stability in a double RF system can be achieved only below some critical value of longitudinal emittance. Above this threshold, a phase shift of more than 15 degrees between the two RF components is proven to stabilize the bunch. These results, confirmed also by particle simulations, are able to explain now observations during the ppbar operation of the SPS. The thresholds in bunch shortening mode as well as in a single RF case are compared with this regime.

TUPWA063	Dependence of Vertical Beam Dynamics Influenced by Electron Clouds at CesrTA on Variations in Bunch Spacing and Vertical Chromaticity	electron, positron, emittance, feedback	1847
	R. Holtzapple, R.F. Campbell, E.L. Holtzapple CalPoly, San Luis Obispo, California, USA M.G. Billing, K.R. Butler, G. Dugan, M.J. Forster, B.K. Heltsley, G. Ramirez, N.T. Rider, J.P. Shanks, K.G. Sonnad CLASSE, Ithaca, New York, USA J.W. Flanagan KEK, Ibaraki, Japan
	Funding: Work supported by DOE Award DE-FC02-08ER41538, NSF Award PHY-0734867, PHY-1068662 and the Lepton Collider R&D Coop. Agreement: NSF Award PHY-1002467 Experiments have been performed on the Cornell Electron-Positron Storage Ring Test Accelerator (CesrTA) to probe the interaction of the electron cloud with a 2-Gev stored positron beam. The purpose of these experiments was to characterize the beam–electron cloud interactions by varying the vertical chromaticity and bunch spacing. These experiments were performed on a 30-bunch positron train, at a fixed current of 0.75mA/bunch, where the bunch spacing was varied between 4 and 28ns at three different vertical chromaticity settings. The vertical beam dynamics of the stored beam, in the presence of the electron cloud, was quantified using the x-ray beam size monitor (xBSM) that is used to measure the bunch-by-bunch, turn-by-turn vertical beam size of the bunch trains. In this paper, we report the results from these experiments and discuss the effects of the electron cloud on the CesrTA beam dynamics.

TUPWO015	Off-Energy Injection Into Newsubaru	injection, lattice, septum, betatron	1913
	Y. Shoji LASTI, Hyogo, Japan Y. Minagawa, Y. Takemura JASRI/SPring-8, Hyogo-ken, Japan
	NewSUBARU is temporarily operated in non-achromatic mode for the research using chromaticity modulation. At this special mode, a normal injection scheme does not work because of the larger stored beam size and smaller ring acceptance. In order to obtain good injection efficiency, which enables top-up operation, the injected beam energy is displaced from the ring energy. The finite dispersion of 1.1 m at the injection point and the energy displacement of 0.7% reduce the betatron oscillation amplitude of the injected beam. A trade off is a synchrotron oscillation produced by the energy mismatch. Using this technique, it became possible to inject new beam using a closed fast injection bump and also a top-up operation. Although it is not possible to inject beam to a normal achromatic lattice using a closed bump. Especially in non-achromatic quasi-isochronous ring, it would be possible that the energy mismatch is reduced by the betatron amplitude dependent shift of the equilibrium energy.

TUPWO023	Parasitic Slow Exraction of Extremely Weak Beam From a High-intensity Proton Rapid Cycling Synchroton	scattering, extraction, proton, simulation	1931
	Y. Zou, H.T. Jing, C. Meng, J.Y. Tang, Z. Yang IHEP, Beijing, People's Republic of China
	This paper proposes a new method to extract extremely weak beam from a high-intensity proton rapid cycling synchrotron in the parasitic mode, while maintaining the normal fast extraction. The usual slow extraction from a synchrotron by third-order resonance method cannot be applied in a RCS due to very short flat-top at the extraction energy. This is even more difficult when it is high-intensity synchrotron due to the strict control on beam loss. The parasitic slow extraction method to extract extremely weak beam from the RCS of CSNS has been studied in details. By moving only beam halo to a scatting foil in the arc region by a local orbit bump in about 2 ms before the fast extraction, one can extract a very small part of the scattered particles with very limited beam loss in the process. At 1.6 GeV and 62.5 A in beam power, halo particles of about 10^-4 total particles are involved in the parasitic slow extraction can result in a beam intensity of 2105 protons per cycle or lower. Detailed studies including scattering effect in the foil, orbit bumps by bump magnets and energy displacement by adjusting RF, and multi-particle simulations by ORBIT and TURTLE codes are presented.

TUPWO054	Recent Results from the EMMA Experiment	acceleration, simulation, betatron, closed-orbit	1988
	B.D. Muratori, J.K. Jones STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom R. Appleby, J.M. Garland, H.L. Owen UMAN, Manchester, United Kingdom J.S. Berg, F. Méot BNL, Upton, Long Island, New York, USA C.S. Edmonds, J.K. Jones, I.W. Kirkman, B.D. Muratori, A. Wolski Cockcroft Institute, Warrington, Cheshire, United Kingdom C.S. Edmonds, I.W. Kirkman, A. Wolski The University of Liverpool, Liverpool, United Kingdom D.J. Kelliher, S. Machida STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom J. Pasternak STFC/RAL, Chilton, Didcot, Oxon, United Kingdom J. Pasternak Imperial College of Science and Technology, Department of Physics, London, United Kingdom
	EMMA (Electron Model for Many Applications) is a prototype non-scaling electron FFAG hosted at Daresbury Laboratory. After a recent demonstration of acceleration in the serpentine channel, the injected EMMA beam was further studied. This entails the continuation of the exploration of the large transverse and longitudinal acceptance and the effects of slower integer tune crossing on the betatron amplitude. A single closed orbit correction that is effective at multiple momenta (and hence over a significant range in tune space) was implemented. A comparison with a detailed model based on measured field maps, and the experimental mapping of the machine by relating the initial and final phase space coordinates was also done. These recent results together with more practical improvements such as injection orbit matching with real-time monitoring of the coordinates in the transverse phase space will be reported in this paper.

TUPWO055	Phase Rotation Experiment at EMMA for testing Applicability of a Non-scaling FFAG for PRISM System	extraction, acceleration, background, electron	1991
	B.D. Muratori, J.K. Jones STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom R.T.P. D'Arcy UCL, London, United Kingdom J.K. Jones, B.D. Muratori Cockcroft Institute, Warrington, Cheshire, United Kingdom D.J. Kelliher, S. Machida STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom H.L. Owen UMAN, Manchester, United Kingdom J. Pasternak STFC/RAL, Chilton, Didcot, Oxon, United Kingdom J. Pasternak Imperial College of Science and Technology, Department of Physics, London, United Kingdom
	EMMA is the world’s first non-scaling FFAG, based at Daresbury Laboratory. EMMA has a very large acceptance and has demonstrated acceleration in the serpentine channel. PRISM (Phase Rotated Intense Slow Muon source) is a next generation muon to electron conversion experiment aiming to obtain intense quasi-monochromatic low energy muon beams by performing RF phase rotation in an FFAG ring. Current baseline design for PRISM applies the scaling FFAG ring, but an alternative machine could be based on a ns-FFAG principle. As the transverse-longitudinal coupling is present in ns-FFAGs due to a natural chromaticity, its effect on the final energy spread and beam quality needs to be tested. In order to gauge the expected results, an experiment was designed to be performed on EMMA. We report here the details of this experiment and the results gathered from EMMA operation.

TUPWO061	Design of a Soft Orbit Bump for FEL Mirror Protection at Duke FEL/HIGS Facility	FEL, radiation, electron, synchrotron-radiation	2006
	H. Hao, J.Y. Li, S.F. Mikhailov, Y.K. Wu FEL/Duke University, Durham, North Carolina, USA
	Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033. In an oscillator Free-Electron Laser (FEL) with a high energy electron beam, it is critical to minimize harmful high-energy radiation on the downstream FEL mirror in order to increase its lifetime. At the High Intensity Gamma-ray Source (HIGS) facility at Duke University, effort has been devoted to developing a variety of techniques to reduce the amount of radiation on the FEL mirror. One of the most effective methods was the use of a set of adjustable in-vacuum apertures to block harmonic radiation from FEL wigglers. In recent studies, it was determined that the edge radiation from the end-of-the-arc bending magnet is the main source of UV/VUV and x-ray radiation which causes mirror damage. To mitigate this effect, a soft orbit bump is designed to change the displacement and angle of the electron beam around the end-of-the-arc area. This soft orbit bump is developed using the multi-objective optimization technique. Calculation shows the soft orbit bump can significantly reduce the flux of high energy photons on the FEL mirror. Study is also performed to determine the impact of this orbit bump on the injection, beam lifetime, and the FEL and gamma-ray operation at HIGS facility.

WEXB101	Optics Optimization for Reducing Collective Effects and Raising Instability Thresholds in Lepton and Hadron Rings	optics, emittance, collective-effects, brightness	2033
	Y. Papaphilippou, F. Antoniou, H. Bartosik CERN, Geneva, Switzerland
	This paper covers recent progress in the design of optics solutions to minimize collective effects such as beam instabilities, intra-beam scattering or space charge in hadron and lepton rings. The necessary steps are reviewed for designing the optics of high-intensity and high-brightness synchrotrons but also ultra-low emittance lepton storage rings, whose performance is strongly dominated by collective effects. Particular emphasis is given to proposed and existing designs illustrated by simulations and beam measurements.
	Slides WEXB101 [24.511 MB]

WEOAB101	Single Particle Tracking for Simultaneous Long and Short Electron Bunches in the BESSY II Storage Ring	cavity, HOM, simulation, optics	2038
	M. Ruprecht, A. Jankowiak, A. Neumann, M. Ries, G. Wüstefeld HZB, Berlin, Germany T. Weis DELTA, Dortmund, Germany
	A scheme where 1.5 ps and 15 ps long bunches (rms) can be stored simultaneously in the BESSY II storage ring has recently been proposed (BESSY^VSR). This paper presents simulations of single particle beam dynamics influenced by superconducting cavities used for the strong longitudinal beam focusing. The effect of RF jitter on (very short) bunches is investigated and results are discussed. Furthermore, possible effects on beam dynamics during ramp up and ramp down of the high gradient fields in the cavities are studied. The primary goal is to reveal preliminary design specifications for RF jitter on the basis of single particle dynamics. G. Wüstefeld, A. Jankowiak, J. Knobloch, M. Ries, Simultaneous Long and Short Electron Bunches in the BESSY II Storage Ring, Proceedings of IPAC2011, San Sebastián, Spain
	Slides WEOAB101 [3.955 MB]

WEOAB102	CSR-driven Longitudinal Single Bunch Instability Thresholds	impedance, resonance, damping, electron	2041
	P. Kuske BESSY GmbH, Berlin, Germany
	According to Bane, et al.* threshold currents should follow a quite simple scaling law. More detailed theoretical results for the underlying shielded CSR-interaction have been performed for BESSY-II and the MLS and will be presented in comparison with observations at these storage rings. It is found that there are parameter regions where the instability is weak and thus thresholds depend on damping time and synchrotron tune. Theoretical findings are in surprisingly good agreement with most of the observed instability features. * K.L. Bane, et al., Phys. Rev. ST-AB 13, 104402 (2010)
	Slides WEOAB102 [0.779 MB]

WEOBB202	Ultra-fast Data Acquisition System for Coherent Synchrotron Radiation Based on Superconducting Terahertz Detectors	radiation, electron, controls, 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]

WEPWA005	Experimental Characterization of the Coherent Harmonic Generation Source at the DELTA Storage Ring	laser, radiation, electron, undulator	2132
	M. Huck, H. Huck, M. Höner, S. Khan, R. Molo, A. Schick, P. Ungelenk DELTA, Dortmund, Germany S. Cramm, L. Plucinski, C.M. Schneider Forschungszentrum Jülich, Peter-Gruenberg-Institut-6, Jülich, Germany S. Döring, L. Plucinski, C.M. Schneider Universität Duisburg-Essen, Duisburg, Germany
	Funding: Work supported by DFG, BMBF, and by the Federal State NRW. The short-pulse facility at the 1.5-GeV synchrotron light source DELTA, operated by the TU Dortmund University, generates coherent VUV and THz radiation by Coherent Harmonic Generation (CHG). Here, a femtosecond laser pulse interacts with an electron bunch in an undulator causing a periodic energy modulation and subsequent micro-bunching, which gives rise to coherent radiation at harmonics of the seed wavelength. Rather than using Ti:Sapphire laser pulses at 795 nm directly, the second harmonic is employed for seeding since 2012. After significant modifications of the seed laser beamline and the dispersive chicane to improve the microbunching, the last commissioning steps include characterization of the CHG radiation and preparing the experimental setup at an existing VUV beamline for time-resolved photoemission spectroscopy. In this paper, the status of the project and recent experimental results are presented.

WEPWA006	Beam Heat Load Measurements with COLDDIAG at the Diamond Light Source	electron, synchrotron-radiation, radiation, impedance	2135
	S. Gerstl, S. Casalbuoni, A.W. Grau, T. Holubek, D. Saez de Jauregui, R. Voutta KIT, Eggenstein-Leopoldshafen, Germany R. Bartolini, M.P. Cox, E.C. Longhi, G. Rehm, J.C. Schouten, R.P. Walker Diamond, Oxfordshire, United Kingdom M. Migliorati, B. Spataro INFN/LNF, Frascati (Roma), Italy
	Understanding the heat load from an electron beam is still an open issue for the cryogenic design of superconducting insertion devices. COLDDIAG, a cold vacuum chamber for diagnostics was designed and built specially for this purpose. With the equipped instrumentation, which covers temperature sensors, pressure gauges, mass spectrometers as well as retarding field analyzers it is possible to measure the beam heat load, total pressure, and gas content as well as the net flux and energy of particles hitting the chamber walls. Following a failure after its first installation in November 2011, COLDDIAG was subsequently reinstalled in the Diamond storage ring in August 2012. We report on the preliminary results that have been obtained since then.

WEPWA007	First Tests with a Local and Integral Magnetic Field Measurement Setup for Conduction Cooled Superconducting Undulator Coils	undulator, vacuum, radiation, synchrotron-radiation	2138
	A.W. Grau, S. Casalbuoni, S. Gerstl, N. Glamann, T. Holubek, D. Saez de Jauregui KIT, Eggenstein-Leopoldshafen, Germany
	The magnetic field quality of insertion devices (IDs) has a significant influence on their performance. Therefore it is essential to characterize their magnetic properties and perform precise field measurements before installation in synchrotron light sources. Particularly for permanent magnet IDs the magnetic field measurement technology made significant progress during the last years and pushed the capabilities of synchrotron light sources. Even though for superconducting IDs the measurement settings are far more challenging similar major developments are required. As a part of our R&D program on superconducting IDs we perform quality assessment of their magnetic field properties. This contribution describes details, challenges and the first tests with the measurement equipment configurations to perform measurements of the integral and local magnetic field distributions of superconducting undulator coils up to 2 m length, in a cold (4.2 K), in-vacuum and cryogen free environment.

WEPWA012	Preliminary Design of Transfer Lines for the ILSF Accelerator Complex	booster, storage-ring, linac, electron	2153
	H. Ghasem IPM, Tehran, Iran E. Ahmadi, F. Saeidi ILSF, Tehran, Iran
	There are two transfer lines (T-lines) which link the Iranian Light Source Facility (ILSF) accelerator complex to gather. Several criterias have been considered in design stage of the T-lines. This paper gives linear optimization results of the designed T-lines based on the first layout of the ILSF.

WEPWA030	Using the Power Spectral Density Method to Characterize and Evaluate the X-ray Mirrors Surfaces	simulation, focusing, optics, brilliance	2196
	W.Q. Hua, F.G. Bian, Y.M. He, W.H. Lin, L. Song, J. Wang, N. Zhao SINAP, Shanghai, People's Republic of China
	Rapid progress in synchrotron X-ray beams’ coherence and X-ray optics performance places a high demand on characterization and evaluation of optical surface figure and slope errors and roughness on meter-long optics over spatial frequencies as short as 0.1mm. In this paper, the propagation model of hard X-ray beams through reflecting mirror surface is proposed based on wave-front propagation, and numerical simulations are performed for predicting the hard X-ray focusing performance of different imperfect mirrors using a Fresnel diffraction calculation. The imperfect mirror surface height maps synthesized from power spectral functions are used to analyze and evaluate the influences of different mirror surface errors on the reflected hard X-ray beam properties.

WEPWA035	Design of a Superconducting Undulator Magnet Prototype for SSRF	undulator, superconductivity, electron, storage-ring	2205
	Z.C. Zhang, J. Cui, J.Y. Jiang, M. Li, W. Li, J.P. Xu, J.J. Xu, J.F. Yu SINAP, Shanghai, People's Republic of China
	Funding: Project 11275254 supported by National Natural Science Foundation of China. A 0.65 T NbTi superconducting undulator magnet prototype with a period length of 16 mm and a period number of 5 for SSRF is designed. The magnetic field simulation shows that it is possible to obtain a peak field of 0.6 T on the beam axis at a magnetic gap of 9 mm, with a current density of 800A/mm2 in the superconducting coils. Two coil formers are machined from SAE10¹⁸ stainless steel and coated with TiO2 for insulation. The dimension of the grooves of the coil windings in the coil formers is 5 mm x 10 mm. Formvar insulated NbTi superconducting wires with a diameter of 0.6 mm are used for the 128 turn coils per core groove. A five periods core of NbTi superconducting magnet is machined from SAE1018 stainless steel and winded with copper wires.

WEPWA052	A Gun to Linac Operation Analysis of the Taiwan Light Source Injector	electron, linac, factory, gun	2235
	H.C. Chen, H.H. Chen, S. Fann, S.J. Huang, J.A. Li, C.C. Liang, Y.K. Lin, Y.-C. Liu NSRRC, Hsinchu, Taiwan
	A response surface methodology (RSM) was used to study the gun to linac optimization process of the Taiwan Light Source (TLS) injector at the National Synchrotron Radiation Research Center (NSRRC). A study model, based on artificial neural network (ANN) theory, which uses electron beam tuning knobs as variables, was constructed. An optimization procedure was developed by designating electron beam efficiency as the objective function and the selected beam tuning knobs as the variables. The theoretical model and optimization procedure were both implemented to evaluate the model. By properly applying the constructed optimization procedure, the beam efficiency was improved. This report outlines the details of the gun to linac optimization process experiment.

WEPWO036	Conceptual Design of a Superfluid Superconducting Third Harmonic RF System for the SSRF Storage Ring	cavity, superconducting-cavity, cryogenics, controls	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.

WEPEA001	Simulation Studies of Longitudinal RF-noise and Phase Displacement Acceleration as Driving Mechanism for the MedAustron Synchrotron Slow Extraction	extraction, acceleration, simulation, resonance	2501
	U. Dorda EBG MedAustron, Wr. Neustadt, Austria M. Benedikt, H.O. Schönauer, A. Wastl CERN, Geneva, Switzerland
	MedAustron is a synchrotron based hadron therapy and research facility located in Austria currently entering the installation stage. It is an implementation of the CERN-PIMMS design which proposed induction acceleration by a betatron core as the driving mechanism for the third-order slow resonant extraction. Primarily in order to increase the accelerators flexibility towards future irradiation schemes but also as back-up options, two alternative extraction driving mechanism have been studied: Longitudinal RF-noise and phase displacement acceleration. The advantages as well as the corresponding limitations are explained, analytical estimates and particle tracking results performed with the 2D tracking codes LONG1D and a specifically developed Python based simulation code are presented.

WEPEA010	Modeling Longitudinal Bunched Beam Dynamics in Hadron Synchrotrons using Scaled Fourier-Hermite Expansions	simulation, hadron, controls, 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.

WEPEA011	Bursting Patterns of Coherent Synchrotron Radiation in the ANKA Storage Ring	impedance, radiation, simulation, electron	2516
	M. Schwarz, V. Judin, A.-S. Müller KIT, Karlsruhe, Germany M. Klein SOLEIL, Gif-sur-Yvette, France
	We report measurements of bursting patterns of coherent synchrotron radiation (CSR) for a wide range of single bunch currents at the ANKA storage ring. The radiation was detected with a fast THz detector, a Hot Electron Bolometer, and its signal acquired with both a spectrum analyzer and an external sampling oscilloscope. Both analysis methods consistently show the onset of bursting at a threshold current with the appearance of strong high frequency bands with higher harmonics in the several 10th of kHz range. For currents higher than twice the threshold value an abrupt change in the bursting pattern occurs. These results are compared with different numerical models solving the one-dimensional Vlasov-Fokker-Planck equation.

WEPEA012	Study of Laser Wakefield Accelerators as Injectors for Synchrotron Light Sources	laser, lattice, simulation, storage-ring	2519
	S. Hillenbrand, V. Judin, A.-S. Müller KIT, Karlsruhe, Germany R.W. Aßmann, S. Hillenbrand CERN, Geneva, Switzerland O. Jansen, A.M. Pukhov HHUD, Dusseldorf, Germany
	Short bunch lengths, high beam energies, and small facility footprint make Laser Wakefield Accelerators (LWFA) very interesting as injectors for Synchrotron Light Sources. In this paper, we describe exemplary investigations for the ANKA storage ring.

WEPEA013	Electron Cloud Studies for the Upgrade of the CERN PS	electron, extraction, simulation, proton	2522
	G. Iadarola Naples University Federico II, Science and Technology Pole, Napoli, Italy H. Damerau, S.S. Gilardoni, G. Iadarola, S. Rioja Fuentelsaz, G. Rumolo, G. Sterbini, C. Yin Vallgren CERN, Geneva, Switzerland M.T.F. Pivi SLAC, Menlo Park, California, USA
	The observation of a significant dynamic pressure rise as well as measurements with dedicated detectors indicate that an electron cloud develops in the CERN PS during the last stages of the RF manipulations for the production of LHC type beams, especially with 25ns bunch spacing. Although presently these beams are not degraded by the interaction with the electron cloud, which develops only during few milliseconds before extraction, the question if this effect could degrade the future high intensity and high brightness beams foreseen by the LHC Injectors Upgrade (LIU) project is still open. Therefore several studies are being carried out employing both simulations and measurements with the electron cloud detectors in the machine. The aim is to develop a reliable electron cloud model of the PS vacuum chambers in order to identify possible future limitations and find suitable countermeasures.

WEPEA018	Further Improvement of the PTC-ORBIT Code to Model Realistic Operation of High-beam Power Synchrotrons	injection, resonance, quadrupole, extraction	2534
	A.Y. Molodozhentsev, E. Forest KEK, Ibaraki, Japan
	The combined PTC-ORBIT code has been developed a few years ago to study the dynamics of the high intensity proton beams in synchrotrons, including the nonlinear machine resonances and the space charge effects in the self-consistent manner. In order to extend the code abilities the time variation of the main elements of the synchrotron has been introduced into the PTC module of the code. This feature opens the direct way to model the multi-turn injection process and the slow extraction process by using realistic machine description, in particular the dynamic variation of the betatron tunes, strength of the bump magnets, dynamic resonance correction or resonance excitation. To demonstrate the code abilities the corresponding simulations for CERN PS Booster and for J-PARC Main Ring are discussed.

WEPEA031	Slow extraction design in HIMM	extraction, septum, emittance, resonance	2567
	J. Shi, W.P. Chai, J.W. Xia, J.C. Yang, Y.J. Yuan IMP, Lanzhou, People's Republic of China
	A heavy ion medical machine(HIMM) is proposed for cancer therapy in Lanzhou, China. The slow extraction design of the synchrotron is introduced in this paper. Eight sextupoles are used, four of them are for correcting the chromaticity and the rest for driving the 3rd-order resonance. In order to save the aperture of vacuum chamber, a 3-magnet bump is adopted during the extraction process. The phase space map in the entrance of the electrostatic septum and the last 3 turns' particle trajectory before particle extraction are given.

WEPEA036	Spin Tune Decoherence Effects in Electro- and Magnetostatic Structures	betatron, sextupole, acceleration, emittance	2579
	Y. Senichev, R. Maier, D. Zyuzin FZJ, Jülich, Germany N.V. Kulabukhova St. Petersburg State University, St. Petersburg, Russia
	In Electric Dipole Moment search experiments with polarized beams the coherence of spin oscillations of particles has a crucial role. The decoherent effects arise due to spin tune dependence on particle energy and particle trajectory in focusing-deflecting fields. They are described through the n-th order spin tune aberrations. Since the first order is suppressed by RF field, the second order plays crucial role. It depends on the orbit lengthening and on the odd order field components. We consider the spin decoherence effects and methods of their compensation in different channels, electrostatic, magnetostatic linking the decoherence effects with common characteristics such as the momentum compaction factor, the chromaticity and others.

WEPEA055	Quantitative Evaluation of Trapping and Overall Efficiency for Simple Models in One-degree of Freedom	resonance, simulation, controls, 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.

WEPEA064	SixTrack-Fluka Active Coupling for the Upgrade of the SPS Scrapers	coupling, simulation, injection, luminosity	2657
	A. Mereghetti, F. Cerutti, R. De Maria, B. Goddard, V. Kain, M. Meddahi, O. Mete, Y. Papaphilippou, D. Pastor Sinuela, V. Vlachoudis CERN, Geneva, Switzerland R. Appleby UMAN, Manchester, United Kingdom
	The LHC Injectors Upgrade (LIU) Project aims at upgrading the systems in the LHC injection chain, to reliably deliver the beams required by the High-Luminosity LHC (HL-LHC). Essential for the clean injection into the LHC, the SPS scrapers are one of the important systems under revision. In order to take into account of the effect of betatron and longitudinal beam dynamics on energy deposition patterns, and nuclear and Coulomb scattering in the absorbing medium onto loss patterns, the SixTrack and Fluka codes have been coupled, profiting from the best of the refined physical models they respectively embed. The coupling envisages an active exchange of tracked particles between the two codes at each turn, and an on-line aperture check in SixTrack, in order to estimate the local cleaning inefficiency of the system. Knob-like, time-dependent strengths have been implemented in SixTrack, since the designed scraper system foresees the use of a magnetic bump. The study is intended to assess the robustness of the proposed scraper as well as its effectiveness with respect to the desired performance.

WEPEA073	A 180 MeV Injection Upgrade Design for the ISIS Synchrotron	injection, space-charge, simulation, acceleration	2678
	J.W.G. Thomason, D.J. Adams, B.S. Drumm, D.J.S. Findlay, I.S.K. Gardner, M.C. Hughes, S.J.S. Jago, B. Jones, R.J. Mathieson, S.J. Payne, B.G. Pine, A. Seville, H. V. Smith, C.M. Warsop, R.E. Williamson STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom J. Pasternak STFC/RAL, Chilton, Didcot, Oxon, United Kingdom D.C. Plostinar, C.R. Prior, G.H. Rees STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
	ISIS is the spallation neutron source at the Rutherford Appleton Laboratory in the UK. Obsolescence and reliability issues are motivating plans to replace the present 70 MeV H minus linac, and this paper presents an overview of a design to allow injection of beam into the present ISIS ring at 180 MeV, which would increase intensity as a result of reduced space charge and optimised injection. The key topics addressed are design of the injection straight, injection painting and dynamics, foil specifications, acceleration dynamics, transverse space charge, instabilities, RF beam loading and activation.

WEPFI003	A New Timing System and Electron Gun Modulator	gun, electron, linac, simulation	2705
	A.S. Setty, A.S. Chauchat, D. Fasse, D. Jousse Thales Communications & Security (TCS), Gennevilliers Cedex, France
	In the last decade, Thales Communications & Security has manufactured turnkey linacs for the SOLEIL, ALBA and BESSY II synchrotrons. In the meanwhile, a new timing system and electron gun modulator was designed and a gun pulse length of 600 ps was measured. This paper will describe the system and will present the beam dynamics simulations results, comparing them with those obtained with the previous gun modulator . A. Setty, "Beam dynamics of the 100 MeV preinjector for the Spanish synchrotron ALBA", PAC07, Albuquerque, USA, June 2007.

WEPFI021	Influence of Core Winding Tension and Ribbon Quality on the MA Core RF Characteristics	impedance, vacuum, factory, cavity	2747
	M. Nomura, A. Schnase, T. Shimada, F. Tamura, M. Yamamoto JAEA/J-PARC, Tokai-mura, Japan K. Hara, K. Hasegawa, C. Ohmori, M. Toda, M. Yoshii KEK, Tokai, Ibaraki, Japan
	J-PARC 3 GeV Rapid Cycling Synchrotron (RCS) and Main Ring (MR) employ RF cavities loaded with Magnetic Alloy (MA) cores to generate a high field gradient. To achieve the high field gradient, the core shunt impedance is a key parameter. We found during the development of MA cores for RCS RF cavities that the core shunt impedance was increased by lowering a core winding tension. We lowered the core winding tension in order to improve the electrical insulation between MA ribbon layers. The lower winding tension reduced the core filling factor that is defined as the volume ratio of MA ribbons and geometrical dimensions. The core shunt impedance might be reduced according to the core filling factor reduction. We discuss the reason why the lower winding tension increased the core shunt impedance. We also report the influence of the ribbon quality variation on the MA core RF characteristics.

WEPFI022	Inner Diameter Change over the Years of MA Cores of RF-cavities at the J-PARC 3 GeV Synchrotron	cavity, gun	2750
	T. Shimada, M. Nomura, F. Tamura, M. Yamamoto JAEA/J-PARC, Tokai-mura, Japan K. Hara, K. Hasegawa, C. Ohmori, M. Toda, M. Yoshii KEK, Tokai, Ibaraki, Japan A. Schnase GSI, Darmstadt, Germany H. Suzuki Japan Atomic Energy Agency (JAEA), International Fusion Energy Research Center (IFERC), Rokkasho, Kamikita, Aomori, Japan
	The 11 RF cavities at the J-PARC 3 GeV synchrotron use 198 MA cores. Buckling occurred in some cores since the operation started in October 2007. We have measured the inner diameters of the cores as part of the investigation to determine the cause of buckling when the cavities were disassembled for maintenance. We obtained inner diameter change values of 36 cores over a longer than 2 years interval in the summer of 2012. We noticed deformations of the inner shapes of the cores related to the manufacturing process, and that inner diameter changes over this period were not detected in most of the cores without buckling. Furthermore, an effective core manufacturing process to avoid the buckling has been established. We are going to replace old type cores with new type cores in summer shutdown periods every year and will have finished the replacement work by the summer of 2013. We report the relation between inner shapes of the cores and the manufacturing process and inner shape changes over the years.

WEPFI028	RF System of the CSNS Synchrotron	cavity, controls, LLRF, feedback	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.

WEPFI033	Development of the HLS 40kW Solid State Amplifier	rf-amplifier, power-supply, storage-ring, damping	2777
	L. Lin, G. Huang, C. Li, Y.T. Liu, W. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China
	A 40kW RF Solid State Amplifier (SSA) will replace the 25kW tetrode amplifier as the new RF power generator of HLS 800MeV electron storage ring. This SSA contains sixty-five 650W amplifier units (one unit drives sixty-four’s), with two-stage combination to reach the 40kW output. All of the components of SSA are prepared and tested, each of them meets the design requirements. The SSA has been assembled, and is in off-line testing now. The process of SSA’s design and manufacture, and the test results are presented in this paper.

WEPFI049	CoStub: A 6 1/8” Coaxial Short Circuit using Stubs	cavity, simulation, background, high-voltage	2809
	B. Bravo, F. Mares, F. Pérez CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	ALBA is a 3Gev synchrotron light source located in Barcelona and operating with users since May 2012. The ALBA storage ring uses six room temperature cavities; each one fed by two 80kW IOTs amplifiers at 499.654 MHz. The power of the pair of transmitters is combined by a cavity combiner, CaCo. The two possible operation modes of CaCo at high power have been tested. The symmetrical mode (two IOTs feed the CaCo symmetrically) works properly and without presenting any problem. But in the asymmetrical mode (one IOT feeds the CaCo and the other is keeping passive) a standing wave is created between the passive IOT and Caco, provoking a large voltage in the gap of the passive IOT that broke the ceramic. A new device, CoStub (coaxial stub), to short circuit the coaxial waveguide of the passive arm and protects the passive IOT has been built and successfully tested. This paper presents the design details and the low level and high power test of this device.

WEPFI063	Progress on the ISIS Synchrotron Low Power RF System Upgrade	controls, cavity, 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.

WEPME003	Determination of Optics Transfer between the Kicker and BPMs for Transverse Feedback System	kicker, feedback, betatron, optics	2923
	M. Alhumaidi, A.M. Zoubir TU Darmstadt, Darmstadt, Germany J. Grieser TU Darmstadt, RTR, Darmstadt, Germany
	The knowledge of the transfer optics between the positions of the Kicker and the BPMs is required for the calculation of the correction signal in transverse feedback systems. Therefore, using nominal values of the transfer optics with uncertainties leads to feedback quality degradation, and thus beam disturbances. In this work, we propose a method for measuring the phase advances and amplitude scaling between the positions of the kicker and the BPMs. Directly after applying a kick on the beam by means of the kicker, we record the BPM signals. Consequently, we use the Second-Order Blind Identification (SOBI) algorithm to decompose the noised recorded signals into independent sources mixture. Finally, we determine the required optics parameters by identifying and analyzing the betatron oscillation sourced from the kick based on its mixing and temporal patterns. Results for the heavy ions synchrotron SIS 18 at the GSI are shown.

WEPME004	A Digital Beam-Phase Control System for a Heavy-Ion Synchrotron with a Double-Harmonic Cavity System	controls, cavity, 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

WEPME010	Patient-specific Intensity-modulation of a Slowly Extracted Beam at the HIT Synchrotron	feedback, ion, controls, 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.

WEPME023	Study of the Vibration of the AC Dipole and Magnetic Measurement Girder for CSNS/RCS	dipole, acceleration, resonance, damping	2980
	R.H. Liu, L. Kang, H. Qu, G.Y. Wang, H.J. Wang, J. S. Zhang IHEP, Beijing, People's Republic of China
	The dipole magnet of the China Spallation Neutron Source Rapid-cycling Synchrotron (RCS) will be operated at a 25Hz sinusoidal alternating current which causes severe vibration. The vibration will influence the long-term safety and reliable operation of the magnet. By taking the magnet and magnetic measurement girder as a specific model system, a method for analyzing and studying the dynamic characteristic of the system is put forward by combining theoretical calculation with experimental testing. And the ctive vibration of magnet is different with passive vibration which was causes by ground vibration, so a new isolator was designed to decrease the vibratory force and avoid the resonance phenomenon.

WEPME025	The Surveying Data Processing of Control Network based on HLS Upgrade	controls, survey, 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.

WEPME027	Analysis of Tidal Effects on Measurement Accuracy of HLS	alignment, site, synchrotron-radiation, radiation	2989
	S.F. Xu, X.Y. He, P. Wang, W. Wang, Q.Y. Yao USTC/NSRL, Hefei, Anhui, People's Republic of China
	Funding: Natural Science Foundation of China HLS* is mainly used in survey and high-accuracy alignment in particle accelerator. Monitoring the earth tides is primarily introduced in this paper. Based on the earth tide theory and the ocean load effects on the planet earth, the tidal effects on a hydrostatic leveling system is analyzed. Finally, the local ground deformation is obtained,and the current research establish a foundation for the further study. HLS-hydrostatic levelling system

WEPME033	Status of SSRF Fast Orbit Feedback System	feedback, EPICS, power-supply, controls	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.

WEPME048	Adjusting and Calibration Method for TPS Laser PSD System	laser, alignment, factory, storage-ring	3037
	M.L. Chen, J.-R. 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, M.H. Wu NSRRC, Hsinchu, Taiwan J.-R. Chen National Tsing Hua University, Hsinchu, Taiwan
	Laser PSD positioning system is a part of the TPS girder auto-alignment system and is designed for aligning and positioning the straight-section girders of TPS storage ring. Although the components of Laser PSD system are fabricated, assembling and adjusting precisely in advance, the accuracy of Laser PSD system is still influenced by girder fabricating quality, assembling errors and moving errors by transportation. For system correction, Laser beam positions on four sets of PSDs are formulized as an equation and calibrated with Laser tracker ultimately. According to the PSD calibration formula, the two girders of 18m long straight-section can be aligned and positioned within 20um by comparing with Laser tracker. This paper describes the assembly, installation and calibration process of Laser PSD system.

WEPME055	Investigation of Source Point Instabilities in Dipole Magnet Based Beamlines	dipole, feedback, optics, radiation	3055
	M. Apollonio, R. Bartolini Diamond, Oxfordshire, United Kingdom R. Bartolini JAI, Oxford, United Kingdom
	At Diamond the source point in the second dipole of the Double Bend Achromats can vary due the lack of adjacent BPMs constraining angle and position of the electron beam at the dipole. We have implemented a code based on our AT model to predict the effects of a corrector strength change and compared our predictions to data both from a beamline and from our pinhole cameras. We discuss the possibility of interfacing the code to a ray tracing routine in order to infer beam spot changes in the downstream beamline and suggest a procedure to restore the original source point.

THXB101	High Power Operation and Beam Instrumentations in J-PARC Synchrotrons	extraction, beam-losses, quadrupole, proton	3085
	T. Toyama J-PARC, KEK & JAEA, Ibaraki-ken, Japan
	Beam monitors developed and utilized at MR and RCS of J-PARC will be presented with emphasis on special characteristics for high intensity proton accelerator. Achieved beam characteristics and approach to improve beam intensity will be described in connection with the beam monitors. Usage of a transverse RF field to improve a duty factor of the slow extracted beam will be presented.
	Slides THXB101 [16.387 MB]

THXB201	Novel Techniques and Challenges in Hadron Therapy	ion, proton, cyclotron, extraction	3112
	Th. Haberer, E. Feldmeier, M. Galonska, A. Peters, C. Schömers HIT, Heidelberg, Germany
	This talk should review novel techniques and challenges for beam delivery systems with various beam scanning methods (such as 3D scanning, 4D scanning and so on) to conform the beam dose to the tumor shape in proton and carbon ion therapy, as developed by PSI, GSI, HIMAC, IMP etc. Besides traditional accelerators such as cyclotrons and synchrotrons, the talk should review the technical challenges and prospects for future compact hadron therapy accelerators such as DWA, laser accelerators and so on.
	Slides THXB201 [4.934 MB]

THPPA03	The Development of China’s Accelerators I Have Experienced	proton, luminosity, linac, radiation	3144
	S.X. Fang IHEP, Beijing, People's Republic of China
	The development of China’s high energy accelerator for half a century falls into two stages, namely the first 20 hovering years (1958-1978) and the later 30 years of rapid development (from 1978 till now). I was lucky enough to have experienced the whole process, witnessed, and to some extent, joined in the decision-making, the projects approval, the designing, the development and construction of China's five large scientific facilities undertaken by the Institute of High Energy Physics in Beijing. A brief review is given of the previous stage of history regarding the consideration of China’s high energy accelerators in the first 20 years. A short presentation is also given of the later 30 years concerning the rapid development of the Beijing Electron-Positron Collider (BEPC and BEPCII), the completed BEPC-based Shanghai Synchrotron Radiation Facility (SSRF), the Chinese Spallation Neutron Source (CSNS) under construction, the high-intensity proton accelerator (ADS) used for nuclear waste transmutation and the proton therapy machine in the R&D stage.
	Slides THPPA03 [6.015 MB]

THPEA002	The Accelerator Control System at ELSA	controls, diagnostics, electron, 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	controls, 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.

THPEA015	Induced Radioactivity Research for Scraper	electron, radioactivity, linac, radiation	3173
	L.J. He, Y.K. Chen, W. Li USTC/NSRL, Hefei, Anhui, People's Republic of China
	The 200MeV electron linac of NSRL is one of the earliest high-energy electron linear accelerators in China. The electrons are accelerated to 200MeV by five accelerating tubes and collimated by the scraper followed each accelerating tube. The scraper aperture is smaller than the accelerating tube,so some electrons will hit on the structure materials when they pass through them. These lost electrons will cause induced radioactivity due to bremsstrahlung, cascade shower and photo-nuclear reaction. This paper gives the simulation to different energy electrons lost at the corresponding scraper by EGSnrc. The results showed that electrons were lost mainly at the scraper during the accelerating period,and the actual measurement confirmed this. Meanwhile,the induced radionuclide types have been studied. Recently,the linac mentioned above has been retired because of upgrading. The equipments and materials removed are used to study induced radioactivity generated in different materials. The research will provide the theoretical basis for the similar accelerator decommissioning plan,and is also significant for accelerator structure design,material selection and radiation protection programs design.

THPEA041	Performance Improvements of the SPS Internal Beam Dump for the HL-LHC Beam	kicker, vacuum, proton, dumping	3231
	F.M. Velotti, O. Aberle, C. Bracco, E. Carlier, P. Chiggiato, J.A. Ferreira Somoza, B. Goddard, M. Meddahi, V. Senaj, J.A. Uythoven CERN, Geneva, Switzerland
	The SPS internal beam dump has been designed for beam specifications well below the HL-LHC ones, and for modes of operation which may not be adequate for the HL-LHC era. The present system suffers from several limitations in the allowed intensity and energy range, and its vacuum performance affects nearby high-voltage kicker systems. In this report the limitations of the internal beam dump system are reviewed, and the possible improvements compared. Preliminary upgrade proposals are presented, taking into consideration the expected operational HL-LHC parameters.

THPEA046	Machine Protection at the LHC - Experience of Three Years Running and Outlook for Operation at Nominal Energy	injection, feedback, extraction, optics	3246
	D. Wollmann, R. Schmidt, J. Wenninger, M. Zerlauth CERN, Geneva, Switzerland
	With above 22fb-1 integrated luminosity delivered to the experiments ATLAS and CMS the LHC surpassed the results of 2011 by more than a factor 5. This was achieved at 4TeV, with intensities of ~2e14p per beam. The uncontrolled loss of only a small fraction of the stored beam is sufficient to damage parts of the sc. magnet system, accelerator equipment or the particle physics experiments. To protect against this a correct functioning of the complex LHC machine protection (MP) systems through the operational cycle is essential. Operating with up to 140MJ stored beam energy was only possible due to the experience and confidence gained in the two previous running periods, where the intensity was slowly increased. In this paper the 2012 performance of the MP systems is discussed. The strategy applied for a fast, but safe, intensity ramp up and the monitoring of the MP systems during stable running periods are presented. Weaknesses in the reliability of the MP systems, set-up procedures and setting adjustments for machine development periods, discovered in 2012, are critically reviewed and improvements for the LHC operation after the up-coming long shut-down of the LHC are proposed.

THPEA049	Implementation of the EPICS Data Archive System for the TPS Project	EPICS, controls, GUI, 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.

THPFI014	Bellows with a New RF Shield Made of Metal Braid for High Intensity Proton Accelerators	impedance, vacuum, background, coupling	3321
	N. Ogiwara, J. Kamiya, M. Kinsho, Y. Shobuda JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan O. Koizumi Sun-Tech limited, Kobe, Japan
	In the 3 GeV-RCS (Rapid cycling Synchrotron) in J-PARC (Japan Accelerator Research Complex) project, large-scale hydro-formed bellows were developed to adjust the gap between the ceramic ducts and/or between the ceramic ducts and the transport ducts. They have been equipped with a newly developed RF shield, because the usual beryllium-copper spring finger contacts were found to be very hard (roughly 1000 N/mm) owing to the large size. This contact is made of Ti braid, which consists of wires with a diameter of 0.3 mm. This RF contact is a kind of basket (with two ports) made with the braids. Because of the spring effect, the contact can change shape easily. In addition, the contact can easily connect the different cross sections in a smooth fashion. Furthermore, this structure is almost free from the dust generation, which is one of the most troublesome problems for the usual spring finger contacts. This time, we have constructed reserve bellows with the RF shield made of SUS 316L wires to improve the reliability of user operation. The outline of the bellows will be presented, especially laying emphasis on the mechanical function of the RF shield.

THPFI016	DESIGN CONSIDERATION OF BEAM DUCTS FOR QUADRUPOLE CORRECTORS IN J-PARC RCS	quadrupole, vacuum, injection, focusing	3327
	J. Kamiya, N. Hayashi, H. Hotchi, M. Kinsho, N. Ogiwara, N. Tani, Y. Watanabe JAEA/J-PARC, Tokai-mura, Japan
	which rapidly correct the tunes, are planned to be installed during the summer shutdown in 2013. The characteristic of the excitation pattern of such quadrupoles (quadrupole corrector) is their fast change of magnetic field, which are more than 200T/s at the fastest point. In this report, we describe a deliberation flow about the design of a vacuum chamber, which is installed in the quadrupole corrector. The effect of eddy current was calculated in the case of the current titanium vacuum chamber. The results showed that the temperature rise was too much (up to ~350oC) and the magnetic field in the vacuum chamber is largely distorted by the eddy current. Therefore we decided to employ an alumina ceramics vacuum chamber, for which we have a past achievement in RCS. We estimated the displacement and stress, which is caused by the atmospheric pressure, for the alumina ceramics vacuum chamber and vacuum component around it by making the calculation model for the finite element method. It was found that there was no large displacement and stress by installing the alumina ceramics vacuum chamber. M. Kinsho, et al. Vacuum 81 (2007) 808.

THPFI024	Application of Electropolishing in CSNS/RCS Primary Collimator Scrapers	cathode, collimation, proton, scattering	3348
	L. Kang, Z.X. He, H. Qu, J.B. Yu, Y.Q. Zou IHEP, Beijing, People's Republic of China
	According to the requirements for the beam collimation system physical design of the rapid cycling synchrotron (RCS) of China Spallation Neutron Source (CSNS) , the primary collimator scrapers are made of 0.17±0.005mm thickness tungsten sheets. The machining of the tungsten sheet is very difficult because of high hardness and characteristics of the intrinsic brittleness of tungsten. In this paper, electropolishing processing methods is used for tungsten sheets processing. A special electropolishing device is designed according to the principle and process of electropolishing. The processing of tungsten sheets are finally completed after a series of experiments. And the rules of electropolishing for tungsten sheet processing are obtained according to the experimental results.

THPFI031	Development of Beam Collimators for the 1.6 GeV Rapid Cycling Synchrotron of CSNS	collimation, vacuum, simulation, shielding	3364
	J.B. Yu, pf.He. He, L. Kang, H. Qu, Y.Q. Zou IHEP, Beijing, People's Republic of China
	In order to reduce the uncontrolled losses in the localized station, the beam collimation system has been performed for the 1.6GeV synchrotron of CSNS. The CSNS/RCS transverse collimation system is designed to be a two-stage system which consists of one primary collimator and four secondary collimators. Much work about machinery design and manufacture of the collimation system has been done till now. This paper will show the exterior frame of collimation system by considering the physical demands and spatial position. Then the progress which contains design and machining of collimators will also be introduced. Finally some problems which are mainly about the design of secondary collimators will be mentioned.

THPFI044	NEG Thin Film Coating Development for the MAX IV Vacuum System	vacuum, cathode, plasma, synchrotron-radiation	3385
	M.J. Grabski, J. Ahlbäck, E. Al-Dmour, P.F. Tavares MAX-lab, Lund, Sweden S. Calatroni, P. Chiggiato, P. Costa Pinto, M. Taborelli CERN, Geneva, Switzerland
	The new synchrotron radiation facility of the MAX IV laboratories is under construction and expected to deliver the first light beam in 2016. To cope with the small aperture, the intense photon bombardment and the low-pressure requirement, most of the beam pipes for the 3-GeV ring are going to be coated with Ti-Zr-V non-evaporable getter (NEG) thin films. To take advantage from the experience acquired during the construction of the Large Hadron Collider (LHC), collaboration between CERN and MAX IV Laboratories has been set up. The choice of the extruded Cu tubes, the preliminary surface treatments, the coating configuration, and the performance validation of the small-diameter vacuum chambers have been addressed. In parallel, an intense development has been tackled at CERN for the coating of vacuum chambers where photon and electron beams circulate in separate pipes. The most important results of the collaboration are presented and future perspectives pointed out.

THPFI066	Performance Enhancement of Electrical Power System at NSRRC	controls, radio-frequency, 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, controls, booster, status	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	controls, 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, controls, photon, PLC	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.

THPFI072	Heat Transfer Analysis of a Water-cooled Channel for the TPS Front End Components	simulation, synchrotron-radiation, radiation, insertion	3466
	C.K. Kuan, J.-R. Chen, Y.T. Cheng, J.Y. Chuang, H.Y. Lin, P.A. Lin, Y.K. Liu, I.C. Sheng, T.C. Tseng NSRRC, Hsinchu, Taiwan J.-R. Chen National Tsing Hua University, Hsinchu, Taiwan
	The masks, absorbers and slits must withstand the extremely high power and power density in the TPS front end. The material always used is OFHC or Glidcop. One solution is to increase the cooling efficiency of the water-cooled channel in these components. With the restrictions of water pressure < 7 kg/cm² and water flow velocity < 3 m/s, the wire coil is chosen to enhance the average heat- transfer coefficient and increase not too much the loss of water pressure. With a water channel of diameter 7.5 mm and wire coil inserts of pitch 7.5 mm and wire diameter 1 mm, the cooling efficiency becomes enhanced 1.4 to 2 times in the components of the TPS front end. The wire coils of varied pitches are simulated and calculated in this work. We also compare our investigated data with other experimental data of other authors.

THPFI075	Baking Test for an In-vacuum Undulator	vacuum, undulator, controls, 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.

THPFI079	Start-up of the NESTOR Facility Vacuum System	vacuum, storage-ring, electron, ion	3478
	A.Y. Zelinsky, A.N. Gordienko, V.A. Grevtsev, I.I. Karnaukhov, I.M. Karnaukhov, N.I. Mocheshnikov, A. Mytsykov, V.L. Skirda NSC/KIPT, Kharkov, Ukraine
	The Kharkov X-ray generator NESTOR based on Compton backscattering is under commissioning. The vacuum system of the complex integrates a linear accelerator-injector, the beam transport channel and the electron storage ring with energy range from 40 to 225 MeV. Elements of vacuum chambers, pumping facilities, cleaning surfaces procedures are described. Chambers are made of stainless steel (SS). After vacuum pretesting pressure 5 × 10^-9 Torr in the storage chambers ring achieved.

THPME001	Permanent Magnets in Accelerators can save Energy, Space, and Cost	permanent-magnet, dipole, quadrupole, vacuum	3511
	F. Bødker, L.O. Baandrup, A. Baurichter, N. Hauge, K.F. Laurberg, B.R. Nielsen, G. Nielsen Danfysik A/S, Taastrup, Denmark O. Balling Aarhus University, Aarhus, Denmark F.B. Bendixen, P. Kjeldsteen, P. Valler Sintex A/S, Hobro, Denmark S.P. Møller, H.D. Thomsen ISA, Aarhus, Denmark H.-A. Synal ETH, Zurich, Switzerland
	Green Magnet technology with close to zero electrical power consumption without the need for cooling water saves costs, space and hence spares natural resources. A compact dipole based on permanent magnets has been developed at Danfysik in collaboration with Sintex and Aarhus University. This first Green Magnet has been delivered to ETH Zurich for testing in a compact accelerator mass spectrometer facility. Permanent NdFeB magnets generate a fixed magnetic field of 0.43 T at a gap of 38.5 mm without using electrical power in the H-type 90° bending magnet with a bending radius of 250 mm. Thermal drift of the permanent magnets is passively compensated. Small air cooled trim coils permit fine tuning of the magnetic field. Magnetic field measurements and thermal stability tests show that the Green Magnet fully meets the magnetic requirements of the previously used electromagnet. The use of Green Magnet technology in other accelerator systems like synchrotron light sources is discussed.

THPME003	Standard Sextupole Magnets for NSLS-II Synchrotron	sextupole, dipole, booster, target	3517
	C.W.O. Ostenfeld, N. Hauge, P. Ladefoged Danfysik A/S, Taastrup, Denmark
	Danfysik received the order to design, manufacture and test 169 Standard Sextupole Magnets for the NSLS-2 synchrotron. Extraordinary tight tolerances were specified for the mechanical and magnetic properties. We present a re-optimized magnetic pole profile to make a more mechanically robust design, suitable for large-scale manufacture. Due to a well-controlled wire erosion process during the manufacturing stage, the mechanical tolerances were kept on the 10 micron level, even after assembly/disassembly cycles. A major challenge of the project was to verify the magnetic performance of the magnets. This was done using our in-house harmonic measurement bench. We present magnetic measurements of the magnet series, measured over more than 24 months, which show high stability, both in terms of magnetic roll angle, error field terms, and integrated strength.

THPME021	Application of Magnetic Field Integral Measurement of Magnet Module to Research Alterable Gap Undulator	multipole, controls, undulator, quadrupole	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.

THPME039	The Control System for the Purification Station at NSRRC	cryogenics, controls, monitoring, vacuum	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.

THPWO056	A 5.3 MeV/U, 200MHz APF DTL for Carbon Ions as an Injector of Medical Synchrotron	focusing, cavity, emittance, DTL	3890
	P. Jiang, Y.J. Yuan IMP, Lanzhou, People's Republic of China
	A new low energy medium frequency DTL for 12C⁵⁺ with alternative phase focusing method (APF), which has advantage in compact space and low cost, was designed as an injector of medical synchrotron. There is no conventional focusing elements in the APF DTL, and transversal focusing is realized using RF field by varying synchronous phase instead. The envelopes of beam size are presented and the emittance change of six-dimension phase space is shown. The simple method proposed by Y. Iwata was used to create synchronous phase array. Since the motion between transversal and longitudinal plains are coupled, the longitudinal acceptance of the DTL is not large.

FRYAA01	An Overview of Light Source Development in Asia	FEL, radiation, electron, linac	4005
	D. Wang SINAP, Shanghai, People's Republic of China
	This talk should cover the history of light sources that have been constructed, are now in operation or planned for the future in Asia. Advances in accelerator physics and technological innovations leading to steadily increasing machine performance and photon beam properties should be discussed.
	Slides FRYAA01 [7.342 MB]

Paper

Title

Other Keywords

Page

MOODB101

Manufacturing of the First of Series SIS100 Dipole Magnet

dipole, instrumentation, magnet-design, laser

31

St. Sattler, W. Gärtner, Dr. Scheller, R. Schönbein, W. Walter
BNG, Würzburg, Germany
E.S. Fischer, J.P. Meier, H. Müller, P. Schnizer
GSI, Darmstadt, Germany

Babcock Noell (Würzburg, Germany) manufactures the First of Series (FOS) SIS100 dipole magnet for the FAIR project. This contribution reports on the progress during the design-phase, performed together with GSI, and on the manufacturing- and assembly-processes. Special emphasis will be given on new or special techniques adopted to fulfill the stringent requirements demanded by such a magnet. The new tooling systems and machines which were developed and brought into operation for this FOS magnet will be discussed.

MOODB103

Results of an Experiment on Hydrodynamic Tunnelling at the SPS HiRadMat High Intensity Proton Facility

target, simulation, proton, instrumentation

37

R. Schmidt, J. Blanco, F. Burkart, D. Grenier, D. Wollmann
CERN, Geneva, Switzerland
E. Griesmayer
CIVIDEC Instrumentation, Wien, Austria
N.A. Tahir
GSI, Darmstadt, Germany

To predict the damage for a catastrophic failure of the protections systems for the LHC when operating with beams storing 362 MJ, simulation studies of the impact of an LHC beam on targets were performed. Firstly, the energy deposition of the first bunches in a target with FLUKA is calculated. The effect of the energy deposition on the target is then calculated with a hydrodynamic code, BIG2. The impact of only a few bunches leads to a change of target density. The calculations are done iteratively in several steps and show that such beam can tunnel up to 30-35 m into a target. Validation experiments for these calculations at LHC are not possible, therefore experiments were suggested for the CERN Super Proton Synchrotron (SPS), since simulation studies with the tools used for the LHC also predict hydrodynamic tunnelling for SPS beams. An experiment at the SPS-HiRadMat facility (High-Radiation to Materials) using the 440 GeV beam with 144 bunches was performed in July 2012. In this paper we compare the results of this experiment with our calculations of hydrodynamic tunnelling.

Slides MOODB103 [40.426 MB]

MOPEA001

Status of the Australian Synchrotron Top-Up Operations

injection, storage-ring, linac, diagnostics

58

M.J. Boland, R.T. Dowd, G. LeBlanc, D.C. McGilvery, D. Morris, Y.E. Tan, J. Trewhella, D. Zhu, E.D. van Garderen
ASCo, Clayton, Victoria, Australia

In May 2012 the Australian Synchrotron commenced Top-Up Operations for User beamtime. The facility was designed for top-up from the start with a full energy 3 GeV injection system, however top-up only became a priority once the beamline user community had established itself at the new facility in operation since April 2007. New beam diagnostic and equipment protections systems were implemented as part of the move to top-up, including a new injection efficiency monitoring system. The effect of top-up on the beamline data was also tested with each beamline prior to engaging top-up during user runs. Top-up has now been running successfully for one year and the performance statistics from this period will be presented. Top-up operations is a very popular standard mode for user beam and falling into decay mode is now treated almost as a beam dump.

MOPEA002

1.5 GeV Low Energy Mode for the Australian Synchrotron

storage-ring, booster, extraction, injection

61

R. Clarken, M.J. Boland, Y.E. Tan
ASCo, Clayton, Victoria, Australia
J.S. Hughes, K.P. Wootton
The University of Melbourne, Melbourne, Australia

The Australian Synchrotron injection system and storage ring have been retuned to 1.5 GeV for use in special operations and machine development modes. The systems were designed for 3 GeV user operations but for certain research a lower energy of 1.5 GeV is advantageous. A description of how the new low energy mode was achieved is given, including extraction on the fly from the booster synchrotron and scaling of the storage ring lattice.

MOPEA004

Beam Lifetime in the ASTRID and ASTRID2 Synchrotron Light Sources: Excitations and Vacuum Dependences

vacuum, ion, emittance, electron

67

J.S. Nielsen, N. Hertel, S.P. Møller
ISA, Aarhus, Denmark

The beam lifetime is a very important parameter for synchrotron light sources without top-up, and sometimes more important than the lowest possible vertical beam emittance. At the ASTRID synchrotron light source, we have for many years routinely applied a phase modulation of the accelerating RF field, together with a vertical excitation of the beam at the first vertical betatron frequency. These two effects increase the beam lifetime from about 3 hours to more than 100 hours at 150 mA. Lifetime measurements as function of modulation and excitation parameters will be presented. Additionally, measurements of the beam lifetime in ASTRID and ASTRID2 as function of vacuum pressure will be presented.

MOPEA019

Studies of Bunch-bunch Interactions in the ANKA Storage Ring with Coherent Synchrotron Radiation using an Ultra-fast Terahertz Detection System

radiation, storage-ring, wakefield, synchrotron-radiation

109

A.-S. Müller, B.M. Balzer, C.M. Caselle, N. Hiller, M. Hofherr, K.S. Ilin, V. Judin, B. Kehrer, S. Marsching, S. Naknaimueang, M.J. Nasse, J. Raasch, A. Scheuring, M. Schuh, M. Schwarz, M. Siegel, N.J. Smale, J.L. Steinmann, P. Thoma, M. Weber, S. Wuensch
KIT, Karlsruhe, Germany

Funding: Supported by Initiative and Networking Fund of the Helmholtz Association under contract No. VH-NG-320 and German Federal Ministry of Education and Research under Grant. Noss. 05K10VKC and 05K2010VKD
In the low-alpha operation mode of the ANKA synchrotron light source, coherent synchrotron radiation (CSR) is emitted from short electron bunches. Depending on the bunch current, the radiation shows bursts of high intensity. These bursts of high intensity THz radiation display a time evolution which can be observed only on long time scales with respect to the revolution period. In addition, long range wake fields can introduce a correlation between the bunches within a bunch train and thus modify the observed behavior. A novel detection system consisting of an ultra-fast superconducting THz detector and data acquisition system was used to investigate correlations visible on the bursting pattern and to study the interactions of very short pulses in the ANKA storage ring.

MOPEA020

Comparison of Different Approaches to Determine the Bursting Threshold at ANKA

radiation, storage-ring, electron, synchrotron-radiation

112

P. Schönfeldt, N. Hiller, V. Judin, A.-S. Müller, M. Schwarz, J.L. Steinmann
KIT, Karlsruhe, Germany

The synchrotron light source ANKA at the Karlsruhe Institute of Technology provides a dedicated low-α-optics. In this mode bursting of Coherent Synchrotron Radiation (CSR) is observed for bunch charges above a threshold that depends on beam parameters. This threshold can be determined by several approaches, e.g. bunch lengthening or changes in the THz radiation spectra. This paper compares different methods and their implementation at the ANKA storage ring outlining their advantages, disadvantages and limitations, including reliability and possibility of real time analysis.

MOPEA026

X-ray Powder Diffraction Beamline for the Iranian Light Source Facility

photon, electron, focusing, brilliance

130

H. Khosroabadi, S. Amiri, H. Ghasem, A. Gholampour
ILSF, Tehran, Iran
H. Ghasem
IPM, Tehran, Iran

Iranian Light Source Facility (ILSF) project has been initiated since 2010 in order to design and construction of a synchrotron facility in Iran. In parallel with the machine’s activities, scientific committee, users community and beamline technical group are working on different aspects of the scientific and beamline design issues for the operating phase after construction*. X-ray powder diffraction beamline is one of the most priorities in ILSF due to wide range of applications and big potential user community in Iran. Conceptual design report of this beamline operating in other worldwide synchrotrons have been studied and compared in details. The light source and schematic design of the beamline has been prepared in this study. Then, the parameters have been calculated and have been optimized by employing computational software such as XOP and SHADOW**. The optical properties of the optical elements such as reflectivity, absorbance, Bragg diffraction, rocking curve, aberration, etc have been studied at this design, and the results have been compared with the other published results. The outcome and final results of this design progress will be discussed in details.
References:
* Conceptual Design Report (2011, summer), ILSF, http://ilsf.ipm.ac.ir/.
** http://www.esrf.eu/UsersAndScience/Experiments/TBS/SciSoft/xop2.3.

MOPEA033

Status of Upgrade Project of the 1.2 GeV Booster Synchrotron at Tohoku University

booster, quadrupole, alignment, dipole

151

F. Hinode, H. Hama, S. Kashiwagi, T. Muto, I. Nagasawa, K. Nanbu, Y. Shibasaki, K. Takahashi
Tohoku University, Research Center for Electron Photon Science, Sendai, Japan

The 1.2 GeV electron synchrotron has been operated for nuclear physics experiment since 1997 in Electron Light Science Centre, Tohoku University, in which the high energy gamma-rays via bremsstrahlung has been supplied for hadron physics. After the Great East Japan Earthquake in March 2011, recovery and reconstruction work of the accelerator complex is in progress vigorously. While the compact 90 MeV linac is newly constructed as the dedicated injector for the synchrotron, old power supplies of synchrotron magnets and also pulsed magnets for beam injection are going to be replaced in the synchrotron. Furthermore replacements of some quadrupole magnets to the combined function magnets with sextupole component are also on going. Modifying the ring optics so as to introduce the horizontal dispersion on the combined magnet position, this replacement work will make it possible to correct the chromaticity. At the present, power supplies and combined magnets have been manufactured and those installations will be completed soon. We will present the current status of upgrade project of the booster synchrotron.

MOPEA044

Maintenance Experience for Personnel Safety System at SSRF

controls, PLC, radiation, 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.

MOPEA072

Recent Improvement of the APS Booster Synchrotron

booster, lattice, emittance, injection

252

C. Yao, R. Laird, V. Sajaev, N. Sereno, H. Shang, J. Wang, S. Xu
ANL, Argonne, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-ACO2-O6CH11357.
The APS booster injector is a 7-GeV electron synchrotron. Several improvements have been implemented in the booster area, including the development of the 92-nm low emittance lattice, upgrading the ramp current readback ADC, and development of a new firing card for the main ramp supplies. Recently we have completed the commissioning of the low emittance lattice and it is now APS operational lattice. Combined with improvement in the optimization in the storage ring lattice and injection, we have achieved close to 100% storage ring injection efficiency. This report presents the improvements and measured beam parameters and the measured performance of the ramp control.

MOPFI007

SIS-18 RF Knock-Out Optimization Studies

extraction, resonance, dipole, septum

297

M.M. Kirk, D. Ondreka, P.J. Spiller
GSI, Darmstadt, Germany

The extraction efficiency and spill temporal-structure of the SIS-18 heavy ion synchrotron are part of the upgrades to the GSI accelerator complex. Losses to the extraction septum can be minimised through implementation of the Hardt condition resulting however in a poorer quality of the spill microstructure at resolutions of a few microseconds due to lowering of the horizontal chromaticity from its 'natural' value. Ways to improve the extraction efficiency and spill microstructure are investigated with a tracking code. One possibility for improvement may be to use an alternative RF modulation applied to the knock-out exciter.

MOPFI010

Initial Beam Loss and Control of Dynamic Vacuum Effects in SIS18

injection, ion, collimation, vacuum

300

Y. El-Hayek
FIAS, Frankfurt am Main, Germany
M.M. Kirk, D. Ondreka, P.J. Spiller
GSI, Darmstadt, Germany
U. Ratzinger
IAP, Frankfurt am Main, Germany

To stabilize the dynamic pressure in the SIS18, the systematic initial beam loss must be minimized. Beam Particles, which are lost on the vaccum chamber cause a local pressure increase. Thereby the collision rate between beam ions and residual gas particles and consequently beam loss by ionization is enhanced. The reduction and control of beam loss in the injection channel, during multiturn injection and during the Rf capture process has an outstanding importance for the vacuum dynamics. One way to minimize the initial losses in the synchrotron is to displace the beam loss into the transfer channel (TK) between UNILAC and SIS. In the transfer channel, the beam edges are trimmed by means of a collimator system and a sharply defined phase space area can be injected into SIS18. The effect of reduced initial beam loss on the vaccum dynamics is presented.

MOPFI030

Study of the Beam Injection and Extraction of the Proton Irradiation Accelerator

injection, proton, extraction, kicker

348

Y.W. An, H.F. Ji, S. Wang
IHEP, Beijing, People's Republic of China

The proton irradiation accelerator is widely founded for industry application, and the extracted beam is required to have large intensity as a pulse beam or uniform distribution for scanning. A multi-turn injection is adopted and the proton beam is injected into the ring with the energy of 10MeV. In order to increase injection beam intensity, local bump orbit including two-bump, three-bump and four-bump is well studied and optimized, and the septum magnet thickness and localization are also studied for an effective injection. A RF knock-out method is used for slow extraction due to the fast response character. In order to decrease the global spill, double RF kicker and the control of the aptitude modulation (AM) function of the transverse RF field are well studied.

MOPFI046

Transverse RF Kicker Excitation and Longitudinal RF Noise Diffusion for Slow Extraction from SAPT

extraction, kicker, simulation, resonance

386

L. Ouyang, M. Gu, D.M. Li, Q. Yuan, M.Z. Zhang
SINAP, Shanghai, People's Republic of China

Two key techniques used in the slow extraction from synchrotron accelerator: longitudinal RF stochastic noise acceleration, and transverse RF knock out excitation have been studied in this paper. Detailed comparison have revealed the potentials and limits of both methods. For the longitudinal RF stochastic acceleration excitation, the focus has been the phase space compression of particles, which makes the them to hasten around the RF bucket of the cavity, thus to lower the senstivity to ripple. For the transverse RF knock out excitation, the emphasis have been optimal schemes of amplitude modulation and frequency modulation of the RF singals. The optimizations are also used to lower the senstivity of the beam to the ripple and to enhance the uniformity of the extracted beam.

MOPFI063

Progress on Designs for 180 MeV Injection into the ISIS Synchrotron

injection, dipole, septum, stripper

428

B. Jones, D.J. Adams, B.S. Drumm, M.C. Hughes, A.J. McFarland, C.M. Warsop
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom

The ISIS Facility at the Rutherford Appleton Laboratory in the UK produces intense neutron and muon beams for condensed matter research. It operates at 50Hz accelerating beam via a 70 MeV H⁻ linac and an 800 MeV proton synchrotron, delivering a mean beam power of 0.2 MW. As an initial step towards megawatt operations at ISIS, a study of replacement of the existing injector with a new 180 MeV H⁻ linac has recently been completed. This could enable an increase in beam power to approximately 0.5 MW. The ISIS Facility at the Rutherford Appleton Laboratory in the UK produces intense neutron and muon beams for condensed matter research. It accelerates 3×10¹³ protons per pulse (ppp) at 50 Hz through a 70 MeV H− linac and an 800 MeV proton synchrotron, delivering a mean beam power of ~0.2 MW. A favoured first step to upgrade ISIS towards the megawatt regime is replacement of the linac with a new 180 MeV injector described in [1]. Studies of this upgrade, which aims to increase mean beam power up to 0.5 MW are outlined in [2]. This paper reports on recent development of the designs including the injection septum, dipole power supplies and detailed tracking of partially stripped foil products.

MOPME007

High Resolution Synchrotron Light Analysis at ELSA

diagnostics, vacuum, optics, electron

482

S. Zander, F. Frommberger, P. Hänisch, W. Hillert, M.T. Switka
ELSA, Bonn, Germany

Funding: Funded by the DFG within the SFB/ TR 16
The Electron Stretcher Facility ELSA provides polarized electrons with energies up to 3.5 GeV for external hadron experiments. In order to suffice the need of stored beam intensities towards 200 mA, advanced beam instability studies need to be carried out. An external diagnostic beamline for synchrotron light analysis has been set up and provides the space for multiple diagnostic tools including a streak camera with time resolution of < 1 ps. Beam profile measurements are expected to identify instabilities and reveal their thresholds. The effect of adequate countermeasures is subject to analysis. The current status of the beamline development will be presented.

MOPME023

ORBIT Beam Simulation Progress in the 3-GeV Rapid Cycling Synchrotron of J-PARC

simulation, lattice, injection, impedance

521

P.K. Saha, H. Harada, H. Hotchi, Y. Shobuda, M. Yamamoto
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
J.A. Holmes
ORNL, Oak Ridge, Tennessee, USA
S. Kato
Tohoku University, Graduate School of Science, Sendai, Japan

We have made a numerous progress for beam simulation in the 3-GeV RCS (Rapid Cycling Synchrotron) of J-PARC (Japan Proton Accelerator Research Complex) by using 3-D particle tracking code, ORBIT. Namely, the TEAPOT lattice file used for ORBIT tracking has been made to give exactly same results to that with SAD model used for the RCS beam commissioning. In addition, time dependent lattice functions of the injection chicane magnets and similar other time dependent lattice imperfections, which are already found to have significant influences on the beam losses in the real machine have also been successfully introduced. At present, time dependent transverse and longitudinal impedances are going to be introduced. That should prove the ORBIT code much more matured for beam simulations in synchrotrons. Latest beam simulation results illustrating these new realistic features are presented.

MOPME039

A New Method of Acquiring Fast Beam Transversal Profile in the Storage Ring

factory, electron, synchrotron-radiation, simulation

556

C. Cheng, P. Lu, B.G. Sun, K. Tang, F.F. Wu, Y.Y. Xiao, Y.L. Yang, Z.R. Zhou, J.Y. Zou
USTC/NSRL, Hefei, Anhui, People's Republic of China

A new method of acquiring fast beam transverse profile has been developed and will be used in HLS II. This method is based on four signals from MAPMT (multi-anode photo-multiplier tube) and logarithm processing technique. First, the calculation formula of beam transversal size and position are deduced using above method. Then, the main performances (e.g. sensitivity and linearity range) are analyzed. According to stimulation result, regardless of cross-talk and inconsistency between channels, the size signal has a linear relation with size s when s=0.8-2mm and position d=±2mm, the position signal has a linear relation with position d and the linear range exceeds ±2mm when s=0.8-2mm. With channel cross-talk and channel inconsistency being considered, the stimulation results also are given. Finally, a fast beam transverse profile monitor is designed and provides turn-by-turn measurement of the beam transverse profile.

MOPME042

A PRELIMINARY SIMULATION OF BPM SIGNAL DIODE DETECTOR FOR HLS II TUNE MEASUREMENT SYSTEM*

simulation, betatron, storage-ring, pick-up

565

J.J. Zheng, P. Lu, T.J. Ma, B.G. Sun, Y.L. Yang, J.Y. Zou
USTC/NSRL, Hefei, Anhui, People's Republic of China

Funding: Supported by National Natural Science Foundation of China (11105141, 11175173) and the Fundamental Research Funds for the Central Universities (WK2310000015)
A high sensitivity BPM signal detection front-end electronics has been designed for HLS II tune measurement system according to the HLS II upgrade requirements. Classical tune measurement systems filter out just one or a few of these betatron sidebands frequency. As a consequence, most of the betatron energy is dropped and only a very small energy remains for further processing. A new method, referred to as Direct Diode Detection (3D) by LHC[1], improves the situation. In this paper, the HLS II BPM signals have been calculated out in time domain and frequency domain. Basing on the characteristics of HLS II BPM signal, a preliminary simulation is performed to test and verify the feasibility of diode detector for HLS II tune measurement system. The simulation results clearly show that the technique of diode-based circuit can be applied to HLS II tune measurement.

MOPME053

Point Spread Function Study of X-ray Pinhole Camera in SSRF

radiation, synchrotron-radiation, emittance, storage-ring

592

Z.C. Chen, J. Chen, G.Q. Huang, Y.B. Leng
SSRF, Shanghai, People's Republic of China

Funding: Supported by National Natural Science Foundation of China (11075198)
An X-ray Pinhole Camera that has been used to present the transverse beam size with an intuitive grasp of the distribution of the beam radiation was installed on one beam-line of the storage ring in Shanghai Synchrotron Radiation Facility (SSRF). The real beam size however is a function of the image size of the CCD camera and the point spread function (PSF) of the system. The PSF was calculated but poorly tested. This article will present the measurement of the PSF with a series of beam based experiments and the consistency with the theoretical beam size.

MOPME054

Bunch-by-bunch Beam Position and Charge Monitor based on Broadband Scope in SSRF

injection, storage-ring, pick-up, synchrotron-radiation

595

Y. Yang, Y.B. Leng, Y.B. Yan, N. Zhang
SSRF, Shanghai, People's Republic of China

A bunch-by-bunch beam position and charge monitor system, based on a broadband oscilloscope, has been developed at SSRF. The beam positions of each bunch could be located independently in this system by using the original signals from the button-type pickups on the storage ring. The relative charge of each bunch could be obtained by the sum signal from the pickups. Using sum weighted average method, turn-by-turn beam position could be got from the bunch-by-bunch beam position data. The difference of each bunch beam position have been observed during injection at SSRF.

MOPME064

SLM and Flags for Booster of NSLS-II

booster, vacuum, radiation, synchrotron-radiation

622

O.I. Meshkov, V. Smalyuk
BINP SB RAS, Novosibirsk, Russia
V.L. Dorokhov
BINP, Novosibirsk, Russia

Set of diagnostics of booster of NSLS-II includes 6 fluorescent screens (flags) and 2 synchrotron light monitors (SLM). The flags will be applied during booster commissioning for closing of the beam turn. They are also a useful tool in case of malfunction elimination. SLM will be used both for booster comissioning and for operation. The details of calibration and design of the devices are discussed.

MOPME073

Measurement of Schottky-like Signals from Linac Bunched Hadron Beams for Momentum Spread Evaluation

linac, cavity, pick-up, bunching

649

P. Kowina, P. Forck, R. Singh
GSI, Darmstadt, Germany
F. Caspers
CERN, Geneva, Switzerland
R. Singh
TEMF, TU Darmstadt, Darmstadt, Germany

We present a novel method for the measurement of Linac beam parameters in the longitudinal phase space. The longitudinal momentum spread can be evaluated by means of Schottky type signal analysis of bunched beams. There is a close similarity between a repetitive Linac bunch train and a circulating beam with a single short batch in a large machine like the LHC. A dedicated longitudinal cavity pick-up was used in the Linac where resonance frequency and Q-value were carefully selected in order to get an optimum compromise between the unavoidable coherent signal and the desired incoherent part of the beam spectrum. A time domain gating similar to the 4.8 GHz LHC Schottky front-end is applied. As a cross-check of the validity of the interpretation in terms of momentum spread, the Linac beam is analyzed in the downstream synchrotron using standard Schottky methods. In principle, this approach can be understood as an extension of Schottky analysis for circular machines with a perfect “mixing” between subsequent bunch trains. This contribution describes the test set-up and discusses the results of the measurements with a heavy ion beam.

MOPWA001

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

pick-up, ion, controls, 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.

MOPWA007

Operating Experience of Kicker Magnet System in the J-PARC 3GeV RCS

kicker, high-voltage, extraction, neutron

678

K. Suganuma, M. Kinsho, T. Togashi, M. Watanabe
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan

The J-PARC 3-GeV rapid cycling synchrotron (RCS) has been provided proton beam to the Material and Life Science Facility (MLF)as well as to the 50 GeV Main Ring (MR). Proton beam is accelerated from 181 MeV to 3GeV in the RCS and immediately extracted it to the beam transport line to the MLF and the MR. Extraction kicker system is used for this fast extraction. The RCS has been operated for the neutron and MLF users program from December 23rd, 2008. At the beginning of user operation there were many troubles for the extraction kicker system, especially, thyratron which are used for switch of power supply often caused failure. The beam stop rate due to RCS extraction kicker system was more than 13% in the total beam stop of the J-PARC, establishment and operation experience of the tuning for power supply of the extraction kicker make the beam stop rate less than 0.5% in November 2012. In this paper, we are going to report about daily operation whose main is about operation of thyratron and the maintenance held in summer 2012. And　 We also going to report about the aptitude test of thyratron as a plan of the future.

MOPWA019

Digital Power Supply Controller Development Based on FPGA

power-supply, controls, booster, 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.

MOPWA041

The New SLS Beam Size Monitor, First Results

laser, emittance, polarization, radiation

759

Á. Saá Hernández, N. Milas, M. Rohrer, V. Schlott, A. Streun
PSI, Villigen PSI, Switzerland
Å. Andersson, J. Breunlin
MAX-lab, Lund, Sweden

Funding: This research has received funding from the European Commission under the FP7-INFRASTRUCTURES-2010-1/INFRA-2010-2.2.11 project TIARA (CNI-PP). Grant agreement no. 261905.
An extremely small vertical beam size of 3.6 μm, corresponding to a vertical emittance of 0.9 pm, only about five times bigger than the quantum limit, has been achieved at the storage ring of the Swiss Light Source (SLS). The measurement was performed by means of a beam size monitor based on the imaging of the vertically polarized synchrotron radiation in the visible and UV spectral ranges. However, the resolution limit of the monitor was reached during the last measurement campaign and prevented further emittance minimization. In the context of the work package “SLS Vertical Emittance Tuning” of the TIARA collaboration, a new improved monitor was built. It provides larger magnification, an increase of resolution and enables two complementary methods of measurement: imaging and interferometry. In this paper we present the design, installation, commissioning, performance studies and first results obtained with the new monitor.

MOPWA044

TLS Booster Measurement and Observation by New BPM Electronics

booster, quadrupole, extraction, kicker

768

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

Taiwan Light Source (TLS) is a 1.5 GeV synchrotron based light source and its booster synchrotron was delivered in 1992. Due to the new project Taiwan Photon Source proceeded at the same site, some up-to-date device are available now before TPS civil construction complete and temporarily adapted for TLS booster to improve its operations. The major parameters of the TLS booster synchrotron are measured. It also provides a chance to experience for the TPS project booster diagnostic.

MOPWA060

DITANET - An International Network in Beam Diagnostics

diagnostics, electron, photon, instrumentation

813

C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom
C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom

Funding: Work supported by the EU under contract 215080.
Beam diagnostics systems are essential constituents of any particle accelerator; they reveal the properties of a beam and how it behaves in a machine. Without an appropriate set of diagnostic elements, it would simply be impossible to operate any accelerator complex, let alone optimize its performance. Beam diagnostics is also a rich field in which a great variety of physical effects are made use of and consequently provides a wide interdisciplinary base for the training of researchers. The DITANET Consortium develops beyond state-of-the-art beam diagnostic techniques for hadron and electron accelerators and trained more than 20 researchers between 2008 and 2012. This contribution summarizes the network's research outcomes in beam instrumentation and diagnostics.

MOPWA066

Components of Heating and Fueling of Fusion Plasmas

high-voltage, simulation, controls, cathode

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.

MOPWA073

A Turn-by-turn Beam Profile Monitor using Visible Synchrotron Radiation at CESR-TA

electron, synchrotron-radiation, radiation, emittance

849

S. Wang, D. L. Rubin, C.R. Strohman
CLASSE, Ithaca, New York, USA
R.F. Campbell, R. Holtzapple
CalPoly, San Luis Obispo, California, USA

Funding: Work supported by the National Science Foundation and Department of Energy under contract numbers PHY-0734867, PHY-1002467, DMR-0936384, and DE-FC02-08ER41538, DE-SC0006505
A fast beam profile monitor using visible synchrotron radiation (SR) has been constructed and installed in Cornell Electron Storage Ring. This monitor utilizes fast readout electronics based on the Hamamatsu H7260K multi-anode photomultiplier, which has a 32-channel linear array with 1mm channel pitch and sub-nanosecond rise time. In a low emittance lattice at 2 GeV, a double-slit interferometer is employed to measure the horizontal beam size. After careful calibration of the interference pattern, the horizontal beam size within a range of 100 to 500 microns can be measured with a precision of ±5 microns. Due to finite array size, the small vertical beam size is measured by imaging the pi-polarized component of the SR. The fast beam profile monitor is capable of measuring bunch-by-bunch turn-by-turn transverse beam sizes, which eliminates beam jitter inherent when imaging the average beam size with a CCD camera. Details of hardware and software controls are also discussed.

MOPWO005

Simulating Spin Dynamics and Depolarization using POLE

resonance, simulation, polarization, synchrotron-radiation

891

J.F. Schmidt, O. Boldt, F. Frommberger, W. Hillert
ELSA, Bonn, Germany

Funding: BMBF
The spin dynamics in circular accelerators with fast energy ramps, or short storage times of up to some seconds, can be investigated with spin tracking appropriately. Additionally, the spin motion of lepton beams is affected significantly by synchrotron radiation. Hence, spin dynamics simulations require spin tracking with a large number of particles to compute the beam polarization and thus take considerably long computing times. Therefore, high efficiency is crucial to perform systematic polarization studies. The new simulation tool POLE provides the ability to balance accuracy against computing time. To that end, adjustable approximations of magnetic fields and synchrotron radiation are implemented. POLE is accessible for a wide range of lepton storage rings because it uses the common MAD-X lattice files and the corresponding particle tracking results.

MOPWO006

Eigenmode Computation for the GSI SIS18 Ferrite Cavity

cavity, resonance, heavy-ion, ion

894

K. Klopfer, W. Ackermann, T. Weiland
TEMF, TU Darmstadt, Darmstadt, Germany

Funding: Supported by GSI
At the GSI Helmholtzzentrum für Schwerionenforschung in Darmstadt the heavy-ion synchrotron SIS18 is operated to further accelerate stable nuclei of elements with different atomic numbers. Two ferrite-loaded cavity resonators are installed within this ring. During the acceleration phase their resonance frequency has to be adjusted to the revolution frequency of the heavy-ions to reflect their increasing speed. To this end, dedicated biased ferrite-ring cores are installed inside the cavities for a broad frequency tuning. By properly choosing a suited bias current, the differential permeability of the ferrite material is modified, which finally enables to adjust the eigenfrequency of the resonator system. Consequently, the actual resonance frequency strongly depends on the magnetic properties of the ferrites. The goal of the current study is to numerically determine the lowest eigensolutions of the GSI SIS18 ferrite-loaded cavity. For this purpose, a new solver based on the Finite Integration Technique has been developed.

MOPWO037

SixTrack Simulation of Off-momentum Cleaning in LHC

simulation, radiation, betatron, synchrotron-radiation

972

E. Quaranta, R. Bruce, S. Redaelli
CERN, Geneva, Switzerland

In the LHC, high-amplitude particles are cleaned by either betatron collimators or momentum collimators. Previously, betatron losses have been considered more important, but measurements during the first years of operation show high losses also in the off-momentum cleaning insertion. This causes a significant radiation dose to warm magnets downstream of the collimators. Our work in this paper aims at simulating with SixTrack the off-momentum particles, driven into the momentum collimators by radiation damping outside the RF system acceptance. The results are an important ingredient in assessing the effectiveness of new passive absorbers to protect the warm magnets.

MOPWO087

Parameter Estimation of the Exponentially Damped Sinusoid for Noisy Signals

closed-orbit, neutron, damping, feedback

1079

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
The damped sinusoid equation is a common model for many scientific processes involving damped periodic signals. Here we present two methods for estimating the damped sinusoid parameters for noisy signals. Both methods are based upon an exact, closed form solution to fit the parameters for signals without noise, and they estimate the parameters for the noisy signals by the statistical maximum likelihood criterion. The first method relies on an optimizer to minimize the mean square signal error. The second method estimates the parameters by direct calculation and is suitable when the signal noise is small and the frequencies are sufficiently far from the integer and half integer values.

TUOAB202

ILSF, A Third Generation Light Source Laboratory in Iran

storage-ring, dipole, quadrupole, cavity

1137

J. Rahighi, M.R. Khabazi
IPM, Tehran, Iran
E. Ahmadi, H. Ajam, M. Akbari, S. Amiri, A. Babaei, J. Dehghani, R. Eghbali, J. Etemad Moghadam, S. Fatehi, M. Fereidani, H. Ghasem, A. Gholampour, A. Iraji, M. Jafarzadeh, B. Kamkari, S. Kashani, P. Khodadoost, H. Khosroabadi, M. Moradi, H. Oveisi, S. Pirani, M. Rahimi, M. Razazian, A. Sadeghipanah, F. Saeidi, R. Safian, E. Salimi, Kh.S. Sarhadi, O. Seify, M.Sh. Shafiee, A. Shahveh, A. Shahverdi, D. Shirangi, E.H. Yousefi
ILSF, Tehran, Iran
D. Einfeld
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

The Iranian Light Source Facility (ILSF) project is a first large scale accelerator facility which is currently under planning in Iran. The circumference of the storage ring is 297.6 m with the energy of 3 GeV. The facility will be built on a land of 100 hectares area in the city of Qazvin, located 150 km West of Tehran. The city is surrounded by many universities, research centers and industrial companies. The design and construction of prototype items such as radio frequency solid state amplifier, dipole magnets, highly stable magnet power supplies and girders have already begun. A low field H-type dipole magnet with the central field of 0.5T at the gap of 34mm and length of 500mm was built and tested in site. Also a prototype storage ring quadrupole with a 18 T/m gradient and 233 iron length is in now in fabrication process. Site selection studies, including geotechnical and seismological measurements are being performed. Conceptual Design Report, CDR, as the first milestone of the project has been published on October 2012.

Slides TUOAB202 [5.173 MB]

TUODB201

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

cavity, impedance, acceleration, controls

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]

TUPEA005

Effects of Quantum Diffusion on Electron Trajectories and Spontaneous Synchrotron Radiation Emission

electron, radiation, photon, undulator

1170

I.V. Agapov, G. Geloni
XFEL. EU, Hamburg, Germany
O.V. Chubar
BNL, Upton, Long Island, New York, USA

For various cases, e.g. in the long undulator sections of the European XFEL, quantum diffusion and energy loss have a noticable effect on the electron trajectory, which in turn affects the properties of the emitted radiation. We discuss approaches to modelling the electron dynamics taking this into account and the effect it has on spontaneous radiation emission.

TUPFI063

Electromagnetic Coupling between High Intensity LHC Beams and the Synchrotron Radiation Monitor Light Extraction System

simulation, resonance, impedance, extraction

1493

F. Roncarolo, W. Andreazza, A. Bertarelli, E. Bravin, F. Caspers, M. Garlaschè, A. Goldblatt, J-J. Gras, O.R. Jones, T. Lefèvre, E. Métral, A.A. Nosych, B. Salvant, G. Trad, R. Veness, C. Vollinger, M. Wendt
CERN, Geneva, Switzerland

The CERN LHC is equipped with two Synchrotron Radiation Monitor systems used to characterise transverse and longitudinal beam distributions. Since the end of the 2011 LHC run the light extraction system, based on a retractable mirror, has suffered deformation and mechanical failure that is correlated to the increase in beam intensity. Temperature probes have associated these observations to a strong heating of the mirror support with a dependence on the longitudinal bunch length and shape, indicating the origin as electromagnetic coupling between the beam and the structure. This paper combines all this information with the aim of characterising and improving the system in view of its upgrade during the current LHC shutdown. Beam-based observations are presented along with electromagnetic and thermomechanical simulations and complemented by laboratory measurements, including the study of the RF properties of different mirror bulk and coating materials.

TUPME011

Simulated Beam-beam Limit for Circular Higgs Factories

luminosity, simulation, beam-beam-effects, radiation

1586

K. Ohmi
KEK, Ibaraki, Japan
F. Zimmermann
CERN, Geneva, Switzerland

We report simulation studies of the beam-beam limit for two proposed circular e⁺e⁻ Higgs factories with circumference of 27 and 80 km, respectively, called LEP3 and TLEP. In particular we investigate the dependence of the steady-state luminosity and transverse beam sizes on the synchrotron tune (or momentum compaction factor) and on the betatron tunes, as well as the consequences of the strong radiation damping and the implications of the large hourglass effect.

TUPME017

Validation of the Microwave Instability in the Damping Ring of SuperKEKB using VFP Solver

impedance, damping, simulation, wakefield

1604

L. Wang
SLAC, Menlo Park, California, USA
H. Ikeda, K. Ohmi, K. Oide, D. Zhou
KEK, Ibaraki, Japan

Microwave instability driven by CSR impedance in the damping ring of Super-KEKB is a concern due to its high bunch current. To understand the beam dynamics, we simulate the microwave instability using Vlasov-Fokker-Planck (VFP) solver. The longitudinal wake potential is calculated as a sum of the contributions due to vacuum chamber components distributed around the ring, including geometry wake field and CSR wake. To improve the accuracy of the simulation of microwave instability, the coherent synchrotron radiation impedance is calculated to very high frequency to get more accurate wake field with a short bunch. The CSR wake is much larger than the geometry wake. The threshold is just above the design current and saw-tooth type of instability is found above the threshold.

TUPME018

Construction of New 90 MeV Injector Linac for the 1.2 GeV Booster Synchrotron at Tohoku University

linac, gun, electron, quadrupole

1607

S. Kashiwagi, H. Hama, F. Hinode, M. Kawai, T. Muto, I. Nagasawa, K. Nanbu, Y. Shibasaki, K. Takahashi
Tohoku University, Research Center for Electron Photon Science, Sendai, Japan
N.Y. Huang
NTHU, Hsinchu, Taiwan

The Great East Japan Earthquake (March 11, 2011) has inflicted enormous damage on the accelerator facility of Research Center for Electron Photon Science, Tohoku University. A 300 MeV linac operated for 46 years as an accelerator for radioisotope production and also as an injector of the 1.2 GeV booster synchrotron for nuclear physics experiments. The accelerator will be rebuilt with all the recyclable components. New small linac is constructed as the injector for the booster synchrotron. The injector consists of thermionic rf-gun, two 3m-long accelerating structures, and transport line to the synchrotron. The maximum energy of injector is 90 MeV with beam loading. The detail of the injector linac is introduced in this conference.

TUPME021

Optimization Parameter Design of a Circular e⁺e⁻ Higgs Factory

luminosity, factory, emittance, collider

1616

D. Wang, Y.W. An, J. Gao, H. Geng, Y.Y. Guo, Q. Qin, N. Wang, S. Wang, M. Xiao, G. Xu, S.Y. Xu
IHEP, Beijing, People's Republic of China

Funding: NSFC:11175192
In this paper we will show a genral method of how to make an optimized parameter design of a circular e⁺e⁻ Higgs Factory by using analytical expression of maximum beam-beam parameter and beamstrahlung beam lifetime started from given design goal and technical limitations. A parameter space has been explored.

TUPME045

Turn-by-turn Measurements in the KEK-ATF

damping, injection, betatron, emittance

1664

Y. Renier, Y. Papaphilippou, R. Tomás, M. Wendt
CERN, Geneva, Switzerland
N. Eddy
Fermilab, Batavia, USA
K. Kubo, S. Kuroda, T. Naito, T. Okugi, N. Terunuma, J. Urakawa
KEK, Ibaraki, Japan

The ATF damping ring has been upgraded with new read-out electronics for the beam position monitors (BPM), capable to acquire the beam orbits on a turn-by-turn basis, as well as in a high resolution averaging mode. The new BPM system allows to improve optic corrections and to achieve an even smaller vertical emittance (<2pm). Experimental results are presented based on turn-by-turn beam orbit measurements in the ring, for estimating the beta functions and dispersion along the lattice. A fast method to measure spectral line amplitude in a few turns is also presented, including the evaluation of chromaticity.

TUPME056

3.5 GeV Superconducting Stacking Ring for Compton Based Polarized Positrons Source of CLIC

positron, injection, damping, emittance

1697

E.V. Bulyak, P. Gladkikh, A.A. Kalamayko
NSC/KIPT, Kharkov, Ukraine
T. Omori, J. Urakawa, K. Yokoya
KEK, Ibaraki, Japan
L. Rinolfi, F. Zimmermann
CERN, Geneva, Switzerland

This paper describes 3.5 GeV superconducting storage ring dedicated to positron accumulation as part of a polarized positron source for CLIC, based on Compton scattering in a Compton storage ring. The superconducting stacking ring can provide a synchrotron damping time of order 250 microseconds. Together with combined injection scheme in the longitudinal and transverse plane, such a ring may solve the problem of accumulating a positron beam with efficiency close to 95 % and with the beam intensity required for CLIC.

TUPWA015

The Study of Bunch Lengthening in Electron Storage Ring

impedance, storage-ring, luminosity, electron

1757

Y. Li, L. Wang, Y. Zhang
IHEP, Beijing, People's Republic of China

The bunch length of electron storage ring of BEPCII was measured repeatedly during steady synchronous mode and streak camera was calibrated well. From the bench lengthening , the coupling impedance of the whole ring was estimated, which was according with theoretic impedance budget . Meanwhile, the small ap optics for improving the luminosity was feasible in collision mode form synchronous result .

TUPWA024

The Beam Gass Coulomb Scattering in Electron Storage Ring

scattering, simulation, electron, radiation

1778

X.L. Yu, Z. Bai, W.W. Gao, W. Li, L. Wang
USTC/NSRL, Hefei, Anhui, People's Republic of China

Among the various factors which determine the beam life time of the HLSII electron storage ring, the beam loss due to the scattering on residual gas is simulated using MC method. The paper will give the process of elastic and inelastic scattering, and the probability of each scattering is calculated, then using MC sampling to decide which particles will participate in the collision. Tracking the beam with scattering of beam-gas included, the spatial distribution of beam will be obtained. Finally we will give the influence analysis of beam-gas scattering.

TUPWA040

Loss of Landau Damping for Inductive Impedance in a Double RF System

damping, emittance, simulation, impedance

1796

T. Argyropoulos, E.N. Shaposhnikova
CERN, Geneva, Switzerland
A.V. Burov
Fermilab, Batavia, USA

In this paper the thresholds of the loss of Landau damping due to the presence of inductive impedance in a single and double harmonic RF systems are determined, both from calculations and particle simulations. High harmonic RF system, operating in bunch lengthening mode is used in many accelerators with space charge or inductive impedance to reduce the peak line density or stabilize the beam. An analytical approach, based on emerging of the discrete Van Kampen modes, shows that improved stability in a double RF system can be achieved only below some critical value of longitudinal emittance. Above this threshold, a phase shift of more than 15 degrees between the two RF components is proven to stabilize the bunch. These results, confirmed also by particle simulations, are able to explain now observations during the ppbar operation of the SPS. The thresholds in bunch shortening mode as well as in a single RF case are compared with this regime.

TUPWA063

Dependence of Vertical Beam Dynamics Influenced by Electron Clouds at CesrTA on Variations in Bunch Spacing and Vertical Chromaticity

electron, positron, emittance, feedback

1847

R. Holtzapple, R.F. Campbell, E.L. Holtzapple
CalPoly, San Luis Obispo, California, USA
M.G. Billing, K.R. Butler, G. Dugan, M.J. Forster, B.K. Heltsley, G. Ramirez, N.T. Rider, J.P. Shanks, K.G. Sonnad
CLASSE, Ithaca, New York, USA
J.W. Flanagan
KEK, Ibaraki, Japan

Funding: Work supported by DOE Award DE-FC02-08ER41538, NSF Award PHY-0734867, PHY-1068662 and the Lepton Collider R&D Coop. Agreement: NSF Award PHY-1002467
Experiments have been performed on the Cornell Electron-Positron Storage Ring Test Accelerator (CesrTA) to probe the interaction of the electron cloud with a 2-Gev stored positron beam. The purpose of these experiments was to characterize the beam–electron cloud interactions by varying the vertical chromaticity and bunch spacing. These experiments were performed on a 30-bunch positron train, at a fixed current of 0.75mA/bunch, where the bunch spacing was varied between 4 and 28ns at three different vertical chromaticity settings. The vertical beam dynamics of the stored beam, in the presence of the electron cloud, was quantified using the x-ray beam size monitor (xBSM) that is used to measure the bunch-by-bunch, turn-by-turn vertical beam size of the bunch trains. In this paper, we report the results from these experiments and discuss the effects of the electron cloud on the CesrTA beam dynamics.

TUPWO015

Off-Energy Injection Into Newsubaru

injection, lattice, septum, betatron

1913

Y. Shoji
LASTI, Hyogo, Japan
Y. Minagawa, Y. Takemura
JASRI/SPring-8, Hyogo-ken, Japan

NewSUBARU is temporarily operated in non-achromatic mode for the research using chromaticity modulation. At this special mode, a normal injection scheme does not work because of the larger stored beam size and smaller ring acceptance. In order to obtain good injection efficiency, which enables top-up operation, the injected beam energy is displaced from the ring energy. The finite dispersion of 1.1 m at the injection point and the energy displacement of 0.7% reduce the betatron oscillation amplitude of the injected beam. A trade off is a synchrotron oscillation produced by the energy mismatch. Using this technique, it became possible to inject new beam using a closed fast injection bump and also a top-up operation. Although it is not possible to inject beam to a normal achromatic lattice using a closed bump. Especially in non-achromatic quasi-isochronous ring, it would be possible that the energy mismatch is reduced by the betatron amplitude dependent shift of the equilibrium energy.

TUPWO023

Parasitic Slow Exraction of Extremely Weak Beam From a High-intensity Proton Rapid Cycling Synchroton

scattering, extraction, proton, simulation

1931

Y. Zou, H.T. Jing, C. Meng, J.Y. Tang, Z. Yang
IHEP, Beijing, People's Republic of China

This paper proposes a new method to extract extremely weak beam from a high-intensity proton rapid cycling synchrotron in the parasitic mode, while maintaining the normal fast extraction. The usual slow extraction from a synchrotron by third-order resonance method cannot be applied in a RCS due to very short flat-top at the extraction energy. This is even more difficult when it is high-intensity synchrotron due to the strict control on beam loss. The parasitic slow extraction method to extract extremely weak beam from the RCS of CSNS has been studied in details. By moving only beam halo to a scatting foil in the arc region by a local orbit bump in about 2 ms before the fast extraction, one can extract a very small part of the scattered particles with very limited beam loss in the process. At 1.6 GeV and 62.5 A in beam power, halo particles of about 10^-4 total particles are involved in the parasitic slow extraction can result in a beam intensity of 2105 protons per cycle or lower. Detailed studies including scattering effect in the foil, orbit bumps by bump magnets and energy displacement by adjusting RF, and multi-particle simulations by ORBIT and TURTLE codes are presented.

TUPWO054

Recent Results from the EMMA Experiment

acceleration, simulation, betatron, closed-orbit

1988

B.D. Muratori, J.K. Jones
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
R. Appleby, J.M. Garland, H.L. Owen
UMAN, Manchester, United Kingdom
J.S. Berg, F. Méot
BNL, Upton, Long Island, New York, USA
C.S. Edmonds, J.K. Jones, I.W. Kirkman, B.D. Muratori, A. Wolski
Cockcroft Institute, Warrington, Cheshire, United Kingdom
C.S. Edmonds, I.W. Kirkman, A. Wolski
The University of Liverpool, Liverpool, United Kingdom
D.J. Kelliher, S. Machida
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
J. Pasternak
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
J. Pasternak
Imperial College of Science and Technology, Department of Physics, London, United Kingdom

EMMA (Electron Model for Many Applications) is a prototype non-scaling electron FFAG hosted at Daresbury Laboratory. After a recent demonstration of acceleration in the serpentine channel, the injected EMMA beam was further studied. This entails the continuation of the exploration of the large transverse and longitudinal acceptance and the effects of slower integer tune crossing on the betatron amplitude. A single closed orbit correction that is effective at multiple momenta (and hence over a significant range in tune space) was implemented. A comparison with a detailed model based on measured field maps, and the experimental mapping of the machine by relating the initial and final phase space coordinates was also done. These recent results together with more practical improvements such as injection orbit matching with real-time monitoring of the coordinates in the transverse phase space will be reported in this paper.

TUPWO055

Phase Rotation Experiment at EMMA for testing Applicability of a Non-scaling FFAG for PRISM System

extraction, acceleration, background, electron

1991

B.D. Muratori, J.K. Jones
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
R.T.P. D'Arcy
UCL, London, United Kingdom
J.K. Jones, B.D. Muratori
Cockcroft Institute, Warrington, Cheshire, United Kingdom
D.J. Kelliher, S. Machida
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
H.L. Owen
UMAN, Manchester, United Kingdom
J. Pasternak
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
J. Pasternak
Imperial College of Science and Technology, Department of Physics, London, United Kingdom

EMMA is the world’s first non-scaling FFAG, based at Daresbury Laboratory. EMMA has a very large acceptance and has demonstrated acceleration in the serpentine channel. PRISM (Phase Rotated Intense Slow Muon source) is a next generation muon to electron conversion experiment aiming to obtain intense quasi-monochromatic low energy muon beams by performing RF phase rotation in an FFAG ring. Current baseline design for PRISM applies the scaling FFAG ring, but an alternative machine could be based on a ns-FFAG principle. As the transverse-longitudinal coupling is present in ns-FFAGs due to a natural chromaticity, its effect on the final energy spread and beam quality needs to be tested. In order to gauge the expected results, an experiment was designed to be performed on EMMA. We report here the details of this experiment and the results gathered from EMMA operation.

TUPWO061

Design of a Soft Orbit Bump for FEL Mirror Protection at Duke FEL/HIGS Facility

FEL, radiation, electron, synchrotron-radiation

2006

H. Hao, J.Y. Li, S.F. Mikhailov, Y.K. Wu
FEL/Duke University, Durham, North Carolina, USA

Funding: This work is supported in part by the US DOE grant no. DE-FG02-97ER41033.
In an oscillator Free-Electron Laser (FEL) with a high energy electron beam, it is critical to minimize harmful high-energy radiation on the downstream FEL mirror in order to increase its lifetime. At the High Intensity Gamma-ray Source (HIGS) facility at Duke University, effort has been devoted to developing a variety of techniques to reduce the amount of radiation on the FEL mirror. One of the most effective methods was the use of a set of adjustable in-vacuum apertures to block harmonic radiation from FEL wigglers. In recent studies, it was determined that the edge radiation from the end-of-the-arc bending magnet is the main source of UV/VUV and x-ray radiation which causes mirror damage. To mitigate this effect, a soft orbit bump is designed to change the displacement and angle of the electron beam around the end-of-the-arc area. This soft orbit bump is developed using the multi-objective optimization technique. Calculation shows the soft orbit bump can significantly reduce the flux of high energy photons on the FEL mirror. Study is also performed to determine the impact of this orbit bump on the injection, beam lifetime, and the FEL and gamma-ray operation at HIGS facility.

WEXB101

Optics Optimization for Reducing Collective Effects and Raising Instability Thresholds in Lepton and Hadron Rings

optics, emittance, collective-effects, brightness

2033

Y. Papaphilippou, F. Antoniou, H. Bartosik
CERN, Geneva, Switzerland

This paper covers recent progress in the design of optics solutions to minimize collective effects such as beam instabilities, intra-beam scattering or space charge in hadron and lepton rings. The necessary steps are reviewed for designing the optics of high-intensity and high-brightness synchrotrons but also ultra-low emittance lepton storage rings, whose performance is strongly dominated by collective effects. Particular emphasis is given to proposed and existing designs illustrated by simulations and beam measurements.

Slides WEXB101 [24.511 MB]

WEOAB101

Single Particle Tracking for Simultaneous Long and Short Electron Bunches in the BESSY II Storage Ring

cavity, HOM, simulation, optics

2038

M. Ruprecht, A. Jankowiak, A. Neumann, M. Ries, G. Wüstefeld
HZB, Berlin, Germany
T. Weis
DELTA, Dortmund, Germany

A scheme where 1.5 ps and 15 ps long bunches (rms) can be stored simultaneously in the BESSY II storage ring has recently been proposed (BESSY^VSR*). This paper presents simulations of single particle beam dynamics influenced by superconducting cavities used for the strong longitudinal beam focusing. The effect of RF jitter on (very short) bunches is investigated and results are discussed. Furthermore, possible effects on beam dynamics during ramp up and ramp down of the high gradient fields in the cavities are studied. The primary goal is to reveal preliminary design specifications for RF jitter on the basis of single particle dynamics.
* G. Wüstefeld, A. Jankowiak, J. Knobloch, M. Ries, Simultaneous Long and Short Electron Bunches in the BESSY II Storage Ring, Proceedings of IPAC2011, San Sebastián, Spain

Slides WEOAB101 [3.955 MB]

WEOAB102

CSR-driven Longitudinal Single Bunch Instability Thresholds

impedance, resonance, damping, electron

2041

P. Kuske
BESSY GmbH, Berlin, Germany

According to Bane, et al.* threshold currents should follow a quite simple scaling law. More detailed theoretical results for the underlying shielded CSR-interaction have been performed for BESSY-II and the MLS and will be presented in comparison with observations at these storage rings. It is found that there are parameter regions where the instability is weak and thus thresholds depend on damping time and synchrotron tune. Theoretical findings are in surprisingly good agreement with most of the observed instability features.
* K.L. Bane, et al., Phys. Rev. ST-AB 13, 104402 (2010)

Slides WEOAB102 [0.779 MB]

WEOBB202

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

radiation, electron, controls, 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]

WEPWA005

Experimental Characterization of the Coherent Harmonic Generation Source at the DELTA Storage Ring

laser, radiation, electron, undulator

2132

M. Huck, H. Huck, M. Höner, S. Khan, R. Molo, A. Schick, P. Ungelenk
DELTA, Dortmund, Germany
S. Cramm, L. Plucinski, C.M. Schneider
Forschungszentrum Jülich, Peter-Gruenberg-Institut-6, Jülich, Germany
S. Döring, L. Plucinski, C.M. Schneider
Universität Duisburg-Essen, Duisburg, Germany

Funding: Work supported by DFG, BMBF, and by the Federal State NRW.
The short-pulse facility at the 1.5-GeV synchrotron light source DELTA, operated by the TU Dortmund University, generates coherent VUV and THz radiation by Coherent Harmonic Generation (CHG). Here, a femtosecond laser pulse interacts with an electron bunch in an undulator causing a periodic energy modulation and subsequent micro-bunching, which gives rise to coherent radiation at harmonics of the seed wavelength. Rather than using Ti:Sapphire laser pulses at 795 nm directly, the second harmonic is employed for seeding since 2012. After significant modifications of the seed laser beamline and the dispersive chicane to improve the microbunching, the last commissioning steps include characterization of the CHG radiation and preparing the experimental setup at an existing VUV beamline for time-resolved photoemission spectroscopy. In this paper, the status of the project and recent experimental results are presented.

WEPWA006

Beam Heat Load Measurements with COLDDIAG at the Diamond Light Source

electron, synchrotron-radiation, radiation, impedance

2135

S. Gerstl, S. Casalbuoni, A.W. Grau, T. Holubek, D. Saez de Jauregui, R. Voutta
KIT, Eggenstein-Leopoldshafen, Germany
R. Bartolini, M.P. Cox, E.C. Longhi, G. Rehm, J.C. Schouten, R.P. Walker
Diamond, Oxfordshire, United Kingdom
M. Migliorati, B. Spataro
INFN/LNF, Frascati (Roma), Italy

Understanding the heat load from an electron beam is still an open issue for the cryogenic design of superconducting insertion devices. COLDDIAG, a cold vacuum chamber for diagnostics was designed and built specially for this purpose. With the equipped instrumentation, which covers temperature sensors, pressure gauges, mass spectrometers as well as retarding field analyzers it is possible to measure the beam heat load, total pressure, and gas content as well as the net flux and energy of particles hitting the chamber walls. Following a failure after its first installation in November 2011, COLDDIAG was subsequently reinstalled in the Diamond storage ring in August 2012. We report on the preliminary results that have been obtained since then.

WEPWA007

First Tests with a Local and Integral Magnetic Field Measurement Setup for Conduction Cooled Superconducting Undulator Coils

undulator, vacuum, radiation, synchrotron-radiation

2138

A.W. Grau, S. Casalbuoni, S. Gerstl, N. Glamann, T. Holubek, D. Saez de Jauregui
KIT, Eggenstein-Leopoldshafen, Germany

The magnetic field quality of insertion devices (IDs) has a significant influence on their performance. Therefore it is essential to characterize their magnetic properties and perform precise field measurements before installation in synchrotron light sources. Particularly for permanent magnet IDs the magnetic field measurement technology made significant progress during the last years and pushed the capabilities of synchrotron light sources. Even though for superconducting IDs the measurement settings are far more challenging similar major developments are required. As a part of our R&D program on superconducting IDs we perform quality assessment of their magnetic field properties. This contribution describes details, challenges and the first tests with the measurement equipment configurations to perform measurements of the integral and local magnetic field distributions of superconducting undulator coils up to 2 m length, in a cold (4.2 K), in-vacuum and cryogen free environment.

WEPWA012

Preliminary Design of Transfer Lines for the ILSF Accelerator Complex

booster, storage-ring, linac, electron

2153

H. Ghasem
IPM, Tehran, Iran
E. Ahmadi, F. Saeidi
ILSF, Tehran, Iran

There are two transfer lines (T-lines) which link the Iranian Light Source Facility (ILSF) accelerator complex to gather. Several criterias have been considered in design stage of the T-lines. This paper gives linear optimization results of the designed T-lines based on the first layout of the ILSF.

WEPWA030

Using the Power Spectral Density Method to Characterize and Evaluate the X-ray Mirrors Surfaces

simulation, focusing, optics, brilliance

2196

W.Q. Hua, F.G. Bian, Y.M. He, W.H. Lin, L. Song, J. Wang, N. Zhao
SINAP, Shanghai, People's Republic of China

Rapid progress in synchrotron X-ray beams’ coherence and X-ray optics performance places a high demand on characterization and evaluation of optical surface figure and slope errors and roughness on meter-long optics over spatial frequencies as short as 0.1mm. In this paper, the propagation model of hard X-ray beams through reflecting mirror surface is proposed based on wave-front propagation, and numerical simulations are performed for predicting the hard X-ray focusing performance of different imperfect mirrors using a Fresnel diffraction calculation. The imperfect mirror surface height maps synthesized from power spectral functions are used to analyze and evaluate the influences of different mirror surface errors on the reflected hard X-ray beam properties.

WEPWA035

Design of a Superconducting Undulator Magnet Prototype for SSRF

undulator, superconductivity, electron, storage-ring

2205

Z.C. Zhang, J. Cui, J.Y. Jiang, M. Li, W. Li, J.P. Xu, J.J. Xu, J.F. Yu
SINAP, Shanghai, People's Republic of China

Funding: Project 11275254 supported by National Natural Science Foundation of China.
A 0.65 T NbTi superconducting undulator magnet prototype with a period length of 16 mm and a period number of 5 for SSRF is designed. The magnetic field simulation shows that it is possible to obtain a peak field of 0.6 T on the beam axis at a magnetic gap of 9 mm, with a current density of 800A/mm2 in the superconducting coils. Two coil formers are machined from SAE10¹⁸ stainless steel and coated with TiO2 for insulation. The dimension of the grooves of the coil windings in the coil formers is 5 mm x 10 mm. Formvar insulated NbTi superconducting wires with a diameter of 0.6 mm are used for the 128 turn coils per core groove. A five periods core of NbTi superconducting magnet is machined from SAE1018 stainless steel and winded with copper wires.

WEPWA052

A Gun to Linac Operation Analysis of the Taiwan Light Source Injector

electron, linac, factory, gun

2235

H.C. Chen, H.H. Chen, S. Fann, S.J. Huang, J.A. Li, C.C. Liang, Y.K. Lin, Y.-C. Liu
NSRRC, Hsinchu, Taiwan

A response surface methodology (RSM) was used to study the gun to linac optimization process of the Taiwan Light Source (TLS) injector at the National Synchrotron Radiation Research Center (NSRRC). A study model, based on artificial neural network (ANN) theory, which uses electron beam tuning knobs as variables, was constructed. An optimization procedure was developed by designating electron beam efficiency as the objective function and the selected beam tuning knobs as the variables. The theoretical model and optimization procedure were both implemented to evaluate the model. By properly applying the constructed optimization procedure, the beam efficiency was improved. This report outlines the details of the gun to linac optimization process experiment.

WEPWO036

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

cavity, superconducting-cavity, cryogenics, controls

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.

WEPEA001

Simulation Studies of Longitudinal RF-noise and Phase Displacement Acceleration as Driving Mechanism for the MedAustron Synchrotron Slow Extraction

extraction, acceleration, simulation, resonance

2501

U. Dorda
EBG MedAustron, Wr. Neustadt, Austria
M. Benedikt, H.O. Schönauer, A. Wastl
CERN, Geneva, Switzerland

MedAustron is a synchrotron based hadron therapy and research facility located in Austria currently entering the installation stage. It is an implementation of the CERN-PIMMS design which proposed induction acceleration by a betatron core as the driving mechanism for the third-order slow resonant extraction. Primarily in order to increase the accelerators flexibility towards future irradiation schemes but also as back-up options, two alternative extraction driving mechanism have been studied: Longitudinal RF-noise and phase displacement acceleration. The advantages as well as the corresponding limitations are explained, analytical estimates and particle tracking results performed with the 2D tracking codes LONG1D and a specifically developed Python based simulation code are presented.

WEPEA010

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

simulation, hadron, controls, 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.

WEPEA011

Bursting Patterns of Coherent Synchrotron Radiation in the ANKA Storage Ring

impedance, radiation, simulation, electron

2516

M. Schwarz, V. Judin, A.-S. Müller
KIT, Karlsruhe, Germany
M. Klein
SOLEIL, Gif-sur-Yvette, France

We report measurements of bursting patterns of coherent synchrotron radiation (CSR) for a wide range of single bunch currents at the ANKA storage ring. The radiation was detected with a fast THz detector, a Hot Electron Bolometer, and its signal acquired with both a spectrum analyzer and an external sampling oscilloscope. Both analysis methods consistently show the onset of bursting at a threshold current with the appearance of strong high frequency bands with higher harmonics in the several 10th of kHz range. For currents higher than twice the threshold value an abrupt change in the bursting pattern occurs. These results are compared with different numerical models solving the one-dimensional Vlasov-Fokker-Planck equation.

WEPEA012

Study of Laser Wakefield Accelerators as Injectors for Synchrotron Light Sources

laser, lattice, simulation, storage-ring

2519

S. Hillenbrand, V. Judin, A.-S. Müller
KIT, Karlsruhe, Germany
R.W. Aßmann, S. Hillenbrand
CERN, Geneva, Switzerland
O. Jansen, A.M. Pukhov
HHUD, Dusseldorf, Germany

Short bunch lengths, high beam energies, and small facility footprint make Laser Wakefield Accelerators (LWFA) very interesting as injectors for Synchrotron Light Sources. In this paper, we describe exemplary investigations for the ANKA storage ring.

WEPEA013

Electron Cloud Studies for the Upgrade of the CERN PS

electron, extraction, simulation, proton

2522

G. Iadarola
Naples University Federico II, Science and Technology Pole, Napoli, Italy
H. Damerau, S.S. Gilardoni, G. Iadarola, S. Rioja Fuentelsaz, G. Rumolo, G. Sterbini, C. Yin Vallgren
CERN, Geneva, Switzerland
M.T.F. Pivi
SLAC, Menlo Park, California, USA

The observation of a significant dynamic pressure rise as well as measurements with dedicated detectors indicate that an electron cloud develops in the CERN PS during the last stages of the RF manipulations for the production of LHC type beams, especially with 25ns bunch spacing. Although presently these beams are not degraded by the interaction with the electron cloud, which develops only during few milliseconds before extraction, the question if this effect could degrade the future high intensity and high brightness beams foreseen by the LHC Injectors Upgrade (LIU) project is still open. Therefore several studies are being carried out employing both simulations and measurements with the electron cloud detectors in the machine. The aim is to develop a reliable electron cloud model of the PS vacuum chambers in order to identify possible future limitations and find suitable countermeasures.

WEPEA018

Further Improvement of the PTC-ORBIT Code to Model Realistic Operation of High-beam Power Synchrotrons

injection, resonance, quadrupole, extraction

2534

A.Y. Molodozhentsev, E. Forest
KEK, Ibaraki, Japan

The combined PTC-ORBIT code has been developed a few years ago to study the dynamics of the high intensity proton beams in synchrotrons, including the nonlinear machine resonances and the space charge effects in the self-consistent manner. In order to extend the code abilities the time variation of the main elements of the synchrotron has been introduced into the PTC module of the code. This feature opens the direct way to model the multi-turn injection process and the slow extraction process by using realistic machine description, in particular the dynamic variation of the betatron tunes, strength of the bump magnets, dynamic resonance correction or resonance excitation. To demonstrate the code abilities the corresponding simulations for CERN PS Booster and for J-PARC Main Ring are discussed.

WEPEA031

Slow extraction design in HIMM

extraction, septum, emittance, resonance

2567

J. Shi, W.P. Chai, J.W. Xia, J.C. Yang, Y.J. Yuan
IMP, Lanzhou, People's Republic of China

A heavy ion medical machine(HIMM) is proposed for cancer therapy in Lanzhou, China. The slow extraction design of the synchrotron is introduced in this paper. Eight sextupoles are used, four of them are for correcting the chromaticity and the rest for driving the 3rd-order resonance. In order to save the aperture of vacuum chamber, a 3-magnet bump is adopted during the extraction process. The phase space map in the entrance of the electrostatic septum and the last 3 turns' particle trajectory before particle extraction are given.

WEPEA036

Spin Tune Decoherence Effects in Electro- and Magnetostatic Structures

betatron, sextupole, acceleration, emittance

2579

Y. Senichev, R. Maier, D. Zyuzin
FZJ, Jülich, Germany
N.V. Kulabukhova
St. Petersburg State University, St. Petersburg, Russia

In Electric Dipole Moment search experiments with polarized beams the coherence of spin oscillations of particles has a crucial role. The decoherent effects arise due to spin tune dependence on particle energy and particle trajectory in focusing-deflecting fields. They are described through the n-th order spin tune aberrations. Since the first order is suppressed by RF field, the second order plays crucial role. It depends on the orbit lengthening and on the odd order field components. We consider the spin decoherence effects and methods of their compensation in different channels, electrostatic, magnetostatic linking the decoherence effects with common characteristics such as the momentum compaction factor, the chromaticity and others.

WEPEA055

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

resonance, simulation, controls, 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.

WEPEA064

SixTrack-Fluka Active Coupling for the Upgrade of the SPS Scrapers

coupling, simulation, injection, luminosity

2657

A. Mereghetti, F. Cerutti, R. De Maria, B. Goddard, V. Kain, M. Meddahi, O. Mete, Y. Papaphilippou, D. Pastor Sinuela, V. Vlachoudis
CERN, Geneva, Switzerland
R. Appleby
UMAN, Manchester, United Kingdom

The LHC Injectors Upgrade (LIU) Project aims at upgrading the systems in the LHC injection chain, to reliably deliver the beams required by the High-Luminosity LHC (HL-LHC). Essential for the clean injection into the LHC, the SPS scrapers are one of the important systems under revision. In order to take into account of the effect of betatron and longitudinal beam dynamics on energy deposition patterns, and nuclear and Coulomb scattering in the absorbing medium onto loss patterns, the SixTrack and Fluka codes have been coupled, profiting from the best of the refined physical models they respectively embed. The coupling envisages an active exchange of tracked particles between the two codes at each turn, and an on-line aperture check in SixTrack, in order to estimate the local cleaning inefficiency of the system. Knob-like, time-dependent strengths have been implemented in SixTrack, since the designed scraper system foresees the use of a magnetic bump. The study is intended to assess the robustness of the proposed scraper as well as its effectiveness with respect to the desired performance.

WEPEA073

A 180 MeV Injection Upgrade Design for the ISIS Synchrotron

injection, space-charge, simulation, acceleration

2678

J.W.G. Thomason, D.J. Adams, B.S. Drumm, D.J.S. Findlay, I.S.K. Gardner, M.C. Hughes, S.J.S. Jago, B. Jones, R.J. Mathieson, S.J. Payne, B.G. Pine, A. Seville, H. V. Smith, C.M. Warsop, R.E. Williamson
STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
J. Pasternak
STFC/RAL, Chilton, Didcot, Oxon, United Kingdom
D.C. Plostinar, C.R. Prior, G.H. Rees
STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom

ISIS is the spallation neutron source at the Rutherford Appleton Laboratory in the UK. Obsolescence and reliability issues are motivating plans to replace the present 70 MeV H minus linac, and this paper presents an overview of a design to allow injection of beam into the present ISIS ring at 180 MeV, which would increase intensity as a result of reduced space charge and optimised injection. The key topics addressed are design of the injection straight, injection painting and dynamics, foil specifications, acceleration dynamics, transverse space charge, instabilities, RF beam loading and activation.

WEPFI003

A New Timing System and Electron Gun Modulator

gun, electron, linac, simulation

2705

A.S. Setty, A.S. Chauchat, D. Fasse, D. Jousse
Thales Communications & Security (TCS), Gennevilliers Cedex, France

In the last decade, Thales Communications & Security has manufactured turnkey linacs for the SOLEIL, ALBA and BESSY II synchrotrons. In the meanwhile, a new timing system and electron gun modulator was designed and a gun pulse length of 600 ps was measured. This paper will describe the system and will present the beam dynamics simulations results, comparing them with those obtained with the previous gun modulator *.
* A. Setty, "Beam dynamics of the 100 MeV preinjector for the Spanish synchrotron ALBA", PAC07, Albuquerque, USA, June 2007.

WEPFI021

Influence of Core Winding Tension and Ribbon Quality on the MA Core RF Characteristics

impedance, vacuum, factory, cavity

2747

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

J-PARC 3 GeV Rapid Cycling Synchrotron (RCS) and Main Ring (MR) employ RF cavities loaded with Magnetic Alloy (MA) cores to generate a high field gradient. To achieve the high field gradient, the core shunt impedance is a key parameter. We found during the development of MA cores for RCS RF cavities that the core shunt impedance was increased by lowering a core winding tension. We lowered the core winding tension in order to improve the electrical insulation between MA ribbon layers. The lower winding tension reduced the core filling factor that is defined as the volume ratio of MA ribbons and geometrical dimensions. The core shunt impedance might be reduced according to the core filling factor reduction. We discuss the reason why the lower winding tension increased the core shunt impedance. We also report the influence of the ribbon quality variation on the MA core RF characteristics.

WEPFI022

Inner Diameter Change over the Years of MA Cores of RF-cavities at the J-PARC 3 GeV Synchrotron

cavity, gun

2750

T. Shimada, M. Nomura, F. Tamura, M. Yamamoto
JAEA/J-PARC, Tokai-mura, Japan
K. Hara, K. Hasegawa, C. Ohmori, M. Toda, M. Yoshii
KEK, Tokai, Ibaraki, Japan
A. Schnase
GSI, Darmstadt, Germany
H. Suzuki
Japan Atomic Energy Agency (JAEA), International Fusion Energy Research Center (IFERC), Rokkasho, Kamikita, Aomori, Japan

The 11 RF cavities at the J-PARC 3 GeV synchrotron use 198 MA cores. Buckling occurred in some cores since the operation started in October 2007. We have measured the inner diameters of the cores as part of the investigation to determine the cause of buckling when the cavities were disassembled for maintenance. We obtained inner diameter change values of 36 cores over a longer than 2 years interval in the summer of 2012. We noticed deformations of the inner shapes of the cores related to the manufacturing process, and that inner diameter changes over this period were not detected in most of the cores without buckling. Furthermore, an effective core manufacturing process to avoid the buckling has been established. We are going to replace old type cores with new type cores in summer shutdown periods every year and will have finished the replacement work by the summer of 2013. We report the relation between inner shapes of the cores and the manufacturing process and inner shape changes over the years.

WEPFI028

RF System of the CSNS Synchrotron

cavity, controls, LLRF, feedback

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.

WEPFI033

Development of the HLS 40kW Solid State Amplifier

rf-amplifier, power-supply, storage-ring, damping

2777

L. Lin, G. Huang, C. Li, Y.T. Liu, W. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China

A 40kW RF Solid State Amplifier (SSA) will replace the 25kW tetrode amplifier as the new RF power generator of HLS 800MeV electron storage ring. This SSA contains sixty-five 650W amplifier units (one unit drives sixty-four’s), with two-stage combination to reach the 40kW output. All of the components of SSA are prepared and tested, each of them meets the design requirements. The SSA has been assembled, and is in off-line testing now. The process of SSA’s design and manufacture, and the test results are presented in this paper.

WEPFI049

CoStub: A 6 1/8” Coaxial Short Circuit using Stubs

cavity, simulation, background, high-voltage

2809

B. Bravo, F. Mares, F. Pérez
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

ALBA is a 3Gev synchrotron light source located in Barcelona and operating with users since May 2012. The ALBA storage ring uses six room temperature cavities; each one fed by two 80kW IOTs amplifiers at 499.654 MHz. The power of the pair of transmitters is combined by a cavity combiner, CaCo. The two possible operation modes of CaCo at high power have been tested. The symmetrical mode (two IOTs feed the CaCo symmetrically) works properly and without presenting any problem. But in the asymmetrical mode (one IOT feeds the CaCo and the other is keeping passive) a standing wave is created between the passive IOT and Caco, provoking a large voltage in the gap of the passive IOT that broke the ceramic. A new device, CoStub (coaxial stub), to short circuit the coaxial waveguide of the passive arm and protects the passive IOT has been built and successfully tested. This paper presents the design details and the low level and high power test of this device.

WEPFI063

Progress on the ISIS Synchrotron Low Power RF System Upgrade

controls, cavity, 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.

WEPME003

Determination of Optics Transfer between the Kicker and BPMs for Transverse Feedback System

kicker, feedback, betatron, optics

2923

M. Alhumaidi, A.M. Zoubir
TU Darmstadt, Darmstadt, Germany
J. Grieser
TU Darmstadt, RTR, Darmstadt, Germany

The knowledge of the transfer optics between the positions of the Kicker and the BPMs is required for the calculation of the correction signal in transverse feedback systems. Therefore, using nominal values of the transfer optics with uncertainties leads to feedback quality degradation, and thus beam disturbances. In this work, we propose a method for measuring the phase advances and amplitude scaling between the positions of the kicker and the BPMs. Directly after applying a kick on the beam by means of the kicker, we record the BPM signals. Consequently, we use the Second-Order Blind Identification (SOBI) algorithm to decompose the noised recorded signals into independent sources mixture. Finally, we determine the required optics parameters by identifying and analyzing the betatron oscillation sourced from the kick based on its mixing and temporal patterns. Results for the heavy ions synchrotron SIS 18 at the GSI are shown.

WEPME004

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

controls, cavity, 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

WEPME010

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

feedback, ion, controls, 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.

WEPME023

Study of the Vibration of the AC Dipole and Magnetic Measurement Girder for CSNS/RCS

dipole, acceleration, resonance, damping

2980

R.H. Liu, L. Kang, H. Qu, G.Y. Wang, H.J. Wang, J. S. Zhang
IHEP, Beijing, People's Republic of China

The dipole magnet of the China Spallation Neutron Source Rapid-cycling Synchrotron (RCS) will be operated at a 25Hz sinusoidal alternating current which causes severe vibration. The vibration will influence the long-term safety and reliable operation of the magnet. By taking the magnet and magnetic measurement girder as a specific model system, a method for analyzing and studying the dynamic characteristic of the system is put forward by combining theoretical calculation with experimental testing. And the ctive vibration of magnet is different with passive vibration which was causes by ground vibration, so a new isolator was designed to decrease the vibratory force and avoid the resonance phenomenon.

WEPME025

The Surveying Data Processing of Control Network based on HLS Upgrade

controls, survey, 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.

WEPME027

Analysis of Tidal Effects on Measurement Accuracy of HLS

alignment, site, synchrotron-radiation, radiation

2989

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

Funding: Natural Science Foundation of China
HLS* is mainly used in survey and high-accuracy alignment in particle accelerator. Monitoring the earth tides is primarily introduced in this paper. Based on the earth tide theory and the ocean load effects on the planet earth, the tidal effects on a hydrostatic leveling system is analyzed. Finally, the local ground deformation is obtained,and the current research establish a foundation for the further study.
HLS-hydrostatic levelling system

WEPME033

Status of SSRF Fast Orbit Feedback System

feedback, EPICS, power-supply, controls

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.

WEPME048

Adjusting and Calibration Method for TPS Laser PSD System

laser, alignment, factory, storage-ring

3037

M.L. Chen, J.-R. 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, M.H. Wu
NSRRC, Hsinchu, Taiwan
J.-R. Chen
National Tsing Hua University, Hsinchu, Taiwan

Laser PSD positioning system is a part of the TPS girder auto-alignment system and is designed for aligning and positioning the straight-section girders of TPS storage ring. Although the components of Laser PSD system are fabricated, assembling and adjusting precisely in advance, the accuracy of Laser PSD system is still influenced by girder fabricating quality, assembling errors and moving errors by transportation. For system correction, Laser beam positions on four sets of PSDs are formulized as an equation and calibrated with Laser tracker ultimately. According to the PSD calibration formula, the two girders of 18m long straight-section can be aligned and positioned within 20um by comparing with Laser tracker. This paper describes the assembly, installation and calibration process of Laser PSD system.

WEPME055

Investigation of Source Point Instabilities in Dipole Magnet Based Beamlines

dipole, feedback, optics, radiation

3055

M. Apollonio, R. Bartolini
Diamond, Oxfordshire, United Kingdom
R. Bartolini
JAI, Oxford, United Kingdom

At Diamond the source point in the second dipole of the Double Bend Achromats can vary due the lack of adjacent BPMs constraining angle and position of the electron beam at the dipole. We have implemented a code based on our AT model to predict the effects of a corrector strength change and compared our predictions to data both from a beamline and from our pinhole cameras. We discuss the possibility of interfacing the code to a ray tracing routine in order to infer beam spot changes in the downstream beamline and suggest a procedure to restore the original source point.

THXB101

High Power Operation and Beam Instrumentations in J-PARC Synchrotrons

extraction, beam-losses, quadrupole, proton

3085

T. Toyama
J-PARC, KEK & JAEA, Ibaraki-ken, Japan

Beam monitors developed and utilized at MR and RCS of J-PARC will be presented with emphasis on special characteristics for high intensity proton accelerator. Achieved beam characteristics and approach to improve beam intensity will be described in connection with the beam monitors. Usage of a transverse RF field to improve a duty factor of the slow extracted beam will be presented.

Slides THXB101 [16.387 MB]

THXB201

Novel Techniques and Challenges in Hadron Therapy

ion, proton, cyclotron, extraction

3112

Th. Haberer, E. Feldmeier, M. Galonska, A. Peters, C. Schömers
HIT, Heidelberg, Germany

This talk should review novel techniques and challenges for beam delivery systems with various beam scanning methods (such as 3D scanning, 4D scanning and so on) to conform the beam dose to the tumor shape in proton and carbon ion therapy, as developed by PSI, GSI, HIMAC, IMP etc. Besides traditional accelerators such as cyclotrons and synchrotrons, the talk should review the technical challenges and prospects for future compact hadron therapy accelerators such as DWA, laser accelerators and so on.

Slides THXB201 [4.934 MB]

THPPA03

The Development of China’s Accelerators I Have Experienced

proton, luminosity, linac, radiation

3144

S.X. Fang
IHEP, Beijing, People's Republic of China

The development of China’s high energy accelerator for half a century falls into two stages, namely the first 20 hovering years (1958-1978) and the later 30 years of rapid development (from 1978 till now). I was lucky enough to have experienced the whole process, witnessed, and to some extent, joined in the decision-making, the projects approval, the designing, the development and construction of China's five large scientific facilities undertaken by the Institute of High Energy Physics in Beijing. A brief review is given of the previous stage of history regarding the consideration of China’s high energy accelerators in the first 20 years. A short presentation is also given of the later 30 years concerning the rapid development of the Beijing Electron-Positron Collider (BEPC and BEPCII), the completed BEPC-based Shanghai Synchrotron Radiation Facility (SSRF), the Chinese Spallation Neutron Source (CSNS) under construction, the high-intensity proton accelerator (ADS) used for nuclear waste transmutation and the proton therapy machine in the R&D stage.

Slides THPPA03 [6.015 MB]

THPEA002

The Accelerator Control System at ELSA

controls, diagnostics, electron, 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

controls, 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.

THPEA015

Induced Radioactivity Research for Scraper

electron, radioactivity, linac, radiation

3173

L.J. He, Y.K. Chen, W. Li
USTC/NSRL, Hefei, Anhui, People's Republic of China

The 200MeV electron linac of NSRL is one of the earliest high-energy electron linear accelerators in China. The electrons are accelerated to 200MeV by five accelerating tubes and collimated by the scraper followed each accelerating tube. The scraper aperture is smaller than the accelerating tube,so some electrons will hit on the structure materials when they pass through them. These lost electrons will cause induced radioactivity due to bremsstrahlung, cascade shower and photo-nuclear reaction. This paper gives the simulation to different energy electrons lost at the corresponding scraper by EGSnrc. The results showed that electrons were lost mainly at the scraper during the accelerating period,and the actual measurement confirmed this. Meanwhile,the induced radionuclide types have been studied. Recently,the linac mentioned above has been retired because of upgrading. The equipments and materials removed are used to study induced radioactivity generated in different materials. The research will provide the theoretical basis for the similar accelerator decommissioning plan,and is also significant for accelerator structure design,material selection and radiation protection programs design.

THPEA041

Performance Improvements of the SPS Internal Beam Dump for the HL-LHC Beam

kicker, vacuum, proton, dumping

3231

F.M. Velotti, O. Aberle, C. Bracco, E. Carlier, P. Chiggiato, J.A. Ferreira Somoza, B. Goddard, M. Meddahi, V. Senaj, J.A. Uythoven
CERN, Geneva, Switzerland

The SPS internal beam dump has been designed for beam specifications well below the HL-LHC ones, and for modes of operation which may not be adequate for the HL-LHC era. The present system suffers from several limitations in the allowed intensity and energy range, and its vacuum performance affects nearby high-voltage kicker systems. In this report the limitations of the internal beam dump system are reviewed, and the possible improvements compared. Preliminary upgrade proposals are presented, taking into consideration the expected operational HL-LHC parameters.

THPEA046

Machine Protection at the LHC - Experience of Three Years Running and Outlook for Operation at Nominal Energy

injection, feedback, extraction, optics

3246

D. Wollmann, R. Schmidt, J. Wenninger, M. Zerlauth
CERN, Geneva, Switzerland

With above 22fb-1 integrated luminosity delivered to the experiments ATLAS and CMS the LHC surpassed the results of 2011 by more than a factor 5. This was achieved at 4TeV, with intensities of ~2e14p per beam. The uncontrolled loss of only a small fraction of the stored beam is sufficient to damage parts of the sc. magnet system, accelerator equipment or the particle physics experiments. To protect against this a correct functioning of the complex LHC machine protection (MP) systems through the operational cycle is essential. Operating with up to 140MJ stored beam energy was only possible due to the experience and confidence gained in the two previous running periods, where the intensity was slowly increased. In this paper the 2012 performance of the MP systems is discussed. The strategy applied for a fast, but safe, intensity ramp up and the monitoring of the MP systems during stable running periods are presented. Weaknesses in the reliability of the MP systems, set-up procedures and setting adjustments for machine development periods, discovered in 2012, are critically reviewed and improvements for the LHC operation after the up-coming long shut-down of the LHC are proposed.

THPEA049

Implementation of the EPICS Data Archive System for the TPS Project

EPICS, controls, GUI, 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.

THPFI014

Bellows with a New RF Shield Made of Metal Braid for High Intensity Proton Accelerators

impedance, vacuum, background, coupling

3321

N. Ogiwara, J. Kamiya, M. Kinsho, Y. Shobuda
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
O. Koizumi
Sun-Tech limited, Kobe, Japan

In the 3 GeV-RCS (Rapid cycling Synchrotron) in J-PARC (Japan Accelerator Research Complex) project, large-scale hydro-formed bellows were developed to adjust the gap between the ceramic ducts and/or between the ceramic ducts and the transport ducts. They have been equipped with a newly developed RF shield, because the usual beryllium-copper spring finger contacts were found to be very hard (roughly 1000 N/mm) owing to the large size. This contact is made of Ti braid, which consists of wires with a diameter of 0.3 mm. This RF contact is a kind of basket (with two ports) made with the braids. Because of the spring effect, the contact can change shape easily. In addition, the contact can easily connect the different cross sections in a smooth fashion. Furthermore, this structure is almost free from the dust generation, which is one of the most troublesome problems for the usual spring finger contacts. This time, we have constructed reserve bellows with the RF shield made of SUS 316L wires to improve the reliability of user operation. The outline of the bellows will be presented, especially laying emphasis on the mechanical function of the RF shield.

THPFI016

DESIGN CONSIDERATION OF BEAM DUCTS FOR QUADRUPOLE CORRECTORS IN J-PARC RCS

quadrupole, vacuum, injection, focusing

3327

J. Kamiya, N. Hayashi, H. Hotchi, M. Kinsho, N. Ogiwara, N. Tani, Y. Watanabe
JAEA/J-PARC, Tokai-mura, Japan

which rapidly correct the tunes, are planned to be installed during the summer shutdown in 2013. The characteristic of the excitation pattern of such quadrupoles (quadrupole corrector) is their fast change of magnetic field, which are more than 200T/s at the fastest point. In this report, we describe a deliberation flow about the design of a vacuum chamber, which is installed in the quadrupole corrector. The effect of eddy current was calculated in the case of the current titanium vacuum chamber. The results showed that the temperature rise was too much (up to ~350oC) and the magnetic field in the vacuum chamber is largely distorted by the eddy current. Therefore we decided to employ an alumina ceramics vacuum chamber, for which we have a past achievement in RCS*. We estimated the displacement and stress, which is caused by the atmospheric pressure, for the alumina ceramics vacuum chamber and vacuum component around it by making the calculation model for the finite element method. It was found that there was no large displacement and stress by installing the alumina ceramics vacuum chamber.
*M. Kinsho, et al. Vacuum 81 (2007) 808.

THPFI024

Application of Electropolishing in CSNS/RCS Primary Collimator Scrapers

cathode, collimation, proton, scattering

3348

L. Kang, Z.X. He, H. Qu, J.B. Yu, Y.Q. Zou
IHEP, Beijing, People's Republic of China

According to the requirements for the beam collimation system physical design of the rapid cycling synchrotron (RCS) of China Spallation Neutron Source (CSNS) , the primary collimator scrapers are made of 0.17±0.005mm thickness tungsten sheets. The machining of the tungsten sheet is very difficult because of high hardness and characteristics of the intrinsic brittleness of tungsten. In this paper, electropolishing processing methods is used for tungsten sheets processing. A special electropolishing device is designed according to the principle and process of electropolishing. The processing of tungsten sheets are finally completed after a series of experiments. And the rules of electropolishing for tungsten sheet processing are obtained according to the experimental results.

THPFI031

Development of Beam Collimators for the 1.6 GeV Rapid Cycling Synchrotron of CSNS

collimation, vacuum, simulation, shielding

3364

J.B. Yu, pf.He. He, L. Kang, H. Qu, Y.Q. Zou
IHEP, Beijing, People's Republic of China

In order to reduce the uncontrolled losses in the localized station, the beam collimation system has been performed for the 1.6GeV synchrotron of CSNS. The CSNS/RCS transverse collimation system is designed to be a two-stage system which consists of one primary collimator and four secondary collimators. Much work about machinery design and manufacture of the collimation system has been done till now. This paper will show the exterior frame of collimation system by considering the physical demands and spatial position. Then the progress which contains design and machining of collimators will also be introduced. Finally some problems which are mainly about the design of secondary collimators will be mentioned.

THPFI044

NEG Thin Film Coating Development for the MAX IV Vacuum System

vacuum, cathode, plasma, synchrotron-radiation

3385

M.J. Grabski, J. Ahlbäck, E. Al-Dmour, P.F. Tavares
MAX-lab, Lund, Sweden
S. Calatroni, P. Chiggiato, P. Costa Pinto, M. Taborelli
CERN, Geneva, Switzerland

The new synchrotron radiation facility of the MAX IV laboratories is under construction and expected to deliver the first light beam in 2016. To cope with the small aperture, the intense photon bombardment and the low-pressure requirement, most of the beam pipes for the 3-GeV ring are going to be coated with Ti-Zr-V non-evaporable getter (NEG) thin films. To take advantage from the experience acquired during the construction of the Large Hadron Collider (LHC), collaboration between CERN and MAX IV Laboratories has been set up. The choice of the extruded Cu tubes, the preliminary surface treatments, the coating configuration, and the performance validation of the small-diameter vacuum chambers have been addressed. In parallel, an intense development has been tackled at CERN for the coating of vacuum chambers where photon and electron beams circulate in separate pipes. The most important results of the collaboration are presented and future perspectives pointed out.

THPFI066

Performance Enhancement of Electrical Power System at NSRRC

controls, radio-frequency, 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, controls, booster, status

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

controls, 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, controls, photon, PLC

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.

THPFI072

Heat Transfer Analysis of a Water-cooled Channel for the TPS Front End Components

simulation, synchrotron-radiation, radiation, insertion

3466

C.K. Kuan, J.-R. Chen, Y.T. Cheng, J.Y. Chuang, H.Y. Lin, P.A. Lin, Y.K. Liu, I.C. Sheng, T.C. Tseng
NSRRC, Hsinchu, Taiwan
J.-R. Chen
National Tsing Hua University, Hsinchu, Taiwan

The masks, absorbers and slits must withstand the extremely high power and power density in the TPS front end. The material always used is OFHC or Glidcop. One solution is to increase the cooling efficiency of the water-cooled channel in these components. With the restrictions of water pressure < 7 kg/cm² and water flow velocity < 3 m/s, the wire coil is chosen to enhance the average heat- transfer coefficient and increase not too much the loss of water pressure. With a water channel of diameter 7.5 mm and wire coil inserts of pitch 7.5 mm and wire diameter 1 mm, the cooling efficiency becomes enhanced 1.4 to 2 times in the components of the TPS front end. The wire coils of varied pitches are simulated and calculated in this work. We also compare our investigated data with other experimental data of other authors.

THPFI075

Baking Test for an In-vacuum Undulator

vacuum, undulator, controls, 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.

THPFI079

Start-up of the NESTOR Facility Vacuum System

vacuum, storage-ring, electron, ion

3478

A.Y. Zelinsky, A.N. Gordienko, V.A. Grevtsev, I.I. Karnaukhov, I.M. Karnaukhov, N.I. Mocheshnikov, A. Mytsykov, V.L. Skirda
NSC/KIPT, Kharkov, Ukraine

The Kharkov X-ray generator NESTOR based on Compton backscattering is under commissioning. The vacuum system of the complex integrates a linear accelerator-injector, the beam transport channel and the electron storage ring with energy range from 40 to 225 MeV. Elements of vacuum chambers, pumping facilities, cleaning surfaces procedures are described. Chambers are made of stainless steel (SS). After vacuum pretesting pressure 5 × 10^-9 Torr in the storage chambers ring achieved.

THPME001

Permanent Magnets in Accelerators can save Energy, Space, and Cost

permanent-magnet, dipole, quadrupole, vacuum

3511

F. Bødker, L.O. Baandrup, A. Baurichter, N. Hauge, K.F. Laurberg, B.R. Nielsen, G. Nielsen
Danfysik A/S, Taastrup, Denmark
O. Balling
Aarhus University, Aarhus, Denmark
F.B. Bendixen, P. Kjeldsteen, P. Valler
Sintex A/S, Hobro, Denmark
S.P. Møller, H.D. Thomsen
ISA, Aarhus, Denmark
H.-A. Synal
ETH, Zurich, Switzerland

Green Magnet technology with close to zero electrical power consumption without the need for cooling water saves costs, space and hence spares natural resources. A compact dipole based on permanent magnets has been developed at Danfysik in collaboration with Sintex and Aarhus University. This first Green Magnet has been delivered to ETH Zurich for testing in a compact accelerator mass spectrometer facility. Permanent NdFeB magnets generate a fixed magnetic field of 0.43 T at a gap of 38.5 mm without using electrical power in the H-type 90° bending magnet with a bending radius of 250 mm. Thermal drift of the permanent magnets is passively compensated. Small air cooled trim coils permit fine tuning of the magnetic field. Magnetic field measurements and thermal stability tests show that the Green Magnet fully meets the magnetic requirements of the previously used electromagnet. The use of Green Magnet technology in other accelerator systems like synchrotron light sources is discussed.

THPME003

Standard Sextupole Magnets for NSLS-II Synchrotron

sextupole, dipole, booster, target

3517

C.W.O. Ostenfeld, N. Hauge, P. Ladefoged
Danfysik A/S, Taastrup, Denmark

Danfysik received the order to design, manufacture and test 169 Standard Sextupole Magnets for the NSLS-2 synchrotron. Extraordinary tight tolerances were specified for the mechanical and magnetic properties. We present a re-optimized magnetic pole profile to make a more mechanically robust design, suitable for large-scale manufacture. Due to a well-controlled wire erosion process during the manufacturing stage, the mechanical tolerances were kept on the 10 micron level, even after assembly/disassembly cycles. A major challenge of the project was to verify the magnetic performance of the magnets. This was done using our in-house harmonic measurement bench. We present magnetic measurements of the magnet series, measured over more than 24 months, which show high stability, both in terms of magnetic roll angle, error field terms, and integrated strength.

THPME021

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

multipole, controls, undulator, quadrupole

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.

THPME039

The Control System for the Purification Station at NSRRC

cryogenics, controls, monitoring, vacuum

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.

THPWO056

A 5.3 MeV/U, 200MHz APF DTL for Carbon Ions as an Injector of Medical Synchrotron

focusing, cavity, emittance, DTL

3890

P. Jiang, Y.J. Yuan
IMP, Lanzhou, People's Republic of China

A new low energy medium frequency DTL for 12C⁵⁺ with alternative phase focusing method (APF), which has advantage in compact space and low cost, was designed as an injector of medical synchrotron. There is no conventional focusing elements in the APF DTL, and transversal focusing is realized using RF field by varying synchronous phase instead. The envelopes of beam size are presented and the emittance change of six-dimension phase space is shown. The simple method proposed by Y. Iwata was used to create synchronous phase array. Since the motion between transversal and longitudinal plains are coupled, the longitudinal acceptance of the DTL is not large.

FRYAA01

An Overview of Light Source Development in Asia

FEL, radiation, electron, linac

4005

D. Wang
SINAP, Shanghai, People's Republic of China

This talk should cover the history of light sources that have been constructed, are now in operation or planned for the future in Asia. Advances in accelerator physics and technological innovations leading to steadily increasing machine performance and photon beam properties should be discussed.

Slides FRYAA01 [7.342 MB]