IPAC2013 - List of Keywords (synchrotron-radiation)

Paper	Title	Other Keywords	Page
MOPEA019	Studies of Bunch-bunch Interactions in the ANKA Storage Ring with Coherent Synchrotron Radiation using an Ultra-fast Terahertz Detection System	radiation, synchrotron, storage-ring, wakefield	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, synchrotron, storage-ring, electron	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.

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

MOPME039	A New Method of Acquiring Fast Beam Transversal Profile in the Storage Ring	synchrotron, factory, electron, 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.

MOPME053	Point Spread Function Study of X-ray Pinhole Camera in SSRF	radiation, synchrotron, 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	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	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.

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

MOPWA073	A Turn-by-turn Beam Profile Monitor using Visible Synchrotron Radiation at CESR-TA	electron, synchrotron, 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, synchrotron, simulation, polarization	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.

MOPWO037	SixTrack Simulation of Off-momentum Cleaning in LHC	simulation, radiation, synchrotron, betatron	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.

TUPWO061	Design of a Soft Orbit Bump for FEL Mirror Protection at Duke FEL/HIGS Facility	FEL, radiation, electron, synchrotron	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.

WEPWA006	Beam Heat Load Measurements with COLDDIAG at the Diamond Light Source	electron, synchrotron, 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, synchrotron, vacuum, 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.

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

THPFI044	NEG Thin Film Coating Development for the MAX IV Vacuum System	vacuum, cathode, plasma, synchrotron	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, synchrotron, power-supply	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.

THPFI069	Power Saving Status in the NSRRC	controls, synchrotron, 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.

THPFI072	Heat Transfer Analysis of a Water-cooled Channel for the TPS Front End Components	simulation, synchrotron, 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	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.

Paper

Title

Other Keywords

Page

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

radiation, synchrotron, storage-ring, wakefield

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, synchrotron, storage-ring, electron

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.

MOPEA044

Maintenance Experience for Personnel Safety System at SSRF

controls, PLC, radiation, synchrotron

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.

MOPME039

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

synchrotron, factory, electron, 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.

MOPME053

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

radiation, synchrotron, 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

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

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.

MOPWA019

Digital Power Supply Controller Development Based on FPGA

power-supply, controls, booster, synchrotron

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.

MOPWA073

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

electron, synchrotron, 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, synchrotron, simulation, polarization

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.

MOPWO037

SixTrack Simulation of Off-momentum Cleaning in LHC

simulation, radiation, synchrotron, betatron

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.

TUPWO061

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

FEL, radiation, electron, synchrotron

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.

WEPWA006

Beam Heat Load Measurements with COLDDIAG at the Diamond Light Source

electron, synchrotron, 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, synchrotron, vacuum, 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.

WEPME025

The Surveying Data Processing of Control Network based on HLS Upgrade

controls, survey, synchrotron, 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

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

THPFI044

NEG Thin Film Coating Development for the MAX IV Vacuum System

vacuum, cathode, plasma, synchrotron

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, synchrotron, power-supply

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.

THPFI069

Power Saving Status in the NSRRC

controls, synchrotron, 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.

THPFI072

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

simulation, synchrotron, 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

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.