IPAC2012 - List of Keywords (storage-ring)

Paper	Title	Other Keywords	Page
MOYBP01	State-of-the-Art and Future Prospects in RF Superconductivity	cavity, SRF, niobium, electron	11
	K. Saito KEK, Ibaraki, Japan
	This presentation should recount the remarkable progress in improving the performance of superconducting cavities over the past 50 years and explore future directions, including advances in materials other than Nb, such as MgB2 and novel multi-layer superconductor-insulator systems. This talk should provide an overview of international activities.
	Slides MOYBP01 [10.097 MB]

MOPPC060	Investigations into Beam Life Time in Low Energy Storage Rings	ion, target, electron, antiproton	271
	A.I. Papash, A.V. Smirnov MPI-K, Heidelberg, Germany A.I. Papash JINR, Dubna, Moscow Region, Russia C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom
	Funding: Work supported by the Helmholtz Association of National Research Centers and GSI under contract VH-NG-328. In low energy storage rings, beam life time critically depends on the residual gas pressure, scattering effects caused by in-ring experiments and the available machine acceptance. A comprehensive simulation study into these effects has been realized with a focus on the TSR storage ring in Heidelberg and the electrostatic rings ELISA, the AD recycler and the ultra-low energy storage ring (USR). This was done by using the computer code BETACOOL in combination with the OPERA-3D and MAD-X programs. In this contribution, the results from these studies are presented and compared to available experimental data. Based on these simulations, criteria for stable ring operation are then presented.

MOPPC078	Simulation Studies of Injection Scheme in TPS Storage Ring	injection, lattice, simulation, alignment	316
	Y.C. Lee, H.-P. Chang, P.J. Chou NSRRC, Hsinchu, Taiwan
	Funding: NSRRC, Hsinchu, Taiwan. The baseline lattice of TPS storage ring was finalized in October 2009. Later upon users’ request, we plan to implement the double mini-βy lattice in three 12-m straight sections of TPS storage ring. These locations were chosen to maintain the symmetry of the storage ring lattice. Particle tracking for the first few turns were used to check the injection scheme of storage ring, including errors introduced in manufacturing and installation process. Results of simulation studies will be presented.

MOPPD001	Accelerator R&D in the QUASAR Group	antiproton, diagnostics, niobium, instrumentation	364
	C.P. Welsch Cockcroft Institute, Warrington, Cheshire, United Kingdom C.P. Welsch The University of Liverpool, Liverpool, United Kingdom
	Funding: Work supported by the Helmholtz Association and GSI under contract VH-NG-328, the EU under contracts PITN-GA-2008-215080, PITN-GA-2011-289191, PITN-GA-2011-289485 and STFC. The QUASAR Group was founded in 2007 with an initial focus on the development and experimental exploitation of a novel electrostatic ultra-low energy storage ring (USR), part of the future facility for low-energy antiproton and ion research (FLAIR). The group's research activities have grown considerably over the past four years and now include also the development of beam diagnostic tools for accelerators and light sources, investigations into superconducting linear accelerators and medical applications, and, most recently, a broad R&D program into laser applications at accelerators. In this contribution, an overview of the QUASAR Group’s research achievements to date is given.

MOPPD002	Ultra-low Energy Storage Ring at FLAIR	extraction, antiproton, ion, lattice	367
	C.P. Welsch, D. Newton, M.R.F. Siggel-King Cockcroft Institute, Warrington, Cheshire, United Kingdom O.E. Gorda, O. Karamyshev, G.A. Karamysheva, M. Panniello, A.I. Papash, A.V. Smirnov MPI-K, Heidelberg, Germany J. Harasimowicz, M. Putignano, C.P. Welsch The University of Liverpool, Liverpool, United Kingdom
	Funding: The support of the HGF and GSI under contract VH-NG-328, the EU under contract PITN-GA-2008-215080, the Max Planck Institute for Nuclear Physics and the STFC Grant ST/G008248/1 is acknowledged. The Ultra-low energy electrostatic Storage Ring (USR) at the future Facility for Low-energy Antiproton and Ion Research (FLAIR) will provide cooled beams of antiprotons in the energy range between 300 keV down to 20 keV. Based on the original design concept developed in 2005, the USR has been completely redesigned over the past few years. The ring structure is now based on a 'split achromat' lattice. This ensures compact ring dimensions of 10 x 10 m, whilst allowing both, in-ring experiments with gas jet targets and studies with extracted beams. In the USR, a wide range of beam parameters will be provided, ranging from very short pulses in the nanosecond regime to a coasting beam. In addition, a combined fast and slow extraction scheme was developed that allows for providing external experiments with cooled beams of different time structure. Furthermore, studies into beam diagnostics methods for the monitoring of ultra-low energy ions at beam intensities less than 10⁶ were carried out. Here, we present the USR design with an emphasis on the expected beam parameters available to the experiments at FLAIR.

MOPPD071	Error Localization in RHIC by Fitting Difference Orbit	feedback, closed-orbit, dipole, optics	526
	C. Liu, M.G. Minty, V. Ptitsyn BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. Many errors in an accelerator are evidenced as transverse kicks to the beam, which distort the beam trajectory. Therefore, the information of the errors are imprinted in the distorted orbits, which are different from what would be predicted by the optics model. In this paper, we introduce an algorithm for fitting the orbit based on an on-line optics model. We apply the algorithm to localize the location of the elusive source of vertical diurnal variations observed in RHIC, and analyze D0/Dx errors in local coupling measurement.

MOPPP004	Further Study on Fast Cooling in Compton Storage Rings	laser, electron, simulation, photon	571
	E.V. Bulyak NSC/KIPT, Kharkov, Ukraine J. Urakawa KEK, Ibaraki, Japan F. Zimmermann CERN, Geneva, Switzerland
	Compton sources can produce gamma-ray photons of ultimate intensity, but suffer from the large recoils experienced by the circulating electrons scattering off the laser photons. We have previously proposed a scheme called asymmetric fast cooling to reduce the beam energy spread in Compton rings. This report presents results of further studies on the fast cooling. In particular, we show that (1) a proper asymmetric setup of the scattering point results in significant reduction of the quantum losses of electrons in Compton rings with moderate energy acceptance, and (2) the optimized pulsed mode of operation in synchrotron-dominated rings enhances the overall performance of such gamma-ray sources. Theoretical results presented are in good accordance with numerical simulations. We discuss the performance of an existing storage ring such as KEK ATF DR equipped with an optical cavity and presently available laser system.

MOPPP051	NSLS-II Transport Line Progress	booster, linac, diagnostics, injection	676
	R.P. Fliller, A.T. Anderson, B. Benish, W. DeBoer, G. Ganetis, R. Heese, H.-C. Hseuh, J. Hu, M.P. Johanson, B.N. Kosciuk, D. Padrazo, K. Roy, T.V. Shaftan, O. Singh, J.L. Tuozzolo, B. Wahl, G.M. Wang BNL, Upton, Long Island, New York, USA
	Funding: This manuscript has been authored by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy. The National Synchrotron Light Source II (NSLS-II) is a state-of-the-art 3-GeV third generation light source currently under construction at Brookhaven National Laboratory. The NSLS-II injection system consists of a 200 MeV linac, a 3-GeV booster synchrotron and associated transfer lines. The first part of the Linac to Booster Transport (LBT) line has been installed for linac commissioning. This part includes all components necessary to commission the NSLS-II linac. The second part of this transport line is undergoing installation. Initial results of hardware commissioning will be discussed. The Booster to Storage Ring (BSR) transport line underwent a design review. The first part of the BSR transport line, consisting of all components necessary to commission the booster will be installed in 2012 for booster commissioning. We report on the final design of the BSR line along with the plan to commission the booster.

MOPPP053	Failure Mode Analysis in Preparation for Top-up Injection at the Canadian Light Source (CLS)	injection, dipole, kicker, simulation	682
	L.O. Dallin CLS, Saskatoon, Saskatchewan, Canada
	Top-up injection involves injecting beam with beamline safety shutters open. Consequently it is extremely important that no electrons enter the beamlines where they could be a potential safety hazard to beamline personnel. To investigate the likelihood that electrons could exit the storage ring various failure mode simulations have been done. The approach is to account for all possible injection trajectories and show that these particles will be intercepted by various storage ring apertures before they reach an amplitude that is deemed unsafe. This amplitude was chosen to be 50 mm and the field roll-off of all storage ring magnets were defined to this amplitude. Failure modes invested included injection kicker failures, uncorrected misalignment errors, off-energy injection and shorted storage ring magnet coils. Errors that would render it impossible to store beam were not investigated. As some particles reached amplitudes beyond the safe limit measures have been devised to eliminate these unsafe scenarios.

MOPPP054	Study of a New Injection Scheme for the SSRF Storage Ring	injection, kicker, emittance, dynamic-aperture	685
	M.Z. Zhang, B.C. Jiang, L. Ouyang, Q.L. Sun, S.Q. Tian SINAP, Shanghai, People's Republic of China
	A low emittance configuration of the SSRF storage ring had been designed and commissioned. Along with reducing the emittance, the dynamic aperture decreases quickly. It doesn’t meet aperture require of the normal injection scheme anymore and the injection efficiency is lower. The pulsed multi-pole magnets give the opportunity to overcome the smaller dynamic aperture. Pulsed quadrupole and sextupole both are study for the injection scheme. With and without the orbit bump kickers are also considered in this study. The injection scheme suggestions are presented in this paper.

MOPPP066	Calculated Spectra from Magnetic Field Measurements of 1.5 m Superconducting Undulator Coils	undulator, emittance, permanent-magnet, vacuum	711
	S. Casalbuoni, T. Baumbach, S. Gerstl, A.W. Grau, M. Hagelstein, T. Holubek, D. Saez de Jauregui Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany C. Boffo, W. Walter BNG, Würzburg, Germany
	In this contribution we report on the spectra calculated from the field measurements performed in a liquid helium bath of 1.5 m superconducting undulator coils. The coils are foreseen for a superconducting undulator demonstrator with a period length of 15 mm planned to be installed in ANKA middle 2012 and tested at the new beamline NANO for high resolution X-ray diffraction. The spectral performance at ANKA and at low emittance sources is compared with the competing cryogenic permanent magnet technology.

MOPPP068	Beam Heat Load and Pressure in the Superconducting Undulator Installed at ANKA	electron, undulator, vacuum, simulation	717
	S. Casalbuoni, S. Gerstl, A.W. Grau, T. Holubek, D. Saez de Jauregui Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
	A superconducting undulator has been installed in the ANKA (ANgstrom source KArlsruhe) storage ring since March 2005. The beam heat load and pressure on the cold bore were analyzed in the first two years of operation, during which the undulator was operated mainly with open gap. We report here on a larger statistic of beam heat load and pressure data collected in the last years with the undulator operated at different gap positions. The effects of vacuum leaks in the storage ring on the superconducting undulator operation are also described.

MOPPP070	Characterization of Vacuum Chamber Samples for Superconducting Insertion Devices	vacuum, undulator, insertion, insertion-device	723
	D. Saez de Jauregui, T. Baumbach, S. Casalbuoni, S. Gerstl, A.W. Grau, M. Hagelstein, C. Heske, T. Holubek, B. Krause, A. Seiler, S. Stankov, L. Weinhardt Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany C.Z. Antoine, Y. Boudigou CEA/IRFU, Gif-sur-Yvette, France C. Boffo BNG, Würzburg, Germany
	One of the key components of a superconducting insertion device is the ultra-high vacuum (UHV) chamber. In order to reach the accelerator UHV specifications, it is very important to control the surface chemical content and find proper cleaning procedures. To keep the geometric and resistive wall losses small, it is essential that the top few μm of the surface exhibits low roughness and good electrical conductivity at low temperatures. A 300-μm-thick 316L stainless steel foil, galvanized with a 30-μm copper layer, is used for the next superconducting undulator developed in a collaboration between KIT and BNG. We report here on different spectroscopic analyses as well as on residual resistivity ratio RRR measurements of the copper surface after cleaning procedures and annealing at various temperatures for different periods of time.

MOPPP091	Recent Developments at the DELTA THz Beamline	laser, electron, radiation, undulator	768
	P. Ungelenk, M. Bakr, H. Huck, M. Höner, S. Khan, R. Molo, A. Nowaczyk, A. Schick, M. Zeinalzadeh DELTA, Dortmund, Germany
	Funding: Work supported by DFG, BMBF, and by the Federal State NRW. During 2011, a new dedicated THz beamline has been constructed and commissioned at DELTA, a 1.5 GeV synchrotron light source operated by the TU Dortmund University. This beamline enables extracting and detecting coherent THz pulses caused by a laser-induced density modulation of the electron bunches. Ongoing experiments aim at characterizing the THz radiation as well as investigating the evolution of the density modulation over subsequent revolutions following the initial laser-electron interaction in an undulator.

MOPPR001	Resonant Spin Depolarisation Measurements at the SPEAR3 Electron Storage Ring	electron, lattice, polarization, synchrotron	771
	K.P. Wootton, R.P. Rassool The University of Melbourne, Melbourne, Australia M.J. Boland, Y.E. Tan ASCo, Clayton, Victoria, Australia W.J. Corbett, M.H. Donald, X. Huang, R.R. Ortiz, J.A. Safranek, K. Tian SLAC, Menlo Park, California, USA
	Accurate electron beam energy measurements are valuable for precision lattice modelling of high-brightness light sources. At SPEAR3 the beam energy was measured using the resonant spin depolarisation method with striplines to resonantly excite the spin tune and a sensitive NaI scintillator beam loss monitor was used to detect resulting changes in Touschek lifetime. Using the combined apparatus an electron beam energy of 2.997251(7) GeV was measured, giving a relative uncertainty better than 3x10^-6. The measured momentum compaction factor was found to be in close agreement with the numerical model value using rectangular defocussing gradient dipoles with measured magnetic field map profiles. In this paper we outline the chosen experimental technique, with emphasis on its applicability to electron storage rings in general.

MOPPR031	BPM Data Processing Based on EPICS Soft IOC at HLS	EPICS, brilliance, injection, controls	846
	T.J. Ma, P. Lu, B.G. Sun, Y.L. Yang, Z.R. Zhou, J.Y. Zou USTC/NSRL, Hefei, Anhui, People's Republic of China
	A data analysis program has been developed and verified successfully for the new beam position monitor (BPM) system of the storage ring at Hefei Light Source (HLS). The new BPM system will be equipped with Libera Brilliance BPM processors in the upgrade project of HLS. The embedded system on Libera has completed some basic work, including data acquisition, position calculation, and EPICS IOC data output. A new record type was developed to accomplish the beam position recalculation by log-ratio method. The new position signal’s character was studied in the time and frequency domain, including distribution, RMS noise, spectrum, tune, digital filter, signal correlation, etc. Recalculation beam position showed higher sensitivity and greater linear range.

MOPPR032	Electron Beam Diagnostics based on Transverse Feedback System at Duke Storage Ring	feedback, electron, monitoring, FEL	849
	W. Xu, D.H. He USTC/NSRL, Hefei, Anhui, People's Republic of China J.Y. Li, W. Wu, 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. To combat electron beam instabilities, a field programmable gate array (FPGA) based bunch-by-bunch transverse feedback (TFB) has been developed for the Duke storage ring. While it is capable of suppressing transverse beam instabilities for multi-bunch operation, the TFB system has not been needed for typical operation of the Duke storage ring FEL. To explore the great potential of this system, we have focused on the development of TFB based beam diagnostics. A TFB based tune measurement system has been developed using two methods: the tune scan method and tune monitoring method. With the tune monitoring method, a much faster method of the two, we have studied the tune stability of the electron beam in the Duke storage ring. This tune measurement system also allows us to conduct chromaticity measurements more quickly, compared with the existing chromaticity measurement system using a network analyzer. Finally, the TFB based tune system has been used to calibrate the tune knob and chromaticity knob for the Duke storage ring.

MOPPR051	TLS Transportline BPM Upgrade	injection, booster, EPICS, diagnostics	897
	P.C. Chiu, J. Chen, Y.-S. Cheng, K.T. Hsu, K.H. Hu, C.H. Kuo, C.Y. Liao, C.Y. Wu NSRRC, Hsinchu, Taiwan
	There are seven stripline beam position monitor (BPM) installed in TLS booster to storage ring transport line. In order to provide the BPM system with better performance and functionalities, the latest generation BPM electronics Libera SinglePass had been adopted in TLS transport line for these stripline BPM. One unit had been tested in early 2011 and delivered the reliable and satisfactory results therefore extra six units had been purchased later. Currently, all of the new 7 units have replaced the past BPM electronics. The application had also been continuously developed. On the other hand, it is expected that the upgrade could enhance diagnostic functionalities for the related injection study. In this report, the injection stability and efficiency had been investigated.

MOPPR053	Improvement of BPM System for the Siam Photon Source	shielding, photon, synchrotron, controls	903
	P. Songsiriritthigul, S. Boonsuya, S. Klinkhieo, P. Klysubun, S. Krainara, P. Sudmuang, N. Suradet SLRI, Nakhon Ratchasima, Thailand J.-R. Chen, H.P. Hsueh, Y.-H. Liu NSRRC, Hsinchu, Taiwan S. Rujirawat, P. Songsiriritthigul Suranaree University of Technology, Nakhon Ratchasima, Thailand
	The Siam Photon Source (SPS) is the first synchrotron light source ever built by modifying and relocating a light source from one country to another. The SPS produced its first light in Dec 2001. The machine has been used to provide regularly synchrotron light for users since 2005. Systematic studies and investigations of the machine have properly been carried out under the supervision of the International Advisory Committee of SLRI in the last two years. This report describes the improvement of the beam position monitoring (BPM) system for the 1.2 GeV storage ring of SPS. The efficiency and reliability of the original BPM system was greatly hindered by the low quality signal cables. The replacement with the higher quality (lower loss and better interference shielding) BPM cables and the implementation of a separated cable tray for the BPM cables have significantly improved the quality of the BPM signals, allowing the possibilities for machine study and thus providing further improvement of the machine. Detailed descriptions of the work on the BPM electronic boards will be described. The measurement results before and after the improvement of the BPM system will also be presented.

MOPPR054	Beam Size Measurement at Siam Photon Source Storage Ring	synchrotron, monitoring, radiation, photon	906
	P. Sudmuang, N. Deethae, P. Klysubun, S. Krainara, T. Poolampong, K. Sitisart, N. Suradet SLRI, Nakhon Ratchasima, Thailand
	Synchrotron radiation interferometer and direct imaging setups have been installed and subsequently utilized to investigate transverse beam profile at the Siam Photon Source (SPS). Details of the optical setup as well as the beam sizes determined from the measurement will be presented. Comparison between the measured and theoretical values as established by linear optics calibration will be made and discussed. In order to demonstrate the beam profiling capability of the interferometer and direct imaging systems, measurements with different operating parameters have been carried out and the results will be presented as well.

TUOAB01	Timing and Synchronization for the APS Short Pulse X-ray Project	laser, cavity, feedback, LLRF	1077
	F. Lenkszus, N.D. Arnold, T.G. Berenc, G. Decker, E.M. Dufresne, R.I. Farnsworth, Y.L. Li, R.M. Lill, H. Ma ANL, Argonne, USA J.M. Byrd, L.R. Doolittle, G. Huang, R.B. Wilcox LBNL, Berkeley, California, USA
	Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. The Short-Pulse X-ray (SPX) project, which is part of the APS upgrade, will provide intense, tunable, high-repetition-rate picosecond x-ray pulses through the use of deflecting cavities operating at the 8th harmonic of the storage-ring rf. Achieving this picosecond capability while minimizing the impact to other beamlines outside the SPX zone imposes demanding timing and synchronization requirements. For example, the mismatch between the upstream and downstream deflecting cavities' rf field phase is specified to be less than 0.077 degrees root mean squared (rms) at 2815 MHz (~77 femtoseconds). Another stringent requirement is to synchronize beamline pump-probe lasers to the SPX x-ray pulse to 400 femtoseconds rms. To achieve these requirements we have entered into a collaboration with the Beam Technology group at LBNL. They have developed and demonstrated a system for distributing stable rf signals over optical fiber capable of achieving less than 20 femtoseconds rms drift and jitter over 2.2 km over 60 hours. This paper defines the overall timing/synchronization requirements for the SPX and describes the plan to achieve them. R. Wilcox et al. Opt. Let. 34(20), Oct 15, 2009
	Slides TUOAB01 [2.515 MB]

TUOBB02	Commissioning of the PLS-II	insertion, insertion-device, power-supply, lattice	1089
	S. Shin, J.Y. Choi, T. Ha, J.Y. Huang, I. Hwang, W.H. Hwang, Y.D. Joo, C. Kim, D.T. Kim, D.E. Kim, J.M. Kim, M. Kim, S.H. Kim, S.-C. Kim, S.J. Kwon, B.-J. Lee, E.H. Lee, H.-S. Lee, H.M. Lee, J.W. Lee, S.H. Nam, E.S. Park, I.S. Park, S.S. Park, S.J. Park, Y.G. Son, J.C. Yoon PAL, Pohang, Kyungbuk, Republic of Korea J-Y. Kim, B.H. Oh KAERI, Daejon, Republic of Korea J. Lee POSTECH, Pohang, Kyungbuk, Republic of Korea
	The Pohang Light Source (PLS) has operated for 14 years successfully. To meet the request of the increasing user community, the PLS-II that is the upgrade project of PLS has been completed. Main goals of the PLS-II are to increase beam energy to 3 GeV, to increase number of insertion devices by the factor of two (20 IDs), to increase beam current to 400 mA and to reduce beam emittance below 10 nm with existing PLS tunnel and injection system. The PLS-II had been commissioned over the six months. During commissioning, we achieved 14 insertion devices operation and top-up operation with 100 mA beam current and 5.8 nm beam emittance. In this presentation, we report the experimental results from the PLS-II commissioning.
	Slides TUOBB02 [3.484 MB]

TUEPPB008	Status Report on the Iranian Light Source Facility Project	booster, cavity, synchrotron, dipole	1131
	J. Rahighi, H. Ajam, R. Aslani, S. Fatehi, H. Ghasem, M.R. Khabazi, R. Safian, E. Salimi, A. Shahveh IPM, Tehran, Iran E. Ahmadi, M. Jafarzadeh, H.B. Jalali, M. Moradi, S. Pirani, M. Rahimi, A. Sadeghipanah, F. Saeidi, Kh.S. Sarhadi, A. Shahverdi ILSF, Tehran, Iran D. Einfeld CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	The Iranian Light Source Facility Project (ILSF) is a 3rd generation light source with an energy of 3 GeV,a full energy injector and a 100 MeV linac as preinjector. For storage ring, booster synchrotron and linac including the transfer lines, a draft design has been completed and will be presented. The storage ring has an emittance of 3.3 nm-rad, a circumference of 297.6 meters with an overall of 32 straight sections of different lengths. The booster synchrotron has a circumference of 197 meters and emittance of 35nm-rad. For the booster synchrotron a new lattice is proposed. The linac is a conventional 150 MeV accelerator. The different accelerator components, magnets, girders, power supplies, vacuum systems etc. are in the design phase. State of the art design for different components is employed through international collaboration.

TUPPC016	Progress of Emittance Coupling Correction at the SPring-8 Storage Ring	coupling, resonance, betatron, survey	1191
	M. Takao, M. Masaki, Y. Shimosaki, K. Soutome, S. Takano, C. Zhang JASRI/SPring-8, Hyogo-ken, Japan
	The vertical beam spread, or the emittance coupling, is one of the most important parameters for the high brilliance light source storage ring. By the precise alignment of the magnets and the proper COD correction, at the commissioning phase of the SPring-8 storage ring we succeeded in achieving the very small coupling ~0.2 % without correction. However, the coupling had grown large with the years, so recently we have corrected it and recovered the initial performance. The scheme of the coupling correction at the SPring-8 storage ring is the global one, which is based on the perturbation theory with single resonance approximation. In the beginning of the correction the coupling was corrected by means of minimizing the vertical beam size. Then the performance of the coupling correction has been further improved by changing the scheme to minimizing the betatron coupling mode in the vertical oscillation of the horizontally kicked beam. This result implies that the higher order coupling contributes to the emittance coupling, which can be corrected by the higher skew multi-pole magnet. The present status of the coupling correction at the SPring-8 storage ring will be reported.

TUPPC025	Solaris Storage Ring Lattice Optimization with Strong Insertion Devices	lattice, optics, undulator, insertion	1218
	A.I. Wawrzyniak, C.J. Bocchetta Solaris, Kraków, Poland M. Eriksson, S.C. Leemann MAX-lab, Lund, Sweden
	Funding: Work supported by the European Regional Development Fund within the frame of the Innovative Economy Operational Program: POIG.02.01.00-12-213/09 The Solaris synchrotron light facility under construction in Kraków will be a replica of the 1.5 GeV storage ring of MAX IV. This compact 3rd generation light source has been designed to have an emittance of 6 nmrad and operate with 500 mA stored current for VUV and soft X-Rays production. The lattice design consists of 12 Double Bend Achromats (DBA) with each DBA cell integrated into one solid iron block. Twelve 3.5 m long straight sections are available of which 10 will be equipped in various insertion devices. These devices will differ from those adopted by MAX IV. For X-ray production one or more superconducting wigglers will be used, while APPLE II type undulators will be used for variable polarised light production. The linear and nonlinear lattice dynamics have been studied with these perturbing insertion devices included in the ring and results are presented in this paper.

TUPPC047	New Storage Ring Lattice for the Duke FEL Wiggler Switchyard System	wiggler, lattice, FEL, quadrupole	1272
	H. Hao, J.Y. Li, 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. The Duke storage ring is a dedicated drive for the OK-4 FEL and OK-5 FEL, and for the state-of-the-art Compton gamma-ray source, High Intensity Gamma-Ray Source (HIGS). To produce FEL lasing below 190 nm and gamma-ray beams above 100 MeV, the FEL system needs to be upgraded by adding two helical OK-5 wigglers to increase the FEL gain with four OK5 wigglers for the VUV operation. To simultaneously preserve the linear polarization capability of the gamma-ray beam produced by the planar OK-4 FEL, a wiggler switchyard system is under development which will enable the switch between two planar OK-4 wigglers and two helical OK-5 wigglers in the middle of the FEL straight. In this work, we present the new magnetic lattice designed for the operation of the wiggler switchyard system. This new lattice is developed with great flexibility for the operation with different numbers of FEL wigglers, variable betatron tunes, and adjustable electron beam sizes at the collision point for the HIGS. In addition, the new lattice is developed for the operation in a wide range of energies, from 280 MeV to 1.2 GeV, with proper nonlinear dynamics compensations in order to realize a large dynamic aperture.

TUPPC070	Alternating Spin Aberration Electrostatic Lattice for EDM Ring	lattice, simulation, quadrupole, proton	1332
	Y. Senichev, R. Maier, D. Zyuzin FZJ, Jülich, Germany M. Berz MSU, East Lansing, Michigan, USA
	The idea of the electric dipole moment search using the storage ring (SrEDM) with polarized beam is realized under condition of the long-time spin coherency of all particles, the time during which the RMS spread of the spin orientation of all particles in the bunch reaches one radian. Following the requirements of the planned EDM experiment, the SCT should be more than 1000 seconds. During this time each particle performs about 10⁹ turns in the storage ring moving on different trajectories through the optics elements. At such conditions the spin-rotation aberrations associated with various types of space and time dependent nonlinearities start to play a crucial role. In this paper we consider a new method based on the alternating spin drift, causing it to rotate alternately, thereby limiting the growth of aberrations at one order of magnitude lower. As a result, using this method we can achieve the SCT of the order of 5000-6000 seconds. The difficulties of these studies are still in the fact that the aberrations growth observed in the scale of a 10⁹ turns. For the study we use an analytical method in composition with a numerical simulation by COSY Infinity.

TUPPC074	Study of Resonance Driving Term in Electron Storage Rings	damping, radiation, resonance, electron	1344
	G. Liu, W. Li, L. Wang USTC/NSRL, Hefei, Anhui, People's Republic of China
	The resonance driving term (RDT) is useful to analyze and optimize the nonlinear performance of the storage ring. In addition to analytical calculation of RDT, experimental measurement of RDT has been made in some proton storage rings based on turn-by-turn BPM data. For electron storage rings, the analysis is more complicated due to decoherence effects and strong radiation damping. The relation between spectral decomposition of BPM data and RDT is derived and validated using beam numerical tracking data in this paper.

TUPPD005	Design Concept for Nu-STORM: an Initial “Very Low-Energy Neutrino Factory”	injection, target, proton, factory	1413
	D.V. Neuffer, A.D. Bross, S. Geer, A. Liu, M. Popovic Fermilab, Batavia, USA C.M. Ankenbrandt, T.J. Roberts Muons, Inc, Batavia, USA
	Funding: US DOE under contract DE-AC02-07CH11359 We present a design concept for a Nu-source from a STORage ring for Muons - NuSTORM. In this initial design a high-intensity proton beam produces ~5 GeV pions that provide muons that are captured using “stochastic injection” within a ~3.6 GeV racetrack storage ring. In “stochastic injection”, the ~53 GeV pion beam is transported from the target into the storage ring, dispersion-matched into a long straight section. (Circulating and injection orbits are separated by momentum.) Decays within that straight section provide muons that are within the ~2 GeV/c ring momentum acceptance and are stored for the muon lifetime of ~1000 turns. Muon (and pion) decays in the long straight sections provide neutrino beams that can be used for precision measurements of neutrino interactions, and neutrino oscillations or disappearance at L/E=~1 m/MeV. The facility is described and variations are discussed.

TUPPD043	Resonant Reaction with a Superintense Circulating Beam	target, proton, electron, resonance	1497
	V.G. Dudnikov, C.M. Ankenbrandt Muons, Inc, Batavia, USA
	A system for efficient generation of resonance reaction in the interaction of the circulating ion beam with a thin internal target is considered. Features of this system are high intense space charge compensated circulating ion beam with an intensity greater then a space charge limit in a near integrable nonlinear focusing system. Ionization energy loss is compensated by inductive electric field. Multiple scattering and energy straggling are compensated by electron cooling with a tabular electron beam. In this method it is possible to compensate an energy loss of circulating particles after crossing the target and have a crossing of resonant energy in every passing of target. For sharp resonance reactions and monoenergetic beams a thin target method can increase greatly the energy efficiency.

TUPPP007	Modifications to the Machine Optics of BESSY II Necessitated by the EMIL Project	undulator, optics, cryogenics, dipole	1614
	P.O. Schmid, J. Bahrdt, T. Birke, R. Follath, P. Kuske, D. Simmering, G. Wüstefeld HZB, Berlin, Germany
	The Helmholtz Zentrum Berlin and the Max Planck Society are going to build a new dedicated X-ray beam line at the synchrotron source light source BESSY II which will be used for analyzing materials for renewable energy generation. The new large scale project has been dubbed EMIL. In this document we present the modifications to the machine optics and to what extent these changes affect the performance of BESSY II.

TUPPP010	Spectral and Temporal Observations of CSR at ANKA	radiation, synchrotron, optics, synchrotron-radiation	1623
	V. Judin, N. Hiller, A. Hofmann, E. Huttel, B. Kehrer, M. Klein, S. Marsching, C.A.J. Meuter, A.-S. Müller, M. Schuh, M. Schwarz, N.J. Smale, M. Streichert KIT, Karlsruhe, Germany M.J. Nasse Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
	Funding: This work has been supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320. ANKA is a synchrotron light source situated at the Karlsruhe Institute of Technology. Using dedicated low-α-optics at ANKA we can reduce the bunch length and generate Coherent Synchrotron Radiation (CSR). Studies of the coherent emission in the time domain allow us to gain an insight into the longitudinal bunch dynamics. These as well as the systematic investigations of the THz spectrum range can be used for benchmarking of theoretical predictions. In this paper we report about the recent progress in CSR observation using fast THz detectors and a Martin-Puplett spectrometer at the ANKA storage ring.

TUPPP011	Simulations of Fringe Fields and Multipoles for the ANKA Storage Ring Bending Magnets	multipole, simulation, optics, sextupole	1626
	M. Streichert, M.J. Nasse Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany V. Afonso Rodriguez, A. Bernhard, N. Hiller, E. Huttel, V. Judin, B. Kehrer, M. Klein, S. Marsching, C.A.J. Meuter, A.-S. Müller, M. Schwarz, N.J. Smale KIT, Karlsruhe, Germany
	Funding: This work has been supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320. ANKA is the synchrotron light source of the Karlsruhe Institute of Technology (KIT). With a maximum particle energy of 2.5 GeV, the storage ring lattice consists of 16 bending magnets with a nominal magnetic flux density of 1.5 T. For the beam dynamics simulations the consideration of the fringe fields and multipoles is essential. A reference measurement of the longitudinal magnetic flux density profile of a bending magnet exists for a current of 650 A, corresponding to a particle energy of 2.46 GeV. For lower beam energies where the magnets are no longer close to saturation, however, the exact density profiles may vary significantly. In order to derive fringe fields and multipole components for different beam energies, simulations of the magnetic flux density for different beam energies were conducted using a finite element method (FEM). We present the results of the simulations and demonstrate the improvements of the beam dynamics simulations in AT (Accelerator Toolbox).

TUPPP015	Status and Recent Progress of SPring-8	coupling, emittance, lattice, optics	1638
	H. Ohkuma JASRI/SPring-8, Hyogo-ken, Japan
	The SPring-8 is an 8 GeV synchrotron radiation facility that has been in operation since 1997. The SPring-8 has been operated well and total user time has reached more than 53,700 hours, 75% of the total operation time. The average user time per year is about 4,000 hours. The average availability is about 98% in the past 15 years. The operational status and recent progress overview of SPring-8 is presented: the local lattice modification of 30-m long straight section for installing small gap (min. gap is 5.2 mm) in-vacuum undulators, the emittance coupling correction for the vertical beam size reduction, the test operation of low energy operation for the energy saving, and the study of lower emittance optics for the present SPring-8 storage ring. An outline of a future upgrade with a full-scale major lattice modification is also presented. We also present a little about recent progress of SPring-8 injecting accelerators.

TUPPP018	Design and Commissioning of the Very Low Emittance Optics in the SSRF Storage Ring	emittance, optics, injection, lattice	1647
	S.Q. Tian, J. Chen, B.C. Jiang, Y.B. Leng, H.H. Li, L.Y. Yu, M.Z. Zhang, W.Z. Zhang, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	In synchrotron radiation light sources, there are continuous efforts to lower the storage ring emittance and thus increase its photon beam brightness. The lowest effective emittance of SSRF is found by a systematic method. Results of design and commissioning of this kind of optics are presented, of which the beam emittance is smaller than the nominal one by 1 nm.rad. The measured beam parameters agree well with the design ones.

TUPPP019	Overview of the Solaris Facility	linac, klystron, dipole, vacuum	1650
	C.J. Bocchetta, M. Bartosik, P.P. Goryl, K. Królas, M. Młynarczyk, W. Soroka, M.J. Stankiewicz, P.S. Tracz, Ł. Walczak, A.I. Wawrzyniak, K. Wawrzyniak, J.J. Wiechecki, M. Zając, L. Zytniak Solaris, Kraków, Poland R. Nietubyć The Andrzej Soltan Institute for Nuclear Studies, Centre Świerk, Świerk/Otwock, Poland
	Funding: Work supported by the European Regional Development Fund within the frame of the Innovative Economy Operational Program: POIG.02.01.00-12-213/09 The Polish synchrotron light source Solaris is under construction in Kraków. The project is based on the MAX IV light source being built in Lund, Sweden. The 1.5 GeV storage ring for Solaris and part of the injector complex are identical to that of MAX IV, although both are housed in buildings that differ from those of MAX IV. Ground breaking on the green field site at the Jagiellonian University campus occurred at the start of 2012. A detail description of the facility infrastructure, services and construction choices is given together with the latest project developments for main accelerator systems.

TUPPP022	Beam Optics Measurements during ALBA Commissioning	quadrupole, lattice, optics, emittance	1656
	M. Muñoz, G. Benedetti, J. Campmany, D. Einfeld, Z. Martí CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	The synchrotron light source ALBA is in the final stage of the Storage Ring commissioning, with the beamline commissioning well under way. This paper reviews the results of the modeling of the lattice and the agreement with the LOCO measurement of the machine; the performance of the beta beating correction (critical in the ALBA case due to the large gradient in the bending magnet and the low number of quadrupole families), including effect of insertion devices; the lifetime measurement; tune scans; tune shift with horizontal amplitude; and the general agreement of the machine to the model using during the design. A brief summary of the modeling of the injector chain is included.

TUPPP023	Operation Status of ALBA Synchrotron Light Source	feedback, vacuum, emittance, kicker	1659
	M. Pont CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain
	ALBA is a 3.0 GeV third generation synchrotron light source which has been commissioned during 2011. From October 2011 up to 7 beamlines are delivering beam for beamline commissioning, 6 from insertion devices and 1 from a bending magnet. Since April 2012 the facility is open to external users. Beam current has been continuously increased and the present stored beam current for users is 200 mA in a multi-bunch filling pattern. Orbit stability is kept at ±1 micron with a slow orbit feedback. The paper will review the operation and performance status of the different subsystems and review also the main objectives for 2012: target current of 400 mA, delivery of 3000 hours of beam to beamlines, testing of a fast orbit feedback system as well as preparations for top-up operation.

TUPPP024	Recent Progress on the MAX IV 1.5 GeV Storage Ring Lattice and Optics	lattice, dipole, vacuum, sextupole	1662
	S.C. Leemann MAX-lab, Lund, Sweden
	Construction of the MAX IV facility started in 2010 and commissioning is expected to begin in 2014. Once completed, the facility will include two storage rings for the production of synchrotron radiation. The 3 GeV ring will house insertion devices for the production of x-rays, while the 1.5 GeV ring will serve UV and IR users. Recently, the lattice and optics of the 1.5 GeV storage ring have been modified as a result of detailed magnet and vacuum system design. This paper discusses the lattice and optics changes as well as their effects.

TUPPP025	Resurrection of RESOLVE at NSRRC Prepared for the First Turn Beam Steering of the TPS Commissioning	injection, controls, quadrupole, kicker	1665
	H.-P. Chang, H.H. Chen, P.C. Chiu, P.J. Chou, K.T. Hsu, S.J. Huang, Y.-C. Liu, F.H. Tseng NSRRC, Hsinchu, Taiwan
	MATLAB based high level application software prepared for the 3GeV Taiwan Photon Source has been built and tested on the 1.5GeV Taiwan Light Source continuously. The RESOLVE program is surveyed and resurrected at NSRRC to support and help the first turn beam steering in the coming commissioning of the TPS accelerator complex. Due to the RESOLVE’s history, it contributed a lot in the past commissioning of SLC at SLAC National Accelerator Laboratory, we believe it may give help although most of the first turn beam steering of current light source machines may pass smoothly with well machine construction. In order to make the revised RESOLVE working, not only the compiling problem but also some memory bugs have been fixed, the updated RESOLVE now can be run on PC/Linux and Mac/OSX computer systems. We are trying to apply and test it on the TLS SR with the turn-by-turn digital BPM system. Some exercises of the error finding in beam steering of the off-axis injection beam are performed for presentation.

TUPPP028	A Study of Girder Alignment with Survey Measurements In the Diamond Storage Ring	survey, closed-orbit, sextupole, insertion	1674
	M. Apollonio, R. Bartolini, R.T. Fielder, W.J. Hoffman, J. Kay, I.P.S. Martin, B. Singh Diamond, Oxfordshire, United Kingdom
	Using a model of the Diamond storage ring which includes displacements and rotations of the 74 magnet girders an attempt has been made to correlate survey data with the corrector magnet (CM) strengths required for a zero orbit. We then use the model to deduce the most effective girder movements that will bring about a reduction in corrector strength. We describe the results of these studies, and suggest a test with a deliberately displaced girder and the effect on corrector strengths, aimed at enhancing our understanding of the system

TUPPP032	Use of Multi-objective Methods for Choosing Undulators for Storage Rings	brightness, photon, undulator, target	1680
	M. Borland ANL, Argonne, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Users of storage ring light sources generally rely on undulators to provide the highest brightness. Choice of the optimal undulator period is complicated by the fact that users do not operate at a single photon energy or place equal weight on operation at all photon energies of interest. In addition, some users may be best served by a double- or triple-period revolver device. In this paper, we present a method of narrowing the choice of undulator periods based on multi-objective techniques. Applications are shown in the context of the Advanced Photon Source Upgrade.

TUPPP033	Exploration of a Tevatron-sized Ultimate Storage Ring	emittance, brightness, damping, sextupole	1683
	M. Borland ANL, Argonne, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. With the Tevatron now shut down and slated for decommissioning, it is only natural to think about other possible uses for the 6.3 km tunnel. Given that the brightness of electron storage rings naively scales as radius cubed, one exciting possibility is to build a so-called ultimate storage ring light source. This paper describes a somewhat speculative exploration of this idea, showing the potential for a storage ring x-ray source of unprecedented brightness.

TUPPP042	Passive Landau Cavity Effects in the NSLS-II Storage Ring	cavity, simulation, impedance, wakefield	1701
	G. Bassi, A. Blednykh, S. Krinsky BNL, Upton, Long Island, New York, USA
	Funding: Work supported by DOE contract No: DE-AC02-98CH10886. In new 3rd generation synchrotron light sources with small transverse emittance, higher harmonic cavities (Landau cavities) are installed for bunch lengthening to increase the Touschek lifetime, and to provide Landau damping for beam stability. In this contribution we study the effects of passive Landau cavities in the NSLS-II storage ring for arbitrary fill-patterns with the OASIS tracking code.

TUPPR057	Intrabeam Scattering Studies at the Swiss Light Source	emittance, damping, scattering, monitoring	1951
	F. Antoniou, Y. Papaphilippou CERN, Geneva, Switzerland M. Aiba, M. Böge, N. Milas, A. Streun Paul Scherrer Institut, Villigen, Switzerland T. Demma INFN/LNF, Frascati (Roma), Italy
	The target parameters of modern ultra-low emittance rings are entering into a regime where intra-beam scattering (IBS) becomes important and, in the case of linear collider damping rings, even a limitation for the delivered emittances. The Swiss Light Source (SLS) storage ring, as it has achieved a vertical geometrical emittance of around 2 pm at 2.4 GeV, and it has the ability to run at even lower energies, and the availability of emittance monitoring diagnostics, is an ideal test bed for IBS studies. Simulations using the classical IBS theories and tracking codes are undertaken in order to explore the possibilities and limitations for IBS measurements at the SLS. In this respect, comparison between the theories and codes is first discussed. The dependence of the output emittances, taking into account the effect of IBS, with respect to energy, bunch charge and zero current vertical and longitudinal emittance is also studied, in order to define the regimes where the IBS effect can be significant. First measurement results from the SLS running at lower energies are finally presented.

WEOAA01	Injected Beam Imaging at SPEAR 3 with a Digital Optic Mask	injection, synchrotron, target, quadrupole	2116
	H.D. Zhang, R.B. Fiorito, A.G. Shkvarunets UMD, College Park, Maryland, USA W.J. Corbett, A.S. Fisher, K. Tian SLAC, Menlo Park, California, USA
	Funding: *This work is partially funded by the Office of Naval Research and the DOD Joint Technology Office. At SPEAR3, the light source operates in top-up injection mode with 273nC charge circulating in the storage ring (350mA). Each individual injection pulse contains only 40pC, or a contrast ration of 1:6800. In order to monitor injected beam dynamics during User operations, it is desirable to optically image the injected charge distribution on a turn-by-turn basis in the presence of the bright stored beam. The measurement is made by re-imaging visible synchrotron radiation onto a 1024x768 pixel Digital-Micro-Array mirror device (DMD) which is used to 'mask' light from the central stored beam while observing the weak injected beam signal on an intensified, fast-gated CCD camera. Complex beam dynamics are observed after only a few 10's of turns around the synchrotron. In this paper we report on the DMD optical configuration, masking considerations, measurement timing and initial tests imaging the injected beam in the presence of stored beam.
	Slides WEOAA01 [1.874 MB]

WEPPD010	Re-commissioning of the ESRF Storage Ring Vacuum System	vacuum, synchrotron, insertion, insertion-device	2516
	M. Hahn, I. Parat ESRF, Grenoble, France
	A long shutdown of the accelerators to allow the construction of new buildings marked the phase one of the ESRF upgrade program. A number of vacuum sectors has been modified during this time for repair and maintenance but mainly to increase the brilliance of the synchrotron radiation beams by installing longer insertion device (ID) vessels with non-evaporable getter (NEG) coating and a new In Vacuum Undulator. The paper gives an overview of the modified machine and reports experience with its re-conditioning.

WEPPD022	Design of the Water-Cooling System for the Vacuum System of the TPS Storage Ring	vacuum, synchrotron, photon, controls	2546
	Y.C. Yang, C.K. Chan, J.-R. Chen, C.M. Cheng, G.-Y. Hsiung NSRRC, Hsinchu, Taiwan
	Taiwan Photon Source (TPS) was under construction since 2009. TPS vacuum system was designed in 10^-10 torr level and gas load from synchrotron light was almost confined in bending chambers. A water cooling system was designed to protect vacuum equipment including vacuum chambers and absorbers to avoid melting down by synchrotron light. There are 3 cooling loops for aluminum chambers and 4 loops for cooper absorbers in one unit cell. One prototype for unit cell, including arrangement of control terminal, monitor of flow rate and temperature, and vibration from cooling system will be tested.

WEPPD026	Design and Fabrication of NSLS-II Storage Ring Vacuum Chambers and Components	vacuum, photon, multipole, impedance	2558
	H.-C. Hseuh, A.T. Anderson, L. Doom, M.J. Ferreira, C. Hetzel, C. Longo, V. Ravindranath, K. Roy, S.K. Sharma, J.L. Tuozzolo, K. Wilson BNL, Upton, Long Island, New York, USA
	Funding: Work performed under the auspices of U.S. Department of Energy, under contract DE-AC02-98CH10886 The National Synchrotron Light Source II, a 3-GeV, 792-meter circumference, synchrotron radiation facility with ultra-high-flux and brightness, is under construction at Brookhaven National Laboratory. The storage ring vacuum chambers are mainly made of extruded aluminium but with a few made of stainless steel and inconel. The synchrotron radiation from bending magnets is intercepted at discrete photon absorbers made of GlidCop. NEG strips in the ante-chamber provide the distributed pumping, while lumped ion pumps and titanium sublimation pumps at photon absorbers remove the desorbed gas. The complex vacuum system is being assembled and integrated in-house. This paper describes the design and fabrication of both standard and special vacuum chambers, the low impedance RF shielded bellows and the photon absorbers. The vacuum system is now moving into the conditioning, installation and testing phase. Details and experience from the large scale production, testing and lesson learned will also be presented.

WEPPD039	Status of the Utility System Construction for the 3 GeV TPS Storage Ring	status, booster, controls, power-supply	2597
	J.-C. Chang, W.S. Chan, J.-R. Chen, Y.F. Chiu, Y.-C. Chung, K.C. Kuo, Y.-C. Lin, C.Y. Liu, I. 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 will be completed in the end of 2011. The whole construction of the utility system is scheduled to be completed in the end of 2012. 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.

WEPPD045	An Application of Multi-stage Adjustable Shock Absorbers for the Girders of Storage Ring in Taiwan Photon Source	damping, acceleration, controls, photon	2615
	C.-S. Lin, J.-R. Chen, M.L. Chen, H.C. Ho, K.H. Hsu, D.-G. Huang, C.K. Kuan, W.Y. Lai, C.J. Lin, H.M. Luo, S.Y. Perng, P.L. Sung, Y.L. Tsai, T.C. Tseng, H.S. Wang, M.H. Wu NSRRC, Hsinchu, Taiwan D.-Y. Chiang NCKU, Tainan city, Taiwan
	Beam stability is a major concern for the operation of the Taiwan Photon Source (TPS). One of the many factors to instability of electron beam is mechanical vibration of the accelerator components. The TPS uses steel girders to support the magnets and vacuum chambers in the storage ring. Three pedestal and six mover assemblies support the girders. Multi-stage adjustable shock absorbers are designed for passive vibration damping, and presently installed between the girders and the pedestals. Through adjusting the amount of hydraulic fluid which bypasses the damping passage between two hydraulic chambers, the desired damping coefficient of the damping absorbers can be achieved. Experimental results of modal testing presented in this paper show that the multi-stage adjustable damping absorbers under the assembly of the girders reduced the level of girder vibration.

WEPPD046	Design of Machine Protection System for the Taiwan Photon Source	EPICS, controls, vacuum, status	2618
	C.Y. Liao, J. Chen, Y.-S. Cheng, K.T. Hsu, K.H. Hu, C.H. Kuo, D. Lee, C.Y. Wu NSRRC, Hsinchu, Taiwan
	The Taiwan Photon Source (TPS) is being constructed at the campus of the NSRRC (National Synchrotron Radiation Research Center). In order to prevent damage to accelerator components induced by various events, design of the global machine protection system (MPS) is on-going. The MPS collect interlock and beam dump request from various system, perform decision, transmit dump beam request to RF system. The PLC based system will be used as a slow MPS which can delivery less than 8 msec reaction time. The fast MPS will dependent on event based timing system to deliver response time less than 5 μsec. Trigger signal for post-mortem will also be distributed by the fast MPS. To ensure alive of the system, several self-diagnostics mechanisms include heartbeat and transient capture will be implemented. The MPS architecture, plans and implementation were presented in this report.

WEPPP018	A New Beam Injection Scheme for a Compact Low-energy Storage Ring	injection, kicker, damping, acceleration	2761
	Y. Honda KEK, Ibaraki, Japan
	A very compact storage ring at low energy has an unique application such as Compton X-ray source. Scheme for efficient injection is an issue for such a compact storage ring. Utilizing a phase-shift in the non-relativistic energy region, a new idea for accumulating the incoming bunch on an already circulating bunch without any kicker or orbit bump has been presented. Its applicable parameter range will be presented.

WEPPP057	Orbit Correction Studies using Neural Networks	controls, simulation, target, synchrotron	2837
	E. Meier, G. LeBlanc, Y.E. Tan ASCo, Clayton, Victoria, Australia
	This paper reports the use of Neural Networks for orbit correction at the Australian Synchrotron Storage Ring. The proposed system uses two Neural Networks in an actor-critic scheme to model a long term cost function and compute appropriate corrections. The system is entirely based on the history of the beam position and the actuators, the corrector magnets, in the storage ring. This makes the system auto-tuneable, which has the advantage of avoiding the use of a response matrix. As a generic and robust orbit correction program it can be used during commissioning and in slow orbit feedback. In this study, we present positive initial results of the simulations of the storage ring in Matlab. We will also discuss the possibility of reconstructing the response matrix from the information stored in the neural network for offline orbit response matrix analysis.

WEPPP062	Characterization and Stabilization of Multi-Bunch Instabilities at the ANKA Storage Ring	feedback, kicker, injection, controls	2849
	E. Huttel FZK, Karlsruhe, Germany N. Hiller, E. Huttel, V. Judin, B. Kehrer, S. Marsching, A.-S. Müller, N.J. Smale KIT, Karlsruhe, Germany
	ANKA is a 2.5 GeV storage ring for synchrotron radiation. Up to 200 mA are accumulated at 0.5 GeV and then ramped to 2.5 GeV. In the past storage ring operation suffered from vertical multi-bunch instabilities. These could partially be cured by increased chromaticity, a large gap in the filling structure and by keeping the beam longitudinally unstable. A vertical digital bunch-by-bunch system from ITECH has been installed that allows an operation of the storage ring without exciting the longitudinal modes. In addition, the system allows analyzing multi-bunch instabilities both transverse and longitudinal and their dependence from cavity temperature, filling structure and chromaticity. This paper reports on our experience operating this system and presents an investigation of multi-bunch modes in the ANKA storage ring.

WEPPP064	Design and Simulation of the Stripline Transverse Quadrupole Kicker for HLS II	quadrupole, kicker, impedance, dipole	2852
	F.F. Wu, W.B. Li, P. Lu, T.J. Ma, B.G. Sun, Y.Y. Xiao, H. Xu, Y.L. Yang, Z.R. Zhou USTC/NSRL, Hefei, Anhui, People's Republic of China
	In order to investigate the possibility of excite a transverse quadrupole mode oscillation of the electron bunch in the HLS II storage ring, we design a stripline transverse quadrupole kicker. The characteristic impedance of some modes(dipole modes, sum mode, quadrupole mode) of the optimised stripline kicker must match 50Ω characteristic impedance of the external transmission lines so as to reduce the reflected power. We use nonlinear least square method to optimise the kicker and compare characteristic impedances of calculation using 2D Possion code and fitted function of several variables, then we get optimised size with integrated use of Possion code and fitted function of several variables. Using the 2D Poisson code, we simulate the electric field distribution of dipole modes when the horizontal or the vertical electrodes are at opposite unit potentials, and the electric field distribution of quadrupole mode using quadrupole kick. We verified that the designed stripline kicker can excite a transverse quadrupole mode oscillation of the electron bunch.

WEPPP065	Status of the SSRF Fast Orbit Feedback System	feedback, controls, electron, insertion	2855
	B.C. Jiang, J. Hou, C.X. Yin, Z.T. Zhao SINAP, Shanghai, People's Republic of China
	The fast orbit feedback system with bandwidth up to 100Hz is under commissioning at SSRF. The main purposes of the system are to suppress the short term orbit stability under sub-micron level and to compensate the orbit distortions caused by changing gaps of the insertion devices. The layout of the system is described and the preliminary commissioning results are given out in this paper.

WEPPP067	Commissioning Results of Slow Orbit Feedback using PID Controller Method for the Siam Photon Source	feedback, controls, photon, LabView	2861
	S. Klinkhieo, S. Boonsuya, P. Klysubun, S. Krainara, P. Songsiriritthigul, P. Sudmuang, N. Suradet SLRI, Nakhon Ratchasima, Thailand S. Rujirawat Suranaree University of Technology, Nakhon Ratchasima, Thailand
	A slow orbit feedback (SOFB) system has been developed to improve the orbit stability for the storage ring of the Siam Photon Source (SPS). The SOFB uses a PID controller method utilizing LabVIEW channel to access 20 BPMs and 28 correctors of the storage ring. The first phase implementation of the feedback loops based on this method was operated at 0.05Hz of sampling frequency, which reduce the fluctuation of both horizontal and vertical positions of the orbit from ~200 microns down to ~30 microns. The commissioning results indicate that further work and hardware upgrade are required. A higher sampling frequency at least 30Hz is strongly required for PID controller implementation. Upgrading of the existing 12-bit resolution corrector power supplies is also necessary. The basic principle of PID algorithms, hardware, software and commissioning results of the current SOBF system, as well as a future development plan, will be presented.

WEPPP069	Performance Enhancements for the Transverse Feedback System at the Advanced Photon Source	feedback, EPICS, photon, controls	2867
	N.P. Di Monte, R.I. Farnsworth, A.J. Scaminaci ANL, Argonne, USA
	With the success of the transverse feedback system at the Advanced Photon Source (APS), an upgrade to this system is being developed. The current system is operating at a third of the storage ring bunch capacity, or 324 of the available 1296 bunches. This upgrade will allow the sampling of all 1296 bunches and make corrections for all selected bunches in a single storage ring turn. To facilitate this upgrade, a new analog I/O board capable of 352-MHz operation is being developed along with a P0 bunch cleaning circuit. The clock cleaning circuit is also needed for the high speed analog output circuit, which is transmitted about 200 m to a separate DAC unit in real time. This remote DAC will have its transceiver data rate triple from 2.3 Gb to about 7 Gb on a fiber optic link. This paper will discuss some of the challenges in reducing the clock jitter from the system P0 bunch clock along with the necessary FPGA hardware upgrades and algorithm changes, all of which are required for the success of this upgrade.

WEPPP070	Simulation of the APS Storage Ring Orbit Real-Time Feedback System Upgrade Using MATLAB	feedback, simulation, controls, dipole	2870
	S. Xu, G. Decker, R.I. Farnsworth, F. Lenkszus, H. Shang, X. Sun ANL, Argonne, USA
	Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. The Advanced Photon Source (APS) storage ring orbit real-time feedback (RTFB) system plays an important role in stabilizing the orbit of the stored beam. An upgrade is planned that will improve beam stability by increasing the correction bandwidth to 200 Hz or higher. To achieve this, the number of available steering correctors and beam position monitors (BPMs) will be increased, and the sample rate will be increased by an order of magnitude. An additional benefit will be the replacement of aging components. Simulations have been performed to quantify the effects of different system configurations on performance.

WEPPP071	Phase Noise Studies at the Advanced Photon Source	simulation, synchrotron, feedback, photon	2873
	N. Sereno, G. Decker, R.M. Lill, B.X. Yang ANL, Argonne, USA
	Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. Phase noise generated primarily by power line harmonics modulating the 352-MHz rf system in the APS storage ring is a dominant source of high- frequency beam motion, both longitudinally and transversely, due to dispersion in the lattice. It also places fundamental limits on the ability to generate picosecond-scale x-ray pulses for fast pump / probe experiments. Measurements using turn-by-turn beam position monitors (BPMs) located at high-dispersion locations are compared and contrasted with results from a dedicated S-band phase detector connected to either a capacitive pickup electrode or a diamond x-ray detector. Horizontal beam position at high-dispersion locations is related directly to beam phase by a very simple relation involving the momentum compaction. Simulation results are used to validate this relationship and to quantify the relation between phase noise on the main rf vs beam arrival time jitter. A. Zholents et al., NIM A 425, 385 (1999).

WEPPP088	Auto-alignment System and CalibrationPprocedure in TPS Girder System	alignment, laser, survey, photon	2918
	W.Y. Lai, J.-R. Chen, M.L. Chen, H.C. Ho, K.H. Hsu, D.-G. Huang, C.K. Kuan, C.-S. Lin, C.J. Lin, H.M. Luo, S.Y. Perng, P.L. Sung, Y.L. Tsai, T.C. Tseng, H.S. Wang, M.H. Wu NSRRC, Hsinchu, Taiwan
	The TPS (Taiwan photon source) project is under construction and will be finished in the December 2012. Considering the floor’s deformation with time and frequent earthquakes at Taiwan, the survey and alignment procedure should be taken quite often. For dealing with these difficulties and improving accuracy of girder’s position, a highly accurate auto-tuning girders system was designed to accomplish the alignment tasks. There are two cells of TPS girders and varied sensor modulus set up for testing the auto-tuning system. The adjustment of the system converges to less than 6um, and the repeatability of the testing is under 10 um. For improving the accuracy of girders position, that is critical thing to make sure all the calibration of sensors modulus correctly and accurately. The calibration procedure about sensor modular and testing results is described in this paper.

WEPPP089	Study of the Combined Controller for Adjusting and Locking a Girder with Micrometer-level at NSRRC	controls, monitoring, feedback, synchrotron	2921
	H.S. Wang, M.L. Chen, W.Y. Lai, S.Y. Perng, Y.L. Tsai, T.C. Tseng NSRRC, Hsinchu, Taiwan J.-R. Chen NTHU, Hsinchu, Taiwan
	A girder control system is proposed to quickly and precisely adjust the displacement and rotating angle of all girders in the storage ring with little manpower at the Taiwan Photon Source (TPS) project at National Synchrotron Research Center (NSRRC). In this control girder system, six motorized cam movers supporting a girder are driven on three pedestals to perform six-axis adjustments of a girder. To increase the nature frequency of a girder, the locking system is applied to promote the stiffness of a girder structure. The locking system consists of six locking mechanisms attached to three inboard pedestals and a locking controller. The study of the girder control system and the locking system control combined are achieving to the positioning with micrometre-level. This paper presents details of the study and tests of the combined controller.

WEPPR014	Recovering Measured Dynamics from a DC Circulating Space-Charge-Dominated Storage Ring	electron, background, space-charge, diagnostics	2967
	W.D. Stem, B.L. Beaudoin, I. Haber, T.W. Koeth UMD, College Park, Maryland, USA
	Funding: This work is supported by the US Dept. of Energy Offices of High Energy Physics and Fusion Energy Sciences, and by the US Dept. of Defense Office of Naval Research and Joint Technology Office. Space-charge is increasingly significant at high beam intensities such as in FEL injectors and heavy ion inertial fusion drivers, where it dominates the beam dynamics. The University of Maryland Electron Ring (UMER) is a high intensity circular machine that is dedicated to the study of long path length space-charge-dominated beam physics on a small scale. Over multiple turns, longitudinal space charge effects cause the tail and head of an electron bunch to expand and interpenetrate, eventually resulting in a “DC beam”. This leads to complications when trying to measure the beam with UMER’s AC coupled diagnostics. Three techniques are developed to recover the information within the beam. Two “knockout” techniques implement invasive pulsed electric kicks to the beam in combination with either a fluorescent imaging screen or a current monitor. A third technique based on integration of the wall-current signal provides a non-invasive method to study the DC beam dynamics. Experimental results from all three methods are compared. The DC beam profile can then be studied over long trajectories and the existence of any loss mechanisms can be determined.

WEPPR046	THz Bursting Thresholds Measured at the Metrology Light Source	electron, synchrotron, vacuum, octupole	3030
	M. Ries, J. Feikes, P.O. Schmid, G. Wüstefeld HZB, Berlin, Germany A. Hoehl PTB, Berlin, Germany
	At the Metrology Light Source (MLS) * of the Physikalisch-Technische Bundesanstalt (PTB) the bunch length can be varied by more than two orders of magnitude *. The bunch length manipulation is achieved by varying different machine parameters, such as rf-voltage amplitude up to 500 kV and the momentum compaction factor over three orders of magnitude. The subject of this article is the measurement of THz bursting thresholds at the MLS for different bunch lengths. B. Beckhoff et al., Phys. Status Solidi B 246, p. 1415 (2009) ** J. Feikes et al., Phys. Rev. ST Accel. Beams 14, 030705 (2011).

WEPPR057	On the Single Bunch Longitudinal Collective Effects in BEPCII	impedance, electron, collective-effects, controls	3054
	D. Wang, Z. Duan, J. Gao, Y. Li, L. Wang, L. Wang, N. Wang IHEP, Beijing, People's Republic of China
	Funding: National Natural Science Foundation of China,project 11175192. In order to study the single bunch longitudinal instability in BEPCII, experiments on the bunch lengthening phenomenon were made. By analyzing the experimental data based on the Gao’s theory, the longitudinal loss factor for the bunch are obtained. Also, the total wake potential and the inductance of the machine are estimated.

WEPPR059	The Simulation of Ion Cloud Build-up in Electron Storage Ring	ion, electron, simulation, space-charge	3060
	X.L. Yu, W. Li, L. Wang USTC/NSRL, Hefei, Anhui, People's Republic of China
	In electron storage rings, positive ions are created by the ionization of the residual gas. Three main collision types including elastic collision, excitation collision and ionization collision are considered in this paper. In order to calculate the probability of the gas ionization using DSMC method, the total cross section, total inelastic cross section, elastic cross section, excitation cross section and ionization cross section are deduced separately. Once ions are created，PIC is adopted to trace the ion，s motion under the combined action due to externally applied field and self-field. The purpose of all study is to present how ion cloud gets to equilibrium little by little.

WEPPR079	Observations of Microbunching Instabilities from a THz Port at Diamond Light Source	radiation, synchrotron, optics, electron	3114
	W. Shields, G.E. Boorman, V. Karataev, A. Lyapin JAI, Egham, Surrey, United Kingdom R. Bartolini, A.F.D. Morgan, G. Rehm Diamond, Oxfordshire, United Kingdom
	Diamond Light source is a third generation synchrotron facility dedicated to producing radiation of outstanding brightness. Above a threshold current, the electron bunches are susceptible to the phenomenon known as the microbunching instability. This instability is characterised by the onset of radiation bursts, the wavelength of which is around one order of magnitude shorter than the bunch length. Near threshold, the bursting occurs quasi-‐periodically, however at higher currents, the bursting appears randomly. The high frequencies involved in these emissions make detection and analysis challenging. A port specifically for the investigation of mm wave emissions has recently been built at Diamond. Ultra fast Schottky Barrier Diode detectors have been installed to obtain data for only a small fraction of the bunch revolution time in an updated data acquisition system. The threshold current and subsequent evolution of the instability have been investigated.

WEPPR082	The Collective Effects of Long Straight Sections (LSSs) in the Advanced Photon Source Upgrade	impedance, undulator, collective-effects, injection	3120
	Y.-C. Chae, L.H. Morrison ANL, Argonne, USA
	Funding: Work supported by U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under contract No. DE-AC02-06CH11357. The Advanced Photon Source is a 7-GeV hard x-ray synchrotron light source. The APS Upgrade specifies additional beamlines delivering higher brightness and flux as well as for the short-pulse x-ray (SPX). In order to fulfill these demands we plan to provide long straight sections (LSS), for which the total length of the insertion devices is increased to 7.7m. The long straight section also helps in implementing the SPX scheme without removing insertion devices. However, the impedance of the LSS may reduce the single-bunch current of 16 mA per bunch delivered to the users during hybrid fill. We estimate the effect of LSS impedance on the bunched beam current and propose an impedance optimization of the undulator chamber with a small gap.

WEPPR083	New Sector 37 Chamber Design and Installation for High-Current Operation of the APS Storage Ring	impedance, vacuum, cavity, HOM	3123
	Y.-C. Chae, R. Bechtold, W. Berg, L. Erwin, M. Givens, J.E. Hoyt, L.H. Morrison, K.M. Schroeder, R. Soliday, J.B. Stevens, G.J. Waldschmidt ANL, Argonne, USA
	Funding: Work supported by U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under contract No. DE-AC02-06CH11357. The Advanced Photon Source is a 7-GeV hard x-ray synchrotron light source consisting of 40 sectors. Sector 37 accommodates four radio-frequency cavities followed by a short straight section, which is set aside for the future installation of a diagnostic device. The 60-cm-long section of spool pieces can be isolated by two gate valves and has an independent vacuum pump. The spool pieces are normally under high vacuum condition when the total current is below 100 mA. However, at the higher current required for the APS Upgrade, rf heating causes an unacceptable rise in temperature. We analyzed this situation by wakefield simulation, which led to a new chamber design. Proper fabrication and careful installation with twelve thermocouples ensured a temperature rise under 40-50 degrees Celsius at 100 mA. A brief thermal analysis shows that the present observed temperature rise in the new chamber is mainly due to the resistive wall.

WEPPR084	Measurement of Coherent Damping Rate of the APS Storage Ring	damping, feedback, kicker, pick-up	3126
	C. Yao, K.C. Harkay, H. Shang, C.-X. Wang ANL, Argonne, USA
	Funding: Work supported by U.S. Department of Energy, Offices of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357. The APS storage ring is a 7-GeV electron storage ring with a single-bunch current of up to 16 mA during normal user operations. To overcome beam instability we employ both chromatic correction and bunch-by- bunch feedback system. Typically we run a chromaticity of 4 for a 24-single fill pattern and 9 for a hybrids fill pattern in both planes with the feedback system loops closed. The APS upgrade (APS-U) calls for a beam current of 150 mA and installation of vertical deflecting cavities for short X-ray (SPX) production. In order to estimate whether the current chromatic correction and feedback system are adequate for the upgrade, we performed coherent damping rate measurements with two methods: kicking the beam with a kicker pulse and exciting the beam with the feedback system. We conclude that with a chromaticity of 4 in both planes, we can achieve a damping rate of 3 kHz in the x- plane and 2 kHz in the y-plane with feedback loops closed. Similar damping rates can also be achieved with chromatic correction alone. A special fitting program was developed to perform the damping rate analysis. This report presents the measurement data and results of the analysis.

WEPPR098	Two Dimensional Impedance Analysis of Segmented IVU	impedance, vacuum, undulator, simulation	3168
	A. Blednykh, G. Bassi, J. Bengtsson, O.V. Chubar, C.A. Kitegi, T. Tanabe BNL, Upton, Long Island, New York, USA
	Funding: Work supported by DOE contract No: DE-AC02-98CH10886 Segmented Adaptive-Gap In-Vacuum Undulator (IVU) with variable magnetic gap along z-axis is considered as an alternative to the Constant Gap IVU (7mm gap) for the NSLS-II storage ring. The length of the Constant Gap IVU for a given minimum gap is limited by the beam stay clear aperture. With the new conceptual design of IVU the magnetic gap can be varied along z-axis and its minimum gap can be reduced down to 5.25mm in the center of the structure for the same stay clear aperture. Beam impedance becomes an important issue since the new design consists of several magnet gaps. Wakepotentials and impedances have been analyzed for a new type of IVU and the results compared with data for the reference geometry which is the Constant Gap IVU.

THXB03	Beam and Spin Dynamics in an Electric Proton EDM Ring	proton, lattice, dipole, quadrupole	3203
	R.M. Talman CLASSE, Ithaca, New York, USA J. Talman BNL, Upton, Long Island, New York, USA
	Electric dipole moment (EDM) measurements may help to answer the question ‘‘Why is there more matter than anti-matter in the present universe?'' For a charged baryon like the proton such a measurement is thinkable only in a ring in which a bunch of protons is stored for more than a few minutes, with polarization ‘‘frozen'' (relative to the beam velocity) and with polarization not attenuated by decoherence. Beam and spin dynamics in an all-electric lattice with these characteristics is described. Rings for other charged baryons, such as deuterons or helium-3 nuclei, are also possible but, requiring both electric and magnetic fields, they are more complicated.
	Slides THXB03 [0.155 MB]

THPPC003	Development of a Broad-band Magnetic Alloy Cavity at GSI	cavity, impedance, coupling, ion	3275
	T.S. Mohite, U. Ratzinger IAP, Frankfurt am Main, Germany R. Balß, P. Hülsmann GSI, Darmstadt, Germany
	FINEMET, a Magnetic Alloy material, is often used to build a broad-band cavity for an accelerator or a storage ring. A research on the broad-band FINEMET cavity is of prime importance not only for the present accelerator facility but also for the future storage rings and synchrotron in upcoming FAIR facility alongside the GSI, Darmstadt. In several measurements, high intensity rare-isotope beams, with lower life time, are demanded at injection energy in Experimental Storage Ring (ESR) at GSI. A longitudinal beam stacking of such beams by means of using a special barrier-bucket RF cavity is found appropriate to serve this purpose. Additionally, this cavity is supposed to provide the compressed bunches at lower energies for HITRAP, an ion-trap facility for experiments with highly charged ions, in FAIR. Several measurements are being performed, along with the theoretical analysis, to achieve the designed parameters for the planned barrier-bucket cavity. 60 FINEMET ring cores have been tested to confirm their designed electrical properties. Some of these ring cores are then loaded, in steps, in a test cavity, which will further be used as the barrier-bucket cavity for the ESR. C. Dimopoulou et al., JACoW Proceedings of COOL 2007, Bad Kreuznach, Germany

THPPC016	PLSII Linac RF Conditioning Status	linac, klystron, high-voltage, vacuum	3311
	H.-S. Lee, J.Y. Huang, W.H. Hwang, H.-G. Kim, K.R. Kim, S.H. Kim, S.H. Kim, S.H. Nam, W. Namkung, S.S. Park, S.J. Park, Y.J. Park, S. Shin PAL, Pohang, Kyungbuk, Republic of Korea
	PLS linac has been upgraded in energy from 2.5 to 3.0 GeV. A klystron supplies RF power of 80 MW four acceleration structures through a SLED. But our machine is not enough RF power to get 3 GeV beam energy. So we have changed the RF scheme in four modules as a klystron supplies RF power of 80 MW two accelerating structures through a SLED. There were several problems during the RF conditioning and beam operation. So we will describe the conditioning results and the current status in this paper.

THPPC036	The Alpha Ferrite-loaded Coaxial Resonator Cavity	cavity, damping, resonance, radiation	3365
	A.N. Pham, S.-Y. Lee, T.H. Luo IUCEEM, Bloomington, Indiana, USA
	Funding: Grant N00164-08-GM03 P00004 from the NSWC Crane Division, DOE Grant DE-FG02-92ER40747, and NSF Grant PHY-0852368 (IU: 48-432-31). The Advanced Electron Photon Facility (ALPHA),* is a joint collaboration between the Indiana University Center for Exploration of Energy and Matter and the Crane Naval Surface Warfare Center. The ALPHA storage ring will serve as a debuncher in single pass mode of operation. With a set of two gradient damping wigglers, the storage ring can also accumulate to achieve high charge density beams. In this report, we present the design, fabrication, and testing of the 15 MHz ferrite-loaded quarter-wave rf coaxial resonator cavity that will be utilized in the ALPHA storage ring. Topics pertaining to beam lifetime, radiation damping, ferrite-loaded transmission lines, and key cavity parameters will be discussed. * S.Y. Lee, P.E. Sokol, et al, "The ALPHA Project at IU CEEM," Proceedings of the IPAC2010. ** S.Y. Lee, et al, "A low energy electron storage ring with tunable compaction factor," RSI 78, 2007.

THPPC052	Commissioning and One Year Operation of the 50 kW Solid State Amplifiers of the LNLS Storage Ring RF System	klystron, controls, booster, synchrotron	3404
	R.H.A. Farias, J.F.F. Ferrari, C. Pardine, F. Santiago de Oliveira LNLS, Campinas, Brazil
	In December 2010 a pair of high power solid state amplifiers was installed in the RF system of the LNLS electron storage ring. The new amplifiers replaced the UHF klystron system that had been in operation since the machine started operating in 1996. LNLS has been working on solid state amplifiers for more than 10 years since it started a close collaboration with LURE back in 1999 to build an amplifier to drive the booster RF system. From this ongoing collaboration with SOLEIL resulted the design and construction of these two new high power amplifiers, capable of delivering up to 50 kW each at the operating frequency of 476 MHz. Before installation the amplifiers were commissioned in the RF laboratory. We present an overview of the results of those tests as well as a performance evaluation after one year operation of the amplifiers in the storage ring.

THPPD012	Measurement of Injection System of AC Septum Magnets for TPS Storage Ring	septum, injection, shielding, vacuum	3521
	F.-Y. Lin, C.-H. Chang, C.-S. Fann, C.-S. Hwang, C.S. Yang NSRRC, Hsinchu, Taiwan
	Taiwan Photon Source (TPS) is a 3 GeV third generation light source and will be operated in top-up injection mode. The leakage field of the septum magnet will dominate the injection performance. The septum magnets, parts of injection system, consist of AC and DC current mode magnets. The AC septum magnet were designed and constructed by NSRRC. In order to verify the magnetic field quality and the leakage field distribution, the search coil probe and the printed circuit technology for long coil probe measurement systems are developed and implemented for magnetic field measurement. This paper will describe the magnetic field measurement system, the magnetic field mapping results and the field shielding performance of AC septum magnet.

THPPD015	Character and Performance of Magnets for the TPS Storage Ring	sextupole, multipole, quadrupole, dipole	3527
	J.C. Jan, C.-H. Chang, H.-H. Chen, Y.L. Chu, C.-S. Hwang, C.Y. Kuo, F.-Y. Lin, C.S. Yang, Y.T. Yu NSRRC, Hsinchu, Taiwan
	The Taiwan Photon Source (TPS) is a third-generation light source. The orbit of the electron beam will be controlled with 48 dipoles, 240 quadrupoles, 168 sextupoles and several correctors in the storage ring. The construction of the first magnets for one sector, including prototype magnets, is to be completed during 2011 December. The mechanical dimensions of these magnets have been examined on a precise 3D-coordinate-measuring machine (CMM). The field strength, effective length and multipole errors were inspected with a rotating-coil measurement system (RCS) and a Hall-probe measurement system (HPS). The field center of the quadrupole and sextupole magnets is shimmed with a precise shimming block on the RCS bench. The inaccuracy of the position of the field center will be within 0.01 mm after shimming the feet. This work reports the current status, the construction performance, the mechanical shimming algorithm and the relative construction issue of the high precision magnet.

THPPD037	Design Studies of a Dipole with Elliptical Aperture for the Muon Collider Storage Ring	dipole, collider, quadrupole, electron	3590
	M.L. Lopes, V. Kashikhin, J.C. Tompkins, A.V. Zlobin Fermilab, Batavia, USA R.B. Palmer BNL, Upton, Long Island, New York, USA
	Funding: Work supported partially by US-MAP and by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy The requirements and operating conditions for superconducting magnets used in a Muon Collider Storage Ring are challenging. About one third of the beam energy is deposited along the magnets by the decay electrons. As a possible solution an elliptical tungsten absorber could intercept the decay electrons and absorb the heat limiting the heat load on superconducting coils to the acceptable level. In this paper we describe the main design issues of dipoles with an elliptical aperture taking into consideration the field and field quality. The temperature margin and the forces in the coils are presented as well.

THPPD067	Performance of Kicker Pulsers for TPS Project	kicker, injection, power-supply, booster	3665
	C.-S. Fann, C.-T. Chen, K.T. Hsu, S.Y. Hsu, J.C. Huang, K.-K. Lin, K.-B. Liu, H.M. Shih, K.L. Tsai NSRRC, Hsinchu, Taiwan
	A set of kicker power suppliers has been designed and fabricated for storage ring beam injection of the Taiwan Photon Source (TPS) project. In order to fulfill the requirements, the performance of the designed units has been bench tested and the results are examined. The matching in four pulsers, the pulse-to-pulse stability and the time jitter are specified according to the beam injection requirements. The engineering evaluation and the measurement results are briefly discussed.

THPPP002	Operation of the HESR Storage Ring of the FAIR Project with Ions and Rare Isotopes	ion, target, electron, antiproton	3722
	M. Steck, C. Dimopoulou, A. Dolinskii, T. Katayama, Yu.A. Litvinov, T. Stöhlker GSI, Darmstadt, Germany R. Maier, D. Prasuhn, H. Stockhorst FZJ, Jülich, Germany
	The HESR storage ring of the FAIR project is designed for experiments with cooled antiprotons. The HESR receives pre-cooled antiprotons from the Collector Ring CR which is also designed for cooling of rare isotope beams. The magnetic rigidity of 13 Tm is the same for the pre-cooling of antiprotons and rare isotopes in the CR. Therefore the transfer of ions or rare isotopes from the CR to the HESR can be performed under similar condition, except the different polarity of the magnetic components. This is an option for the first stage of the FAIR project when no other storage ring is available for experiments with stored ions. In the HESR the ions can be decelerated or accelerated, like the antiprotons, to energies corresponding to the magnetic rigidity range from 5 to 50 Tm. The planned beam cooling systems of the HESR, stochastic and electron cooling, can be applied to improve the quality of the ion beams in the HESR and support experiments using an internal target or the accumulation of rare isotope beams in the HESR. Scenarios for operating the HESR with ions and rare isotopes as well as achievable performance, beam intensity and quality for internal experiments will be discussed.

THPPR001	Setting Generation for FAIR	controls, synchrotron, proton, optics	3963
	D. Ondreka, J. Fitzek, H. Liebermann, R. Müller GSI, Darmstadt, Germany
	The experimental program envisaged for the Facility for Antiproton and Ion Research (FAIR) requires complex operation schemes of its accelerators and beamlines including parallel operation of several experiments. Thus, there is a strong need to develop an appropriate setting generation system, which shall supply consistent settings for all devices across the facility to support the planned parallel operation modes. This system should also provide standard tools for modifying and accessing the settings. These requirements will be met by using LSA, a generic accelerator modeling framework developed at CERN, as basis for the setting generation system. We will report on the status of the setting generation system for FAIR, covering both the implementation of the physics model as well as the extensions to the LSA framework realized within a collaboration with CERN. Results of the first test runs with the existing GSI synchrotron SIS18 will be presented.

THPPR028	Telephone Alarm Broadcasting for TPS RF System	monitoring, SRF, synchrotron, status	4026
	Y.-H. Lin, L.-H. Chang, M.H. Chang, L.J. Chen, F.-T. Chung, M.-C. Lin, Ch. Wang, M.-S. Yeh, T.-C. Yu NSRRC, Hsinchu, Taiwan
	The Taiwan Photon Source (TPS) consists of three 500-MHz RF systems: two sets RF systems with KEKB-type single-cell SRF modules are used for the 3-GeV storage ring, and one with five-cell Petra cavities at room temperature is used for booster synchrotron. To monitor the status of the RF systems and to broadcast the error/alarm messages to the RF guys, we develop a telephone alarm broadcasting system. This introduces the hardware and software structure of the alarm broadcasting system.

THPPR034	Safety Interlock Implementation of Top-up Operation in the SSRF Control System	controls, injection, booster, linac	4044
	L.R. Shen, G.H. Chen, J.F. Chen, W.D. Fang SINAP, Shanghai, People's Republic of China
	The SSRF has performed two years stable operation on decay mode. In order to realize the Top-up operation, the upgrade of control system has been carried out for Top-up trial run. Control system sets up the operation mode control center and accomplishes the upgrading of the MPS system. According to the requirements of the physical design, control system accomplished the design and implementation of the interface for interoperate with PPS system, beam diagnosis system and power supply system and set up the interlocks of the radiation dose, energy, injection efficiency, beam current and beam life in Top-up mode. The kernel of top-up operation safety interlock system is based on hardware interlock system and also provides software interlocking as auxiliary. In the meantime, the reliability of software interlock has been improved.

THPPR057	Feasibility Study Gamma-induced Positron Annihilation Lifetime Spectroscopy in an Electron Storage Ring	laser, positron, electron, target	4103
	Y. Taira, H. Toyokawa AIST, Tsukuba, Ibaraki, Japan M. Adachi, M. Katoh, S. Tanaka UVSOR, Okazaki, Japan N. Yamamoto Nagoya University, Nagoya, Japan
	Funding: This work was supported by Grants-in-Aid for Scientific Research (22360297) and Grant-in-Aid for JSPS Fellows (235193). Positron annihilation lifetime spectroscopy (PALS) has proved to be very sensitive tool to characterize materials and study defects. However PALS has been restricted to thin samples because of the limited range of positrons in materials. We have developed new techniques for PALS, in which laser Compton scattered (LCS) gamma rays are used to produce positrons inside materials via pair production. Ultra-short gamma ray pulse source* with pulse width of 5 ps (FWHM) generated by 90-degree collision LCS was applied to PALS for the first time. The short pulse width of the gamma-rays that is negligible compared to estimated positron lifetime (100 ps to ns range) is essential to PALS. The experiment was carried out at the UVSOR-II electron storage ring, a 750 MeV synchrotron light source. The positron annihilation lifetime, 199 ± 10 ps, in a bulk sample of lead was successfully measured by using the ultra-short gamma ray pulse. * Y. Taira, et al., Nucl. Instr. And Meth. A 637 (2011) S116.

Paper

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Other Keywords

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MOYBP01

State-of-the-Art and Future Prospects in RF Superconductivity

cavity, SRF, niobium, electron

11

K. Saito
KEK, Ibaraki, Japan

This presentation should recount the remarkable progress in improving the performance of superconducting cavities over the past 50 years and explore future directions, including advances in materials other than Nb, such as MgB2 and novel multi-layer superconductor-insulator systems. This talk should provide an overview of international activities.

Slides MOYBP01 [10.097 MB]

MOPPC060

Investigations into Beam Life Time in Low Energy Storage Rings

ion, target, electron, antiproton

271

A.I. Papash, A.V. Smirnov
MPI-K, Heidelberg, Germany
A.I. Papash
JINR, Dubna, Moscow Region, Russia
C.P. Welsch
Cockcroft Institute, Warrington, Cheshire, United Kingdom

Funding: Work supported by the Helmholtz Association of National Research Centers and GSI under contract VH-NG-328.
In low energy storage rings, beam life time critically depends on the residual gas pressure, scattering effects caused by in-ring experiments and the available machine acceptance. A comprehensive simulation study into these effects has been realized with a focus on the TSR storage ring in Heidelberg and the electrostatic rings ELISA, the AD recycler and the ultra-low energy storage ring (USR). This was done by using the computer code BETACOOL in combination with the OPERA-3D and MAD-X programs. In this contribution, the results from these studies are presented and compared to available experimental data. Based on these simulations, criteria for stable ring operation are then presented.

MOPPC078

Simulation Studies of Injection Scheme in TPS Storage Ring

injection, lattice, simulation, alignment

316

Y.C. Lee, H.-P. Chang, P.J. Chou
NSRRC, Hsinchu, Taiwan

Funding: NSRRC, Hsinchu, Taiwan.
The baseline lattice of TPS storage ring was finalized in October 2009. Later upon users’ request, we plan to implement the double mini-βy lattice in three 12-m straight sections of TPS storage ring. These locations were chosen to maintain the symmetry of the storage ring lattice. Particle tracking for the first few turns were used to check the injection scheme of storage ring, including errors introduced in manufacturing and installation process. Results of simulation studies will be presented.

MOPPD001

Accelerator R&D in the QUASAR Group

antiproton, diagnostics, niobium, instrumentation

364

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

Funding: Work supported by the Helmholtz Association and GSI under contract VH-NG-328, the EU under contracts PITN-GA-2008-215080, PITN-GA-2011-289191, PITN-GA-2011-289485 and STFC.
The QUASAR Group was founded in 2007 with an initial focus on the development and experimental exploitation of a novel electrostatic ultra-low energy storage ring (USR), part of the future facility for low-energy antiproton and ion research (FLAIR). The group's research activities have grown considerably over the past four years and now include also the development of beam diagnostic tools for accelerators and light sources, investigations into superconducting linear accelerators and medical applications, and, most recently, a broad R&D program into laser applications at accelerators. In this contribution, an overview of the QUASAR Group’s research achievements to date is given.

MOPPD002

Ultra-low Energy Storage Ring at FLAIR

extraction, antiproton, ion, lattice

367

C.P. Welsch, D. Newton, M.R.F. Siggel-King
Cockcroft Institute, Warrington, Cheshire, United Kingdom
O.E. Gorda, O. Karamyshev, G.A. Karamysheva, M. Panniello, A.I. Papash, A.V. Smirnov
MPI-K, Heidelberg, Germany
J. Harasimowicz, M. Putignano, C.P. Welsch
The University of Liverpool, Liverpool, United Kingdom

Funding: The support of the HGF and GSI under contract VH-NG-328, the EU under contract PITN-GA-2008-215080, the Max Planck Institute for Nuclear Physics and the STFC Grant ST/G008248/1 is acknowledged.
The Ultra-low energy electrostatic Storage Ring (USR) at the future Facility for Low-energy Antiproton and Ion Research (FLAIR) will provide cooled beams of antiprotons in the energy range between 300 keV down to 20 keV. Based on the original design concept developed in 2005, the USR has been completely redesigned over the past few years. The ring structure is now based on a 'split achromat' lattice. This ensures compact ring dimensions of 10 x 10 m, whilst allowing both, in-ring experiments with gas jet targets and studies with extracted beams. In the USR, a wide range of beam parameters will be provided, ranging from very short pulses in the nanosecond regime to a coasting beam. In addition, a combined fast and slow extraction scheme was developed that allows for providing external experiments with cooled beams of different time structure. Furthermore, studies into beam diagnostics methods for the monitoring of ultra-low energy ions at beam intensities less than 10⁶ were carried out. Here, we present the USR design with an emphasis on the expected beam parameters available to the experiments at FLAIR.

MOPPD071

Error Localization in RHIC by Fitting Difference Orbit

feedback, closed-orbit, dipole, optics

526

C. Liu, M.G. Minty, V. Ptitsyn
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Many errors in an accelerator are evidenced as transverse kicks to the beam, which distort the beam trajectory. Therefore, the information of the errors are imprinted in the distorted orbits, which are different from what would be predicted by the optics model. In this paper, we introduce an algorithm for fitting the orbit based on an on-line optics model. We apply the algorithm to localize the location of the elusive source of vertical diurnal variations observed in RHIC, and analyze D0/Dx errors in local coupling measurement.

MOPPP004

Further Study on Fast Cooling in Compton Storage Rings

laser, electron, simulation, photon

571

E.V. Bulyak
NSC/KIPT, Kharkov, Ukraine
J. Urakawa
KEK, Ibaraki, Japan
F. Zimmermann
CERN, Geneva, Switzerland

Compton sources can produce gamma-ray photons of ultimate intensity, but suffer from the large recoils experienced by the circulating electrons scattering off the laser photons. We have previously proposed a scheme called asymmetric fast cooling to reduce the beam energy spread in Compton rings. This report presents results of further studies on the fast cooling. In particular, we show that (1) a proper asymmetric setup of the scattering point results in significant reduction of the quantum losses of electrons in Compton rings with moderate energy acceptance, and (2) the optimized pulsed mode of operation in synchrotron-dominated rings enhances the overall performance of such gamma-ray sources. Theoretical results presented are in good accordance with numerical simulations. We discuss the performance of an existing storage ring such as KEK ATF DR equipped with an optical cavity and presently available laser system.

MOPPP051

NSLS-II Transport Line Progress

booster, linac, diagnostics, injection

676

R.P. Fliller, A.T. Anderson, B. Benish, W. DeBoer, G. Ganetis, R. Heese, H.-C. Hseuh, J. Hu, M.P. Johanson, B.N. Kosciuk, D. Padrazo, K. Roy, T.V. Shaftan, O. Singh, J.L. Tuozzolo, B. Wahl, G.M. Wang
BNL, Upton, Long Island, New York, USA

Funding: This manuscript has been authored by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The National Synchrotron Light Source II (NSLS-II) is a state-of-the-art 3-GeV third generation light source currently under construction at Brookhaven National Laboratory. The NSLS-II injection system consists of a 200 MeV linac, a 3-GeV booster synchrotron and associated transfer lines. The first part of the Linac to Booster Transport (LBT) line has been installed for linac commissioning. This part includes all components necessary to commission the NSLS-II linac. The second part of this transport line is undergoing installation. Initial results of hardware commissioning will be discussed. The Booster to Storage Ring (BSR) transport line underwent a design review. The first part of the BSR transport line, consisting of all components necessary to commission the booster will be installed in 2012 for booster commissioning. We report on the final design of the BSR line along with the plan to commission the booster.

MOPPP053

Failure Mode Analysis in Preparation for Top-up Injection at the Canadian Light Source (CLS)

injection, dipole, kicker, simulation

682

L.O. Dallin
CLS, Saskatoon, Saskatchewan, Canada

Top-up injection involves injecting beam with beamline safety shutters open. Consequently it is extremely important that no electrons enter the beamlines where they could be a potential safety hazard to beamline personnel. To investigate the likelihood that electrons could exit the storage ring various failure mode simulations have been done. The approach is to account for all possible injection trajectories and show that these particles will be intercepted by various storage ring apertures before they reach an amplitude that is deemed unsafe. This amplitude was chosen to be 50 mm and the field roll-off of all storage ring magnets were defined to this amplitude. Failure modes invested included injection kicker failures, uncorrected misalignment errors, off-energy injection and shorted storage ring magnet coils. Errors that would render it impossible to store beam were not investigated. As some particles reached amplitudes beyond the safe limit measures have been devised to eliminate these unsafe scenarios.

MOPPP054

Study of a New Injection Scheme for the SSRF Storage Ring

injection, kicker, emittance, dynamic-aperture

685

M.Z. Zhang, B.C. Jiang, L. Ouyang, Q.L. Sun, S.Q. Tian
SINAP, Shanghai, People's Republic of China

A low emittance configuration of the SSRF storage ring had been designed and commissioned. Along with reducing the emittance, the dynamic aperture decreases quickly. It doesn’t meet aperture require of the normal injection scheme anymore and the injection efficiency is lower. The pulsed multi-pole magnets give the opportunity to overcome the smaller dynamic aperture. Pulsed quadrupole and sextupole both are study for the injection scheme. With and without the orbit bump kickers are also considered in this study. The injection scheme suggestions are presented in this paper.

MOPPP066

Calculated Spectra from Magnetic Field Measurements of 1.5 m Superconducting Undulator Coils

undulator, emittance, permanent-magnet, vacuum

711

S. Casalbuoni, T. Baumbach, S. Gerstl, A.W. Grau, M. Hagelstein, T. Holubek, D. Saez de Jauregui
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
C. Boffo, W. Walter
BNG, Würzburg, Germany

In this contribution we report on the spectra calculated from the field measurements performed in a liquid helium bath of 1.5 m superconducting undulator coils. The coils are foreseen for a superconducting undulator demonstrator with a period length of 15 mm planned to be installed in ANKA middle 2012 and tested at the new beamline NANO for high resolution X-ray diffraction. The spectral performance at ANKA and at low emittance sources is compared with the competing cryogenic permanent magnet technology.

MOPPP068

Beam Heat Load and Pressure in the Superconducting Undulator Installed at ANKA

electron, undulator, vacuum, simulation

717

S. Casalbuoni, S. Gerstl, A.W. Grau, T. Holubek, D. Saez de Jauregui
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany

A superconducting undulator has been installed in the ANKA (ANgstrom source KArlsruhe) storage ring since March 2005. The beam heat load and pressure on the cold bore were analyzed in the first two years of operation, during which the undulator was operated mainly with open gap. We report here on a larger statistic of beam heat load and pressure data collected in the last years with the undulator operated at different gap positions. The effects of vacuum leaks in the storage ring on the superconducting undulator operation are also described.

MOPPP070

Characterization of Vacuum Chamber Samples for Superconducting Insertion Devices

vacuum, undulator, insertion, insertion-device

723

D. Saez de Jauregui, T. Baumbach, S. Casalbuoni, S. Gerstl, A.W. Grau, M. Hagelstein, C. Heske, T. Holubek, B. Krause, A. Seiler, S. Stankov, L. Weinhardt
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
C.Z. Antoine, Y. Boudigou
CEA/IRFU, Gif-sur-Yvette, France
C. Boffo
BNG, Würzburg, Germany

One of the key components of a superconducting insertion device is the ultra-high vacuum (UHV) chamber. In order to reach the accelerator UHV specifications, it is very important to control the surface chemical content and find proper cleaning procedures. To keep the geometric and resistive wall losses small, it is essential that the top few μm of the surface exhibits low roughness and good electrical conductivity at low temperatures. A 300-μm-thick 316L stainless steel foil, galvanized with a 30-μm copper layer, is used for the next superconducting undulator developed in a collaboration between KIT and BNG. We report here on different spectroscopic analyses as well as on residual resistivity ratio RRR measurements of the copper surface after cleaning procedures and annealing at various temperatures for different periods of time.

MOPPP091

Recent Developments at the DELTA THz Beamline

laser, electron, radiation, undulator

768

P. Ungelenk, M. Bakr, H. Huck, M. Höner, S. Khan, R. Molo, A. Nowaczyk, A. Schick, M. Zeinalzadeh
DELTA, Dortmund, Germany

Funding: Work supported by DFG, BMBF, and by the Federal State NRW.
During 2011, a new dedicated THz beamline has been constructed and commissioned at DELTA, a 1.5 GeV synchrotron light source operated by the TU Dortmund University. This beamline enables extracting and detecting coherent THz pulses caused by a laser-induced density modulation of the electron bunches. Ongoing experiments aim at characterizing the THz radiation as well as investigating the evolution of the density modulation over subsequent revolutions following the initial laser-electron interaction in an undulator.

MOPPR001

Resonant Spin Depolarisation Measurements at the SPEAR3 Electron Storage Ring

electron, lattice, polarization, synchrotron

771

K.P. Wootton, R.P. Rassool
The University of Melbourne, Melbourne, Australia
M.J. Boland, Y.E. Tan
ASCo, Clayton, Victoria, Australia
W.J. Corbett, M.H. Donald, X. Huang, R.R. Ortiz, J.A. Safranek, K. Tian
SLAC, Menlo Park, California, USA

Accurate electron beam energy measurements are valuable for precision lattice modelling of high-brightness light sources. At SPEAR3 the beam energy was measured using the resonant spin depolarisation method with striplines to resonantly excite the spin tune and a sensitive NaI scintillator beam loss monitor was used to detect resulting changes in Touschek lifetime. Using the combined apparatus an electron beam energy of 2.997251(7) GeV was measured, giving a relative uncertainty better than 3x10^-6. The measured momentum compaction factor was found to be in close agreement with the numerical model value using rectangular defocussing gradient dipoles with measured magnetic field map profiles. In this paper we outline the chosen experimental technique, with emphasis on its applicability to electron storage rings in general.

MOPPR031

BPM Data Processing Based on EPICS Soft IOC at HLS

EPICS, brilliance, injection, controls

846

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

A data analysis program has been developed and verified successfully for the new beam position monitor (BPM) system of the storage ring at Hefei Light Source (HLS). The new BPM system will be equipped with Libera Brilliance BPM processors in the upgrade project of HLS. The embedded system on Libera has completed some basic work, including data acquisition, position calculation, and EPICS IOC data output. A new record type was developed to accomplish the beam position recalculation by log-ratio method. The new position signal’s character was studied in the time and frequency domain, including distribution, RMS noise, spectrum, tune, digital filter, signal correlation, etc. Recalculation beam position showed higher sensitivity and greater linear range.

MOPPR032

Electron Beam Diagnostics based on Transverse Feedback System at Duke Storage Ring

feedback, electron, monitoring, FEL

849

W. Xu, D.H. He
USTC/NSRL, Hefei, Anhui, People's Republic of China
J.Y. Li, W. Wu, 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.
To combat electron beam instabilities, a field programmable gate array (FPGA) based bunch-by-bunch transverse feedback (TFB) has been developed for the Duke storage ring. While it is capable of suppressing transverse beam instabilities for multi-bunch operation, the TFB system has not been needed for typical operation of the Duke storage ring FEL. To explore the great potential of this system, we have focused on the development of TFB based beam diagnostics. A TFB based tune measurement system has been developed using two methods: the tune scan method and tune monitoring method. With the tune monitoring method, a much faster method of the two, we have studied the tune stability of the electron beam in the Duke storage ring. This tune measurement system also allows us to conduct chromaticity measurements more quickly, compared with the existing chromaticity measurement system using a network analyzer. Finally, the TFB based tune system has been used to calibrate the tune knob and chromaticity knob for the Duke storage ring.

MOPPR051

TLS Transportline BPM Upgrade

injection, booster, EPICS, diagnostics

897

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

There are seven stripline beam position monitor (BPM) installed in TLS booster to storage ring transport line. In order to provide the BPM system with better performance and functionalities, the latest generation BPM electronics Libera SinglePass had been adopted in TLS transport line for these stripline BPM. One unit had been tested in early 2011 and delivered the reliable and satisfactory results therefore extra six units had been purchased later. Currently, all of the new 7 units have replaced the past BPM electronics. The application had also been continuously developed. On the other hand, it is expected that the upgrade could enhance diagnostic functionalities for the related injection study. In this report, the injection stability and efficiency had been investigated.

MOPPR053

Improvement of BPM System for the Siam Photon Source

shielding, photon, synchrotron, controls

903

P. Songsiriritthigul, S. Boonsuya, S. Klinkhieo, P. Klysubun, S. Krainara, P. Sudmuang, N. Suradet
SLRI, Nakhon Ratchasima, Thailand
J.-R. Chen, H.P. Hsueh, Y.-H. Liu
NSRRC, Hsinchu, Taiwan
S. Rujirawat, P. Songsiriritthigul
Suranaree University of Technology, Nakhon Ratchasima, Thailand

The Siam Photon Source (SPS) is the first synchrotron light source ever built by modifying and relocating a light source from one country to another. The SPS produced its first light in Dec 2001. The machine has been used to provide regularly synchrotron light for users since 2005. Systematic studies and investigations of the machine have properly been carried out under the supervision of the International Advisory Committee of SLRI in the last two years. This report describes the improvement of the beam position monitoring (BPM) system for the 1.2 GeV storage ring of SPS. The efficiency and reliability of the original BPM system was greatly hindered by the low quality signal cables. The replacement with the higher quality (lower loss and better interference shielding) BPM cables and the implementation of a separated cable tray for the BPM cables have significantly improved the quality of the BPM signals, allowing the possibilities for machine study and thus providing further improvement of the machine. Detailed descriptions of the work on the BPM electronic boards will be described. The measurement results before and after the improvement of the BPM system will also be presented.

MOPPR054

Beam Size Measurement at Siam Photon Source Storage Ring

synchrotron, monitoring, radiation, photon

906

P. Sudmuang, N. Deethae, P. Klysubun, S. Krainara, T. Poolampong, K. Sitisart, N. Suradet
SLRI, Nakhon Ratchasima, Thailand

Synchrotron radiation interferometer and direct imaging setups have been installed and subsequently utilized to investigate transverse beam profile at the Siam Photon Source (SPS). Details of the optical setup as well as the beam sizes determined from the measurement will be presented. Comparison between the measured and theoretical values as established by linear optics calibration will be made and discussed. In order to demonstrate the beam profiling capability of the interferometer and direct imaging systems, measurements with different operating parameters have been carried out and the results will be presented as well.

TUOAB01

Timing and Synchronization for the APS Short Pulse X-ray Project

laser, cavity, feedback, LLRF

1077

F. Lenkszus, N.D. Arnold, T.G. Berenc, G. Decker, E.M. Dufresne, R.I. Farnsworth, Y.L. Li, R.M. Lill, H. Ma
ANL, Argonne, USA
J.M. Byrd, L.R. Doolittle, G. Huang, R.B. Wilcox
LBNL, Berkeley, California, USA

Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
The Short-Pulse X-ray (SPX) project, which is part of the APS upgrade, will provide intense, tunable, high-repetition-rate picosecond x-ray pulses through the use of deflecting cavities operating at the 8th harmonic of the storage-ring rf. Achieving this picosecond capability while minimizing the impact to other beamlines outside the SPX zone imposes demanding timing and synchronization requirements. For example, the mismatch between the upstream and downstream deflecting cavities' rf field phase is specified to be less than 0.077 degrees root mean squared (rms) at 2815 MHz (~77 femtoseconds). Another stringent requirement is to synchronize beamline pump-probe lasers to the SPX x-ray pulse to 400 femtoseconds rms. To achieve these requirements we have entered into a collaboration with the Beam Technology group at LBNL. They have developed and demonstrated a system for distributing stable rf signals over optical fiber capable of achieving less than 20 femtoseconds rms drift and jitter over 2.2 km over 60 hours*. This paper defines the overall timing/synchronization requirements for the SPX and describes the plan to achieve them.
* R. Wilcox et al. Opt. Let. 34(20), Oct 15, 2009

Slides TUOAB01 [2.515 MB]

TUOBB02

Commissioning of the PLS-II

insertion, insertion-device, power-supply, lattice

1089

S. Shin, J.Y. Choi, T. Ha, J.Y. Huang, I. Hwang, W.H. Hwang, Y.D. Joo, C. Kim, D.T. Kim, D.E. Kim, J.M. Kim, M. Kim, S.H. Kim, S.-C. Kim, S.J. Kwon, B.-J. Lee, E.H. Lee, H.-S. Lee, H.M. Lee, J.W. Lee, S.H. Nam, E.S. Park, I.S. Park, S.S. Park, S.J. Park, Y.G. Son, J.C. Yoon
PAL, Pohang, Kyungbuk, Republic of Korea
J-Y. Kim, B.H. Oh
KAERI, Daejon, Republic of Korea
J. Lee
POSTECH, Pohang, Kyungbuk, Republic of Korea

The Pohang Light Source (PLS) has operated for 14 years successfully. To meet the request of the increasing user community, the PLS-II that is the upgrade project of PLS has been completed. Main goals of the PLS-II are to increase beam energy to 3 GeV, to increase number of insertion devices by the factor of two (20 IDs), to increase beam current to 400 mA and to reduce beam emittance below 10 nm with existing PLS tunnel and injection system. The PLS-II had been commissioned over the six months. During commissioning, we achieved 14 insertion devices operation and top-up operation with 100 mA beam current and 5.8 nm beam emittance. In this presentation, we report the experimental results from the PLS-II commissioning.

Slides TUOBB02 [3.484 MB]

TUEPPB008

Status Report on the Iranian Light Source Facility Project

booster, cavity, synchrotron, dipole

1131

J. Rahighi, H. Ajam, R. Aslani, S. Fatehi, H. Ghasem, M.R. Khabazi, R. Safian, E. Salimi, A. Shahveh
IPM, Tehran, Iran
E. Ahmadi, M. Jafarzadeh, H.B. Jalali, M. Moradi, S. Pirani, M. Rahimi, A. Sadeghipanah, F. Saeidi, Kh.S. Sarhadi, A. Shahverdi
ILSF, Tehran, Iran
D. Einfeld
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

The Iranian Light Source Facility Project (ILSF) is a 3rd generation light source with an energy of 3 GeV,a full energy injector and a 100 MeV linac as preinjector. For storage ring, booster synchrotron and linac including the transfer lines, a draft design has been completed and will be presented. The storage ring has an emittance of 3.3 nm-rad, a circumference of 297.6 meters with an overall of 32 straight sections of different lengths. The booster synchrotron has a circumference of 197 meters and emittance of 35nm-rad. For the booster synchrotron a new lattice is proposed. The linac is a conventional 150 MeV accelerator. The different accelerator components, magnets, girders, power supplies, vacuum systems etc. are in the design phase. State of the art design for different components is employed through international collaboration.

TUPPC016

Progress of Emittance Coupling Correction at the SPring-8 Storage Ring

coupling, resonance, betatron, survey

1191

M. Takao, M. Masaki, Y. Shimosaki, K. Soutome, S. Takano, C. Zhang
JASRI/SPring-8, Hyogo-ken, Japan

The vertical beam spread, or the emittance coupling, is one of the most important parameters for the high brilliance light source storage ring. By the precise alignment of the magnets and the proper COD correction, at the commissioning phase of the SPring-8 storage ring we succeeded in achieving the very small coupling ~0.2 % without correction. However, the coupling had grown large with the years, so recently we have corrected it and recovered the initial performance. The scheme of the coupling correction at the SPring-8 storage ring is the global one, which is based on the perturbation theory with single resonance approximation. In the beginning of the correction the coupling was corrected by means of minimizing the vertical beam size. Then the performance of the coupling correction has been further improved by changing the scheme to minimizing the betatron coupling mode in the vertical oscillation of the horizontally kicked beam. This result implies that the higher order coupling contributes to the emittance coupling, which can be corrected by the higher skew multi-pole magnet. The present status of the coupling correction at the SPring-8 storage ring will be reported.

TUPPC025

Solaris Storage Ring Lattice Optimization with Strong Insertion Devices

lattice, optics, undulator, insertion

1218

A.I. Wawrzyniak, C.J. Bocchetta
Solaris, Kraków, Poland
M. Eriksson, S.C. Leemann
MAX-lab, Lund, Sweden

Funding: Work supported by the European Regional Development Fund within the frame of the Innovative Economy Operational Program: POIG.02.01.00-12-213/09
The Solaris synchrotron light facility under construction in Kraków will be a replica of the 1.5 GeV storage ring of MAX IV. This compact 3rd generation light source has been designed to have an emittance of 6 nmrad and operate with 500 mA stored current for VUV and soft X-Rays production. The lattice design consists of 12 Double Bend Achromats (DBA) with each DBA cell integrated into one solid iron block. Twelve 3.5 m long straight sections are available of which 10 will be equipped in various insertion devices. These devices will differ from those adopted by MAX IV. For X-ray production one or more superconducting wigglers will be used, while APPLE II type undulators will be used for variable polarised light production. The linear and nonlinear lattice dynamics have been studied with these perturbing insertion devices included in the ring and results are presented in this paper.

TUPPC047

New Storage Ring Lattice for the Duke FEL Wiggler Switchyard System

wiggler, lattice, FEL, quadrupole

1272

H. Hao, J.Y. Li, 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.
The Duke storage ring is a dedicated drive for the OK-4 FEL and OK-5 FEL, and for the state-of-the-art Compton gamma-ray source, High Intensity Gamma-Ray Source (HIGS). To produce FEL lasing below 190 nm and gamma-ray beams above 100 MeV, the FEL system needs to be upgraded by adding two helical OK-5 wigglers to increase the FEL gain with four OK5 wigglers for the VUV operation. To simultaneously preserve the linear polarization capability of the gamma-ray beam produced by the planar OK-4 FEL, a wiggler switchyard system is under development which will enable the switch between two planar OK-4 wigglers and two helical OK-5 wigglers in the middle of the FEL straight. In this work, we present the new magnetic lattice designed for the operation of the wiggler switchyard system. This new lattice is developed with great flexibility for the operation with different numbers of FEL wigglers, variable betatron tunes, and adjustable electron beam sizes at the collision point for the HIGS. In addition, the new lattice is developed for the operation in a wide range of energies, from 280 MeV to 1.2 GeV, with proper nonlinear dynamics compensations in order to realize a large dynamic aperture.

TUPPC070

Alternating Spin Aberration Electrostatic Lattice for EDM Ring

lattice, simulation, quadrupole, proton

1332

Y. Senichev, R. Maier, D. Zyuzin
FZJ, Jülich, Germany
M. Berz
MSU, East Lansing, Michigan, USA

The idea of the electric dipole moment search using the storage ring (SrEDM) with polarized beam is realized under condition of the long-time spin coherency of all particles, the time during which the RMS spread of the spin orientation of all particles in the bunch reaches one radian. Following the requirements of the planned EDM experiment, the SCT should be more than 1000 seconds. During this time each particle performs about 10⁹ turns in the storage ring moving on different trajectories through the optics elements. At such conditions the spin-rotation aberrations associated with various types of space and time dependent nonlinearities start to play a crucial role. In this paper we consider a new method based on the alternating spin drift, causing it to rotate alternately, thereby limiting the growth of aberrations at one order of magnitude lower. As a result, using this method we can achieve the SCT of the order of 5000-6000 seconds. The difficulties of these studies are still in the fact that the aberrations growth observed in the scale of a 10⁹ turns. For the study we use an analytical method in composition with a numerical simulation by COSY Infinity.

TUPPC074

Study of Resonance Driving Term in Electron Storage Rings

damping, radiation, resonance, electron

1344

G. Liu, W. Li, L. Wang
USTC/NSRL, Hefei, Anhui, People's Republic of China

The resonance driving term (RDT) is useful to analyze and optimize the nonlinear performance of the storage ring. In addition to analytical calculation of RDT, experimental measurement of RDT has been made in some proton storage rings based on turn-by-turn BPM data. For electron storage rings, the analysis is more complicated due to decoherence effects and strong radiation damping. The relation between spectral decomposition of BPM data and RDT is derived and validated using beam numerical tracking data in this paper.

TUPPD005

Design Concept for Nu-STORM: an Initial “Very Low-Energy Neutrino Factory”

injection, target, proton, factory

1413

D.V. Neuffer, A.D. Bross, S. Geer, A. Liu, M. Popovic
Fermilab, Batavia, USA
C.M. Ankenbrandt, T.J. Roberts
Muons, Inc, Batavia, USA

Funding: US DOE under contract DE-AC02-07CH11359
We present a design concept for a Nu-source from a STORage ring for Muons - NuSTORM. In this initial design a high-intensity proton beam produces ~5 GeV pions that provide muons that are captured using “stochastic injection” within a ~3.6 GeV racetrack storage ring. In “stochastic injection”, the ~53 GeV pion beam is transported from the target into the storage ring, dispersion-matched into a long straight section. (Circulating and injection orbits are separated by momentum.) Decays within that straight section provide muons that are within the ~2 GeV/c ring momentum acceptance and are stored for the muon lifetime of ~1000 turns. Muon (and pion) decays in the long straight sections provide neutrino beams that can be used for precision measurements of neutrino interactions, and neutrino oscillations or disappearance at L/E=~1 m/MeV. The facility is described and variations are discussed.

TUPPD043

Resonant Reaction with a Superintense Circulating Beam

target, proton, electron, resonance

1497

V.G. Dudnikov, C.M. Ankenbrandt
Muons, Inc, Batavia, USA

A system for efficient generation of resonance reaction in the interaction of the circulating ion beam with a thin internal target is considered. Features of this system are high intense space charge compensated circulating ion beam with an intensity greater then a space charge limit in a near integrable nonlinear focusing system. Ionization energy loss is compensated by inductive electric field. Multiple scattering and energy straggling are compensated by electron cooling with a tabular electron beam. In this method it is possible to compensate an energy loss of circulating particles after crossing the target and have a crossing of resonant energy in every passing of target. For sharp resonance reactions and monoenergetic beams a thin target method can increase greatly the energy efficiency.

TUPPP007

Modifications to the Machine Optics of BESSY II Necessitated by the EMIL Project

undulator, optics, cryogenics, dipole

1614

P.O. Schmid, J. Bahrdt, T. Birke, R. Follath, P. Kuske, D. Simmering, G. Wüstefeld
HZB, Berlin, Germany

The Helmholtz Zentrum Berlin and the Max Planck Society are going to build a new dedicated X-ray beam line at the synchrotron source light source BESSY II which will be used for analyzing materials for renewable energy generation. The new large scale project has been dubbed EMIL. In this document we present the modifications to the machine optics and to what extent these changes affect the performance of BESSY II.

TUPPP010

Spectral and Temporal Observations of CSR at ANKA

radiation, synchrotron, optics, synchrotron-radiation

1623

V. Judin, N. Hiller, A. Hofmann, E. Huttel, B. Kehrer, M. Klein, S. Marsching, C.A.J. Meuter, A.-S. Müller, M. Schuh, M. Schwarz, N.J. Smale, M. Streichert
KIT, Karlsruhe, Germany
M.J. Nasse
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany

Funding: This work has been supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320.
ANKA is a synchrotron light source situated at the Karlsruhe Institute of Technology. Using dedicated low-α-optics at ANKA we can reduce the bunch length and generate Coherent Synchrotron Radiation (CSR). Studies of the coherent emission in the time domain allow us to gain an insight into the longitudinal bunch dynamics. These as well as the systematic investigations of the THz spectrum range can be used for benchmarking of theoretical predictions. In this paper we report about the recent progress in CSR observation using fast THz detectors and a Martin-Puplett spectrometer at the ANKA storage ring.

TUPPP011

Simulations of Fringe Fields and Multipoles for the ANKA Storage Ring Bending Magnets

multipole, simulation, optics, sextupole

1626

M. Streichert, M.J. Nasse
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
V. Afonso Rodriguez, A. Bernhard, N. Hiller, E. Huttel, V. Judin, B. Kehrer, M. Klein, S. Marsching, C.A.J. Meuter, A.-S. Müller, M. Schwarz, N.J. Smale
KIT, Karlsruhe, Germany

Funding: This work has been supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320.
ANKA is the synchrotron light source of the Karlsruhe Institute of Technology (KIT). With a maximum particle energy of 2.5 GeV, the storage ring lattice consists of 16 bending magnets with a nominal magnetic flux density of 1.5 T. For the beam dynamics simulations the consideration of the fringe fields and multipoles is essential. A reference measurement of the longitudinal magnetic flux density profile of a bending magnet exists for a current of 650 A, corresponding to a particle energy of 2.46 GeV. For lower beam energies where the magnets are no longer close to saturation, however, the exact density profiles may vary significantly. In order to derive fringe fields and multipole components for different beam energies, simulations of the magnetic flux density for different beam energies were conducted using a finite element method (FEM). We present the results of the simulations and demonstrate the improvements of the beam dynamics simulations in AT (Accelerator Toolbox).

TUPPP015

Status and Recent Progress of SPring-8

coupling, emittance, lattice, optics

1638

H. Ohkuma
JASRI/SPring-8, Hyogo-ken, Japan

The SPring-8 is an 8 GeV synchrotron radiation facility that has been in operation since 1997. The SPring-8 has been operated well and total user time has reached more than 53,700 hours, 75% of the total operation time. The average user time per year is about 4,000 hours. The average availability is about 98% in the past 15 years. The operational status and recent progress overview of SPring-8 is presented: the local lattice modification of 30-m long straight section for installing small gap (min. gap is 5.2 mm) in-vacuum undulators, the emittance coupling correction for the vertical beam size reduction, the test operation of low energy operation for the energy saving, and the study of lower emittance optics for the present SPring-8 storage ring. An outline of a future upgrade with a full-scale major lattice modification is also presented. We also present a little about recent progress of SPring-8 injecting accelerators.

TUPPP018

Design and Commissioning of the Very Low Emittance Optics in the SSRF Storage Ring

emittance, optics, injection, lattice

1647

S.Q. Tian, J. Chen, B.C. Jiang, Y.B. Leng, H.H. Li, L.Y. Yu, M.Z. Zhang, W.Z. Zhang, Z.T. Zhao
SINAP, Shanghai, People's Republic of China

In synchrotron radiation light sources, there are continuous efforts to lower the storage ring emittance and thus increase its photon beam brightness. The lowest effective emittance of SSRF is found by a systematic method. Results of design and commissioning of this kind of optics are presented, of which the beam emittance is smaller than the nominal one by 1 nm.rad. The measured beam parameters agree well with the design ones.

TUPPP019

Overview of the Solaris Facility

linac, klystron, dipole, vacuum

1650

C.J. Bocchetta, M. Bartosik, P.P. Goryl, K. Królas, M. Młynarczyk, W. Soroka, M.J. Stankiewicz, P.S. Tracz, Ł. Walczak, A.I. Wawrzyniak, K. Wawrzyniak, J.J. Wiechecki, M. Zając, L. Zytniak
Solaris, Kraków, Poland
R. Nietubyć
The Andrzej Soltan Institute for Nuclear Studies, Centre Świerk, Świerk/Otwock, Poland

Funding: Work supported by the European Regional Development Fund within the frame of the Innovative Economy Operational Program: POIG.02.01.00-12-213/09
The Polish synchrotron light source Solaris is under construction in Kraków. The project is based on the MAX IV light source being built in Lund, Sweden. The 1.5 GeV storage ring for Solaris and part of the injector complex are identical to that of MAX IV, although both are housed in buildings that differ from those of MAX IV. Ground breaking on the green field site at the Jagiellonian University campus occurred at the start of 2012. A detail description of the facility infrastructure, services and construction choices is given together with the latest project developments for main accelerator systems.

TUPPP022

Beam Optics Measurements during ALBA Commissioning

quadrupole, lattice, optics, emittance

1656

M. Muñoz, G. Benedetti, J. Campmany, D. Einfeld, Z. Martí
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

The synchrotron light source ALBA is in the final stage of the Storage Ring commissioning, with the beamline commissioning well under way. This paper reviews the results of the modeling of the lattice and the agreement with the LOCO measurement of the machine; the performance of the beta beating correction (critical in the ALBA case due to the large gradient in the bending magnet and the low number of quadrupole families), including effect of insertion devices; the lifetime measurement; tune scans; tune shift with horizontal amplitude; and the general agreement of the machine to the model using during the design. A brief summary of the modeling of the injector chain is included.

TUPPP023

Operation Status of ALBA Synchrotron Light Source

feedback, vacuum, emittance, kicker

1659

M. Pont
CELLS-ALBA Synchrotron, Cerdanyola del Vallès, Spain

ALBA is a 3.0 GeV third generation synchrotron light source which has been commissioned during 2011. From October 2011 up to 7 beamlines are delivering beam for beamline commissioning, 6 from insertion devices and 1 from a bending magnet. Since April 2012 the facility is open to external users. Beam current has been continuously increased and the present stored beam current for users is 200 mA in a multi-bunch filling pattern. Orbit stability is kept at ±1 micron with a slow orbit feedback. The paper will review the operation and performance status of the different subsystems and review also the main objectives for 2012: target current of 400 mA, delivery of 3000 hours of beam to beamlines, testing of a fast orbit feedback system as well as preparations for top-up operation.

TUPPP024

Recent Progress on the MAX IV 1.5 GeV Storage Ring Lattice and Optics

lattice, dipole, vacuum, sextupole

1662

S.C. Leemann
MAX-lab, Lund, Sweden

Construction of the MAX IV facility started in 2010 and commissioning is expected to begin in 2014. Once completed, the facility will include two storage rings for the production of synchrotron radiation. The 3 GeV ring will house insertion devices for the production of x-rays, while the 1.5 GeV ring will serve UV and IR users. Recently, the lattice and optics of the 1.5 GeV storage ring have been modified as a result of detailed magnet and vacuum system design. This paper discusses the lattice and optics changes as well as their effects.

TUPPP025

Resurrection of RESOLVE at NSRRC Prepared for the First Turn Beam Steering of the TPS Commissioning

injection, controls, quadrupole, kicker

1665

H.-P. Chang, H.H. Chen, P.C. Chiu, P.J. Chou, K.T. Hsu, S.J. Huang, Y.-C. Liu, F.H. Tseng
NSRRC, Hsinchu, Taiwan

MATLAB based high level application software prepared for the 3GeV Taiwan Photon Source has been built and tested on the 1.5GeV Taiwan Light Source continuously. The RESOLVE program is surveyed and resurrected at NSRRC to support and help the first turn beam steering in the coming commissioning of the TPS accelerator complex. Due to the RESOLVE’s history, it contributed a lot in the past commissioning of SLC at SLAC National Accelerator Laboratory, we believe it may give help although most of the first turn beam steering of current light source machines may pass smoothly with well machine construction. In order to make the revised RESOLVE working, not only the compiling problem but also some memory bugs have been fixed, the updated RESOLVE now can be run on PC/Linux and Mac/OSX computer systems. We are trying to apply and test it on the TLS SR with the turn-by-turn digital BPM system. Some exercises of the error finding in beam steering of the off-axis injection beam are performed for presentation.

TUPPP028

A Study of Girder Alignment with Survey Measurements In the Diamond Storage Ring

survey, closed-orbit, sextupole, insertion

1674

M. Apollonio, R. Bartolini, R.T. Fielder, W.J. Hoffman, J. Kay, I.P.S. Martin, B. Singh
Diamond, Oxfordshire, United Kingdom

Using a model of the Diamond storage ring which includes displacements and rotations of the 74 magnet girders an attempt has been made to correlate survey data with the corrector magnet (CM) strengths required for a zero orbit. We then use the model to deduce the most effective girder movements that will bring about a reduction in corrector strength. We describe the results of these studies, and suggest a test with a deliberately displaced girder and the effect on corrector strengths, aimed at enhancing our understanding of the system

TUPPP032

Use of Multi-objective Methods for Choosing Undulators for Storage Rings

brightness, photon, undulator, target

1680

M. Borland
ANL, Argonne, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
Users of storage ring light sources generally rely on undulators to provide the highest brightness. Choice of the optimal undulator period is complicated by the fact that users do not operate at a single photon energy or place equal weight on operation at all photon energies of interest. In addition, some users may be best served by a double- or triple-period revolver device. In this paper, we present a method of narrowing the choice of undulator periods based on multi-objective techniques. Applications are shown in the context of the Advanced Photon Source Upgrade.

TUPPP033

Exploration of a Tevatron-sized Ultimate Storage Ring

emittance, brightness, damping, sextupole

1683

M. Borland
ANL, Argonne, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
With the Tevatron now shut down and slated for decommissioning, it is only natural to think about other possible uses for the 6.3 km tunnel. Given that the brightness of electron storage rings naively scales as radius cubed, one exciting possibility is to build a so-called ultimate storage ring light source. This paper describes a somewhat speculative exploration of this idea, showing the potential for a storage ring x-ray source of unprecedented brightness.

TUPPP042

Passive Landau Cavity Effects in the NSLS-II Storage Ring

cavity, simulation, impedance, wakefield

1701

G. Bassi, A. Blednykh, S. Krinsky
BNL, Upton, Long Island, New York, USA

Funding: Work supported by DOE contract No: DE-AC02-98CH10886.
In new 3rd generation synchrotron light sources with small transverse emittance, higher harmonic cavities (Landau cavities) are installed for bunch lengthening to increase the Touschek lifetime, and to provide Landau damping for beam stability. In this contribution we study the effects of passive Landau cavities in the NSLS-II storage ring for arbitrary fill-patterns with the OASIS tracking code.

TUPPR057

Intrabeam Scattering Studies at the Swiss Light Source

emittance, damping, scattering, monitoring

1951

F. Antoniou, Y. Papaphilippou
CERN, Geneva, Switzerland
M. Aiba, M. Böge, N. Milas, A. Streun
Paul Scherrer Institut, Villigen, Switzerland
T. Demma
INFN/LNF, Frascati (Roma), Italy

The target parameters of modern ultra-low emittance rings are entering into a regime where intra-beam scattering (IBS) becomes important and, in the case of linear collider damping rings, even a limitation for the delivered emittances. The Swiss Light Source (SLS) storage ring, as it has achieved a vertical geometrical emittance of around 2 pm at 2.4 GeV, and it has the ability to run at even lower energies, and the availability of emittance monitoring diagnostics, is an ideal test bed for IBS studies. Simulations using the classical IBS theories and tracking codes are undertaken in order to explore the possibilities and limitations for IBS measurements at the SLS. In this respect, comparison between the theories and codes is first discussed. The dependence of the output emittances, taking into account the effect of IBS, with respect to energy, bunch charge and zero current vertical and longitudinal emittance is also studied, in order to define the regimes where the IBS effect can be significant. First measurement results from the SLS running at lower energies are finally presented.

WEOAA01

Injected Beam Imaging at SPEAR 3 with a Digital Optic Mask

injection, synchrotron, target, quadrupole

2116

H.D. Zhang, R.B. Fiorito, A.G. Shkvarunets
UMD, College Park, Maryland, USA
W.J. Corbett, A.S. Fisher, K. Tian
SLAC, Menlo Park, California, USA

Funding: *This work is partially funded by the Office of Naval Research and the DOD Joint Technology Office.
At SPEAR3, the light source operates in top-up injection mode with 273nC charge circulating in the storage ring (350mA). Each individual injection pulse contains only 40pC, or a contrast ration of 1:6800. In order to monitor injected beam dynamics during User operations, it is desirable to optically image the injected charge distribution on a turn-by-turn basis in the presence of the bright stored beam. The measurement is made by re-imaging visible synchrotron radiation onto a 1024x768 pixel Digital-Micro-Array mirror device (DMD) which is used to 'mask' light from the central stored beam while observing the weak injected beam signal on an intensified, fast-gated CCD camera. Complex beam dynamics are observed after only a few 10's of turns around the synchrotron. In this paper we report on the DMD optical configuration, masking considerations, measurement timing and initial tests imaging the injected beam in the presence of stored beam.

Slides WEOAA01 [1.874 MB]

WEPPD010

Re-commissioning of the ESRF Storage Ring Vacuum System

vacuum, synchrotron, insertion, insertion-device

2516

M. Hahn, I. Parat
ESRF, Grenoble, France

A long shutdown of the accelerators to allow the construction of new buildings marked the phase one of the ESRF upgrade program. A number of vacuum sectors has been modified during this time for repair and maintenance but mainly to increase the brilliance of the synchrotron radiation beams by installing longer insertion device (ID) vessels with non-evaporable getter (NEG) coating and a new In Vacuum Undulator. The paper gives an overview of the modified machine and reports experience with its re-conditioning.

WEPPD022

Design of the Water-Cooling System for the Vacuum System of the TPS Storage Ring

vacuum, synchrotron, photon, controls

2546

Y.C. Yang, C.K. Chan, J.-R. Chen, C.M. Cheng, G.-Y. Hsiung
NSRRC, Hsinchu, Taiwan

Taiwan Photon Source (TPS) was under construction since 2009. TPS vacuum system was designed in 10^-10 torr level and gas load from synchrotron light was almost confined in bending chambers. A water cooling system was designed to protect vacuum equipment including vacuum chambers and absorbers to avoid melting down by synchrotron light. There are 3 cooling loops for aluminum chambers and 4 loops for cooper absorbers in one unit cell. One prototype for unit cell, including arrangement of control terminal, monitor of flow rate and temperature, and vibration from cooling system will be tested.

WEPPD026

Design and Fabrication of NSLS-II Storage Ring Vacuum Chambers and Components

vacuum, photon, multipole, impedance

2558

H.-C. Hseuh, A.T. Anderson, L. Doom, M.J. Ferreira, C. Hetzel, C. Longo, V. Ravindranath, K. Roy, S.K. Sharma, J.L. Tuozzolo, K. Wilson
BNL, Upton, Long Island, New York, USA

Funding: Work performed under the auspices of U.S. Department of Energy, under contract DE-AC02-98CH10886
The National Synchrotron Light Source II, a 3-GeV, 792-meter circumference, synchrotron radiation facility with ultra-high-flux and brightness, is under construction at Brookhaven National Laboratory. The storage ring vacuum chambers are mainly made of extruded aluminium but with a few made of stainless steel and inconel. The synchrotron radiation from bending magnets is intercepted at discrete photon absorbers made of GlidCop. NEG strips in the ante-chamber provide the distributed pumping, while lumped ion pumps and titanium sublimation pumps at photon absorbers remove the desorbed gas. The complex vacuum system is being assembled and integrated in-house. This paper describes the design and fabrication of both standard and special vacuum chambers, the low impedance RF shielded bellows and the photon absorbers. The vacuum system is now moving into the conditioning, installation and testing phase. Details and experience from the large scale production, testing and lesson learned will also be presented.

WEPPD039

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

status, booster, controls, power-supply

2597

J.-C. Chang, W.S. Chan, J.-R. Chen, Y.F. Chiu, Y.-C. Chung, K.C. Kuo, Y.-C. Lin, C.Y. Liu, I. 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 will be completed in the end of 2011. The whole construction of the utility system is scheduled to be completed in the end of 2012. 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.

WEPPD045

An Application of Multi-stage Adjustable Shock Absorbers for the Girders of Storage Ring in Taiwan Photon Source

damping, acceleration, controls, photon

2615

C.-S. Lin, J.-R. Chen, M.L. Chen, H.C. Ho, K.H. Hsu, D.-G. Huang, C.K. Kuan, W.Y. Lai, C.J. Lin, H.M. Luo, S.Y. Perng, P.L. Sung, Y.L. Tsai, T.C. Tseng, H.S. Wang, M.H. Wu
NSRRC, Hsinchu, Taiwan
D.-Y. Chiang
NCKU, Tainan city, Taiwan

Beam stability is a major concern for the operation of the Taiwan Photon Source (TPS). One of the many factors to instability of electron beam is mechanical vibration of the accelerator components. The TPS uses steel girders to support the magnets and vacuum chambers in the storage ring. Three pedestal and six mover assemblies support the girders. Multi-stage adjustable shock absorbers are designed for passive vibration damping, and presently installed between the girders and the pedestals. Through adjusting the amount of hydraulic fluid which bypasses the damping passage between two hydraulic chambers, the desired damping coefficient of the damping absorbers can be achieved. Experimental results of modal testing presented in this paper show that the multi-stage adjustable damping absorbers under the assembly of the girders reduced the level of girder vibration.

WEPPD046

Design of Machine Protection System for the Taiwan Photon Source

EPICS, controls, vacuum, status

2618

C.Y. Liao, J. Chen, Y.-S. Cheng, K.T. Hsu, K.H. Hu, C.H. Kuo, D. Lee, C.Y. Wu
NSRRC, Hsinchu, Taiwan

The Taiwan Photon Source (TPS) is being constructed at the campus of the NSRRC (National Synchrotron Radiation Research Center). In order to prevent damage to accelerator components induced by various events, design of the global machine protection system (MPS) is on-going. The MPS collect interlock and beam dump request from various system, perform decision, transmit dump beam request to RF system. The PLC based system will be used as a slow MPS which can delivery less than 8 msec reaction time. The fast MPS will dependent on event based timing system to deliver response time less than 5 μsec. Trigger signal for post-mortem will also be distributed by the fast MPS. To ensure alive of the system, several self-diagnostics mechanisms include heartbeat and transient capture will be implemented. The MPS architecture, plans and implementation were presented in this report.

WEPPP018

A New Beam Injection Scheme for a Compact Low-energy Storage Ring

injection, kicker, damping, acceleration

2761

Y. Honda
KEK, Ibaraki, Japan

A very compact storage ring at low energy has an unique application such as Compton X-ray source. Scheme for efficient injection is an issue for such a compact storage ring. Utilizing a phase-shift in the non-relativistic energy region, a new idea for accumulating the incoming bunch on an already circulating bunch without any kicker or orbit bump has been presented. Its applicable parameter range will be presented.

WEPPP057

Orbit Correction Studies using Neural Networks

controls, simulation, target, synchrotron

2837

E. Meier, G. LeBlanc, Y.E. Tan
ASCo, Clayton, Victoria, Australia

This paper reports the use of Neural Networks for orbit correction at the Australian Synchrotron Storage Ring. The proposed system uses two Neural Networks in an actor-critic scheme to model a long term cost function and compute appropriate corrections. The system is entirely based on the history of the beam position and the actuators, the corrector magnets, in the storage ring. This makes the system auto-tuneable, which has the advantage of avoiding the use of a response matrix. As a generic and robust orbit correction program it can be used during commissioning and in slow orbit feedback. In this study, we present positive initial results of the simulations of the storage ring in Matlab. We will also discuss the possibility of reconstructing the response matrix from the information stored in the neural network for offline orbit response matrix analysis.

WEPPP062

Characterization and Stabilization of Multi-Bunch Instabilities at the ANKA Storage Ring

feedback, kicker, injection, controls

2849

E. Huttel
FZK, Karlsruhe, Germany
N. Hiller, E. Huttel, V. Judin, B. Kehrer, S. Marsching, A.-S. Müller, N.J. Smale
KIT, Karlsruhe, Germany

ANKA is a 2.5 GeV storage ring for synchrotron radiation. Up to 200 mA are accumulated at 0.5 GeV and then ramped to 2.5 GeV. In the past storage ring operation suffered from vertical multi-bunch instabilities. These could partially be cured by increased chromaticity, a large gap in the filling structure and by keeping the beam longitudinally unstable. A vertical digital bunch-by-bunch system from ITECH has been installed that allows an operation of the storage ring without exciting the longitudinal modes. In addition, the system allows analyzing multi-bunch instabilities both transverse and longitudinal and their dependence from cavity temperature, filling structure and chromaticity. This paper reports on our experience operating this system and presents an investigation of multi-bunch modes in the ANKA storage ring.

WEPPP064

Design and Simulation of the Stripline Transverse Quadrupole Kicker for HLS II

quadrupole, kicker, impedance, dipole

2852

F.F. Wu, W.B. Li, P. Lu, T.J. Ma, B.G. Sun, Y.Y. Xiao, H. Xu, Y.L. Yang, Z.R. Zhou
USTC/NSRL, Hefei, Anhui, People's Republic of China

In order to investigate the possibility of excite a transverse quadrupole mode oscillation of the electron bunch in the HLS II storage ring, we design a stripline transverse quadrupole kicker. The characteristic impedance of some modes(dipole modes, sum mode, quadrupole mode) of the optimised stripline kicker must match 50Ω characteristic impedance of the external transmission lines so as to reduce the reflected power. We use nonlinear least square method to optimise the kicker and compare characteristic impedances of calculation using 2D Possion code and fitted function of several variables, then we get optimised size with integrated use of Possion code and fitted function of several variables. Using the 2D Poisson code, we simulate the electric field distribution of dipole modes when the horizontal or the vertical electrodes are at opposite unit potentials, and the electric field distribution of quadrupole mode using quadrupole kick. We verified that the designed stripline kicker can excite a transverse quadrupole mode oscillation of the electron bunch.

WEPPP065

Status of the SSRF Fast Orbit Feedback System

feedback, controls, electron, insertion

2855

B.C. Jiang, J. Hou, C.X. Yin, Z.T. Zhao
SINAP, Shanghai, People's Republic of China

The fast orbit feedback system with bandwidth up to 100Hz is under commissioning at SSRF. The main purposes of the system are to suppress the short term orbit stability under sub-micron level and to compensate the orbit distortions caused by changing gaps of the insertion devices. The layout of the system is described and the preliminary commissioning results are given out in this paper.

WEPPP067

Commissioning Results of Slow Orbit Feedback using PID Controller Method for the Siam Photon Source

feedback, controls, photon, LabView

2861

S. Klinkhieo, S. Boonsuya, P. Klysubun, S. Krainara, P. Songsiriritthigul, P. Sudmuang, N. Suradet
SLRI, Nakhon Ratchasima, Thailand
S. Rujirawat
Suranaree University of Technology, Nakhon Ratchasima, Thailand

A slow orbit feedback (SOFB) system has been developed to improve the orbit stability for the storage ring of the Siam Photon Source (SPS). The SOFB uses a PID controller method utilizing LabVIEW channel to access 20 BPMs and 28 correctors of the storage ring. The first phase implementation of the feedback loops based on this method was operated at 0.05Hz of sampling frequency, which reduce the fluctuation of both horizontal and vertical positions of the orbit from ~200 microns down to ~30 microns. The commissioning results indicate that further work and hardware upgrade are required. A higher sampling frequency at least 30Hz is strongly required for PID controller implementation. Upgrading of the existing 12-bit resolution corrector power supplies is also necessary. The basic principle of PID algorithms, hardware, software and commissioning results of the current SOBF system, as well as a future development plan, will be presented.

WEPPP069

Performance Enhancements for the Transverse Feedback System at the Advanced Photon Source

feedback, EPICS, photon, controls

2867

N.P. Di Monte, R.I. Farnsworth, A.J. Scaminaci
ANL, Argonne, USA

With the success of the transverse feedback system at the Advanced Photon Source (APS), an upgrade to this system is being developed. The current system is operating at a third of the storage ring bunch capacity, or 324 of the available 1296 bunches. This upgrade will allow the sampling of all 1296 bunches and make corrections for all selected bunches in a single storage ring turn. To facilitate this upgrade, a new analog I/O board capable of 352-MHz operation is being developed along with a P0 bunch cleaning circuit. The clock cleaning circuit is also needed for the high speed analog output circuit, which is transmitted about 200 m to a separate DAC unit in real time. This remote DAC will have its transceiver data rate triple from 2.3 Gb to about 7 Gb on a fiber optic link. This paper will discuss some of the challenges in reducing the clock jitter from the system P0 bunch clock along with the necessary FPGA hardware upgrades and algorithm changes, all of which are required for the success of this upgrade.

WEPPP070

Simulation of the APS Storage Ring Orbit Real-Time Feedback System Upgrade Using MATLAB

feedback, simulation, controls, dipole

2870

S. Xu, G. Decker, R.I. Farnsworth, F. Lenkszus, H. Shang, X. Sun
ANL, Argonne, USA

Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
The Advanced Photon Source (APS) storage ring orbit real-time feedback (RTFB) system plays an important role in stabilizing the orbit of the stored beam. An upgrade is planned that will improve beam stability by increasing the correction bandwidth to 200 Hz or higher. To achieve this, the number of available steering correctors and beam position monitors (BPMs) will be increased, and the sample rate will be increased by an order of magnitude. An additional benefit will be the replacement of aging components. Simulations have been performed to quantify the effects of different system configurations on performance.

WEPPP071

Phase Noise Studies at the Advanced Photon Source

simulation, synchrotron, feedback, photon

2873

N. Sereno, G. Decker, R.M. Lill, B.X. Yang
ANL, Argonne, USA

Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
Phase noise generated primarily by power line harmonics modulating the 352-MHz rf system in the APS storage ring is a dominant source of high- frequency beam motion, both longitudinally and transversely, due to dispersion in the lattice. It also places fundamental limits on the ability to generate picosecond-scale x-ray pulses for fast pump / probe experiments*. Measurements using turn-by-turn beam position monitors (BPMs) located at high-dispersion locations are compared and contrasted with results from a dedicated S-band phase detector connected to either a capacitive pickup electrode or a diamond x-ray detector. Horizontal beam position at high-dispersion locations is related directly to beam phase by a very simple relation involving the momentum compaction. Simulation results are used to validate this relationship and to quantify the relation between phase noise on the main rf vs beam arrival time jitter.
* A. Zholents et al., NIM A 425, 385 (1999).

WEPPP088

Auto-alignment System and CalibrationPprocedure in TPS Girder System

alignment, laser, survey, photon

2918

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

The TPS (Taiwan photon source) project is under construction and will be finished in the December 2012. Considering the floor’s deformation with time and frequent earthquakes at Taiwan, the survey and alignment procedure should be taken quite often. For dealing with these difficulties and improving accuracy of girder’s position, a highly accurate auto-tuning girders system was designed to accomplish the alignment tasks. There are two cells of TPS girders and varied sensor modulus set up for testing the auto-tuning system. The adjustment of the system converges to less than 6um, and the repeatability of the testing is under 10 um. For improving the accuracy of girders position, that is critical thing to make sure all the calibration of sensors modulus correctly and accurately. The calibration procedure about sensor modular and testing results is described in this paper.

WEPPP089

Study of the Combined Controller for Adjusting and Locking a Girder with Micrometer-level at NSRRC

controls, monitoring, feedback, synchrotron

2921

H.S. Wang, M.L. Chen, W.Y. Lai, S.Y. Perng, Y.L. Tsai, T.C. Tseng
NSRRC, Hsinchu, Taiwan
J.-R. Chen
NTHU, Hsinchu, Taiwan

A girder control system is proposed to quickly and precisely adjust the displacement and rotating angle of all girders in the storage ring with little manpower at the Taiwan Photon Source (TPS) project at National Synchrotron Research Center (NSRRC). In this control girder system, six motorized cam movers supporting a girder are driven on three pedestals to perform six-axis adjustments of a girder. To increase the nature frequency of a girder, the locking system is applied to promote the stiffness of a girder structure. The locking system consists of six locking mechanisms attached to three inboard pedestals and a locking controller. The study of the girder control system and the locking system control combined are achieving to the positioning with micrometre-level. This paper presents details of the study and tests of the combined controller.

WEPPR014

Recovering Measured Dynamics from a DC Circulating Space-Charge-Dominated Storage Ring

electron, background, space-charge, diagnostics

2967

W.D. Stem, B.L. Beaudoin, I. Haber, T.W. Koeth
UMD, College Park, Maryland, USA

Funding: This work is supported by the US Dept. of Energy Offices of High Energy Physics and Fusion Energy Sciences, and by the US Dept. of Defense Office of Naval Research and Joint Technology Office.
Space-charge is increasingly significant at high beam intensities such as in FEL injectors and heavy ion inertial fusion drivers, where it dominates the beam dynamics. The University of Maryland Electron Ring (UMER) is a high intensity circular machine that is dedicated to the study of long path length space-charge-dominated beam physics on a small scale. Over multiple turns, longitudinal space charge effects cause the tail and head of an electron bunch to expand and interpenetrate, eventually resulting in a “DC beam”. This leads to complications when trying to measure the beam with UMER’s AC coupled diagnostics. Three techniques are developed to recover the information within the beam. Two “knockout” techniques implement invasive pulsed electric kicks to the beam in combination with either a fluorescent imaging screen or a current monitor. A third technique based on integration of the wall-current signal provides a non-invasive method to study the DC beam dynamics. Experimental results from all three methods are compared. The DC beam profile can then be studied over long trajectories and the existence of any loss mechanisms can be determined.

WEPPR046

THz Bursting Thresholds Measured at the Metrology Light Source

electron, synchrotron, vacuum, octupole

3030

M. Ries, J. Feikes, P.O. Schmid, G. Wüstefeld
HZB, Berlin, Germany
A. Hoehl
PTB, Berlin, Germany

At the Metrology Light Source (MLS) * of the Physikalisch-Technische Bundesanstalt (PTB) the bunch length can be varied by more than two orders of magnitude **. The bunch length manipulation is achieved by varying different machine parameters, such as rf-voltage amplitude up to 500 kV and the momentum compaction factor over three orders of magnitude. The subject of this article is the measurement of THz bursting thresholds at the MLS for different bunch lengths.
* B. Beckhoff et al., Phys. Status Solidi B 246, p. 1415 (2009)
** J. Feikes et al., Phys. Rev. ST Accel. Beams 14, 030705 (2011).

WEPPR057

On the Single Bunch Longitudinal Collective Effects in BEPCII

impedance, electron, collective-effects, controls

3054

D. Wang, Z. Duan, J. Gao, Y. Li, L. Wang, L. Wang, N. Wang
IHEP, Beijing, People's Republic of China

Funding: National Natural Science Foundation of China,project 11175192.
In order to study the single bunch longitudinal instability in BEPCII, experiments on the bunch lengthening phenomenon were made. By analyzing the experimental data based on the Gao’s theory, the longitudinal loss factor for the bunch are obtained. Also, the total wake potential and the inductance of the machine are estimated.

WEPPR059

The Simulation of Ion Cloud Build-up in Electron Storage Ring

ion, electron, simulation, space-charge

3060

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

In electron storage rings, positive ions are created by the ionization of the residual gas. Three main collision types including elastic collision, excitation collision and ionization collision are considered in this paper. In order to calculate the probability of the gas ionization using DSMC method, the total cross section, total inelastic cross section, elastic cross section, excitation cross section and ionization cross section are deduced separately. Once ions are created，PIC is adopted to trace the ion，s motion under the combined action due to externally applied field and self-field. The purpose of all study is to present how ion cloud gets to equilibrium little by little.

WEPPR079

Observations of Microbunching Instabilities from a THz Port at Diamond Light Source

radiation, synchrotron, optics, electron

3114

W. Shields, G.E. Boorman, V. Karataev, A. Lyapin
JAI, Egham, Surrey, United Kingdom
R. Bartolini, A.F.D. Morgan, G. Rehm
Diamond, Oxfordshire, United Kingdom

Diamond Light source is a third generation synchrotron facility dedicated to producing radiation of outstanding brightness. Above a threshold current, the electron bunches are susceptible to the phenomenon known as the microbunching instability. This instability is characterised by the onset of radiation bursts, the wavelength of which is around one order of magnitude shorter than the bunch length. Near threshold, the bursting occurs quasi-‐periodically, however at higher currents, the bursting appears randomly. The high frequencies involved in these emissions make detection and analysis challenging. A port specifically for the investigation of mm wave emissions has recently been built at Diamond. Ultra fast Schottky Barrier Diode detectors have been installed to obtain data for only a small fraction of the bunch revolution time in an updated data acquisition system. The threshold current and subsequent evolution of the instability have been investigated.

WEPPR082

The Collective Effects of Long Straight Sections (LSSs) in the Advanced Photon Source Upgrade

impedance, undulator, collective-effects, injection

3120

Y.-C. Chae, L.H. Morrison
ANL, Argonne, USA

Funding: Work supported by U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under contract No. DE-AC02-06CH11357.
The Advanced Photon Source is a 7-GeV hard x-ray synchrotron light source. The APS Upgrade specifies additional beamlines delivering higher brightness and flux as well as for the short-pulse x-ray (SPX). In order to fulfill these demands we plan to provide long straight sections (LSS), for which the total length of the insertion devices is increased to 7.7m. The long straight section also helps in implementing the SPX scheme without removing insertion devices. However, the impedance of the LSS may reduce the single-bunch current of 16 mA per bunch delivered to the users during hybrid fill. We estimate the effect of LSS impedance on the bunched beam current and propose an impedance optimization of the undulator chamber with a small gap.

WEPPR083

New Sector 37 Chamber Design and Installation for High-Current Operation of the APS Storage Ring

impedance, vacuum, cavity, HOM

3123

Y.-C. Chae, R. Bechtold, W. Berg, L. Erwin, M. Givens, J.E. Hoyt, L.H. Morrison, K.M. Schroeder, R. Soliday, J.B. Stevens, G.J. Waldschmidt
ANL, Argonne, USA

Funding: Work supported by U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under contract No. DE-AC02-06CH11357.
The Advanced Photon Source is a 7-GeV hard x-ray synchrotron light source consisting of 40 sectors. Sector 37 accommodates four radio-frequency cavities followed by a short straight section, which is set aside for the future installation of a diagnostic device. The 60-cm-long section of spool pieces can be isolated by two gate valves and has an independent vacuum pump. The spool pieces are normally under high vacuum condition when the total current is below 100 mA. However, at the higher current required for the APS Upgrade, rf heating causes an unacceptable rise in temperature. We analyzed this situation by wakefield simulation, which led to a new chamber design. Proper fabrication and careful installation with twelve thermocouples ensured a temperature rise under 40-50 degrees Celsius at 100 mA. A brief thermal analysis shows that the present observed temperature rise in the new chamber is mainly due to the resistive wall.

WEPPR084

Measurement of Coherent Damping Rate of the APS Storage Ring

damping, feedback, kicker, pick-up

3126

C. Yao, K.C. Harkay, H. Shang, C.-X. Wang
ANL, Argonne, USA

Funding: Work supported by U.S. Department of Energy, Offices of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
The APS storage ring is a 7-GeV electron storage ring with a single-bunch current of up to 16 mA during normal user operations. To overcome beam instability we employ both chromatic correction and bunch-by- bunch feedback system. Typically we run a chromaticity of 4 for a 24-single fill pattern and 9 for a hybrids fill pattern in both planes with the feedback system loops closed. The APS upgrade (APS-U) calls for a beam current of 150 mA and installation of vertical deflecting cavities for short X-ray (SPX) production. In order to estimate whether the current chromatic correction and feedback system are adequate for the upgrade, we performed coherent damping rate measurements with two methods: kicking the beam with a kicker pulse and exciting the beam with the feedback system. We conclude that with a chromaticity of 4 in both planes, we can achieve a damping rate of 3 kHz in the x- plane and 2 kHz in the y-plane with feedback loops closed. Similar damping rates can also be achieved with chromatic correction alone. A special fitting program was developed to perform the damping rate analysis. This report presents the measurement data and results of the analysis.

WEPPR098

Two Dimensional Impedance Analysis of Segmented IVU

impedance, vacuum, undulator, simulation

3168

A. Blednykh, G. Bassi, J. Bengtsson, O.V. Chubar, C.A. Kitegi, T. Tanabe
BNL, Upton, Long Island, New York, USA

Funding: Work supported by DOE contract No: DE-AC02-98CH10886
Segmented Adaptive-Gap In-Vacuum Undulator (IVU) with variable magnetic gap along z-axis is considered as an alternative to the Constant Gap IVU (7mm gap) for the NSLS-II storage ring. The length of the Constant Gap IVU for a given minimum gap is limited by the beam stay clear aperture. With the new conceptual design of IVU the magnetic gap can be varied along z-axis and its minimum gap can be reduced down to 5.25mm in the center of the structure for the same stay clear aperture. Beam impedance becomes an important issue since the new design consists of several magnet gaps. Wakepotentials and impedances have been analyzed for a new type of IVU and the results compared with data for the reference geometry which is the Constant Gap IVU.

THXB03

Beam and Spin Dynamics in an Electric Proton EDM Ring

proton, lattice, dipole, quadrupole

3203

R.M. Talman
CLASSE, Ithaca, New York, USA
J. Talman
BNL, Upton, Long Island, New York, USA

Electric dipole moment (EDM) measurements may help to answer the question ‘‘Why is there more matter than anti-matter in the present universe?'' For a charged baryon like the proton such a measurement is thinkable only in a ring in which a bunch of protons is stored for more than a few minutes, with polarization ‘‘frozen'' (relative to the beam velocity) and with polarization not attenuated by decoherence. Beam and spin dynamics in an all-electric lattice with these characteristics is described. Rings for other charged baryons, such as deuterons or helium-3 nuclei, are also possible but, requiring both electric and magnetic fields, they are more complicated.

Slides THXB03 [0.155 MB]

THPPC003

Development of a Broad-band Magnetic Alloy Cavity at GSI

cavity, impedance, coupling, ion

3275

T.S. Mohite, U. Ratzinger
IAP, Frankfurt am Main, Germany
R. Balß, P. Hülsmann
GSI, Darmstadt, Germany

FINEMET, a Magnetic Alloy material, is often used to build a broad-band cavity for an accelerator or a storage ring. A research on the broad-band FINEMET cavity is of prime importance not only for the present accelerator facility but also for the future storage rings and synchrotron in upcoming FAIR facility alongside the GSI, Darmstadt. In several measurements, high intensity rare-isotope beams, with lower life time, are demanded at injection energy in Experimental Storage Ring (ESR) at GSI. A longitudinal beam stacking of such beams by means of using a special barrier-bucket RF cavity is found appropriate to serve this purpose*. Additionally, this cavity is supposed to provide the compressed bunches at lower energies for HITRAP, an ion-trap facility for experiments with highly charged ions, in FAIR. Several measurements are being performed, along with the theoretical analysis, to achieve the designed parameters for the planned barrier-bucket cavity. 60 FINEMET ring cores have been tested to confirm their designed electrical properties. Some of these ring cores are then loaded, in steps, in a test cavity, which will further be used as the barrier-bucket cavity for the ESR.
* C. Dimopoulou et al., JACoW Proceedings of COOL 2007, Bad Kreuznach, Germany

THPPC016

PLSII Linac RF Conditioning Status

linac, klystron, high-voltage, vacuum

3311

H.-S. Lee, J.Y. Huang, W.H. Hwang, H.-G. Kim, K.R. Kim, S.H. Kim, S.H. Kim, S.H. Nam, W. Namkung, S.S. Park, S.J. Park, Y.J. Park, S. Shin
PAL, Pohang, Kyungbuk, Republic of Korea

PLS linac has been upgraded in energy from 2.5 to 3.0 GeV. A klystron supplies RF power of 80 MW four acceleration structures through a SLED. But our machine is not enough RF power to get 3 GeV beam energy. So we have changed the RF scheme in four modules as a klystron supplies RF power of 80 MW two accelerating structures through a SLED. There were several problems during the RF conditioning and beam operation. So we will describe the conditioning results and the current status in this paper.

THPPC036

The Alpha Ferrite-loaded Coaxial Resonator Cavity

cavity, damping, resonance, radiation

3365

A.N. Pham, S.-Y. Lee, T.H. Luo
IUCEEM, Bloomington, Indiana, USA

Funding: Grant N00164-08-GM03 P00004 from the NSWC Crane Division, DOE Grant DE-FG02-92ER40747, and NSF Grant PHY-0852368 (IU: 48-432-31).
The Advanced Electron Photon Facility (ALPHA)*,** is a joint collaboration between the Indiana University Center for Exploration of Energy and Matter and the Crane Naval Surface Warfare Center. The ALPHA storage ring will serve as a debuncher in single pass mode of operation. With a set of two gradient damping wigglers, the storage ring can also accumulate to achieve high charge density beams. In this report, we present the design, fabrication, and testing of the 15 MHz ferrite-loaded quarter-wave rf coaxial resonator cavity that will be utilized in the ALPHA storage ring. Topics pertaining to beam lifetime, radiation damping, ferrite-loaded transmission lines, and key cavity parameters will be discussed.
* S.Y. Lee, P.E. Sokol, et al, "The ALPHA Project at IU CEEM," Proceedings of the IPAC2010.
** S.Y. Lee, et al, "A low energy electron storage ring with tunable compaction factor," RSI 78, 2007.

THPPC052

Commissioning and One Year Operation of the 50 kW Solid State Amplifiers of the LNLS Storage Ring RF System

klystron, controls, booster, synchrotron

3404

R.H.A. Farias, J.F.F. Ferrari, C. Pardine, F. Santiago de Oliveira
LNLS, Campinas, Brazil

In December 2010 a pair of high power solid state amplifiers was installed in the RF system of the LNLS electron storage ring. The new amplifiers replaced the UHF klystron system that had been in operation since the machine started operating in 1996. LNLS has been working on solid state amplifiers for more than 10 years since it started a close collaboration with LURE back in 1999 to build an amplifier to drive the booster RF system. From this ongoing collaboration with SOLEIL resulted the design and construction of these two new high power amplifiers, capable of delivering up to 50 kW each at the operating frequency of 476 MHz. Before installation the amplifiers were commissioned in the RF laboratory. We present an overview of the results of those tests as well as a performance evaluation after one year operation of the amplifiers in the storage ring.

THPPD012

Measurement of Injection System of AC Septum Magnets for TPS Storage Ring

septum, injection, shielding, vacuum

3521

F.-Y. Lin, C.-H. Chang, C.-S. Fann, C.-S. Hwang, C.S. Yang
NSRRC, Hsinchu, Taiwan

Taiwan Photon Source (TPS) is a 3 GeV third generation light source and will be operated in top-up injection mode. The leakage field of the septum magnet will dominate the injection performance. The septum magnets, parts of injection system, consist of AC and DC current mode magnets. The AC septum magnet were designed and constructed by NSRRC. In order to verify the magnetic field quality and the leakage field distribution, the search coil probe and the printed circuit technology for long coil probe measurement systems are developed and implemented for magnetic field measurement. This paper will describe the magnetic field measurement system, the magnetic field mapping results and the field shielding performance of AC septum magnet.

THPPD015

Character and Performance of Magnets for the TPS Storage Ring

sextupole, multipole, quadrupole, dipole

3527

J.C. Jan, C.-H. Chang, H.-H. Chen, Y.L. Chu, C.-S. Hwang, C.Y. Kuo, F.-Y. Lin, C.S. Yang, Y.T. Yu
NSRRC, Hsinchu, Taiwan

The Taiwan Photon Source (TPS) is a third-generation light source. The orbit of the electron beam will be controlled with 48 dipoles, 240 quadrupoles, 168 sextupoles and several correctors in the storage ring. The construction of the first magnets for one sector, including prototype magnets, is to be completed during 2011 December. The mechanical dimensions of these magnets have been examined on a precise 3D-coordinate-measuring machine (CMM). The field strength, effective length and multipole errors were inspected with a rotating-coil measurement system (RCS) and a Hall-probe measurement system (HPS). The field center of the quadrupole and sextupole magnets is shimmed with a precise shimming block on the RCS bench. The inaccuracy of the position of the field center will be within 0.01 mm after shimming the feet. This work reports the current status, the construction performance, the mechanical shimming algorithm and the relative construction issue of the high precision magnet.

THPPD037

Design Studies of a Dipole with Elliptical Aperture for the Muon Collider Storage Ring

dipole, collider, quadrupole, electron

3590

M.L. Lopes, V. Kashikhin, J.C. Tompkins, A.V. Zlobin
Fermilab, Batavia, USA
R.B. Palmer
BNL, Upton, Long Island, New York, USA

Funding: Work supported partially by US-MAP and by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy
The requirements and operating conditions for superconducting magnets used in a Muon Collider Storage Ring are challenging. About one third of the beam energy is deposited along the magnets by the decay electrons. As a possible solution an elliptical tungsten absorber could intercept the decay electrons and absorb the heat limiting the heat load on superconducting coils to the acceptable level. In this paper we describe the main design issues of dipoles with an elliptical aperture taking into consideration the field and field quality. The temperature margin and the forces in the coils are presented as well.

THPPD067

Performance of Kicker Pulsers for TPS Project

kicker, injection, power-supply, booster

3665

C.-S. Fann, C.-T. Chen, K.T. Hsu, S.Y. Hsu, J.C. Huang, K.-K. Lin, K.-B. Liu, H.M. Shih, K.L. Tsai
NSRRC, Hsinchu, Taiwan

A set of kicker power suppliers has been designed and fabricated for storage ring beam injection of the Taiwan Photon Source (TPS) project. In order to fulfill the requirements, the performance of the designed units has been bench tested and the results are examined. The matching in four pulsers, the pulse-to-pulse stability and the time jitter are specified according to the beam injection requirements. The engineering evaluation and the measurement results are briefly discussed.

THPPP002

Operation of the HESR Storage Ring of the FAIR Project with Ions and Rare Isotopes

ion, target, electron, antiproton

3722

M. Steck, C. Dimopoulou, A. Dolinskii, T. Katayama, Yu.A. Litvinov, T. Stöhlker
GSI, Darmstadt, Germany
R. Maier, D. Prasuhn, H. Stockhorst
FZJ, Jülich, Germany

The HESR storage ring of the FAIR project is designed for experiments with cooled antiprotons. The HESR receives pre-cooled antiprotons from the Collector Ring CR which is also designed for cooling of rare isotope beams. The magnetic rigidity of 13 Tm is the same for the pre-cooling of antiprotons and rare isotopes in the CR. Therefore the transfer of ions or rare isotopes from the CR to the HESR can be performed under similar condition, except the different polarity of the magnetic components. This is an option for the first stage of the FAIR project when no other storage ring is available for experiments with stored ions. In the HESR the ions can be decelerated or accelerated, like the antiprotons, to energies corresponding to the magnetic rigidity range from 5 to 50 Tm. The planned beam cooling systems of the HESR, stochastic and electron cooling, can be applied to improve the quality of the ion beams in the HESR and support experiments using an internal target or the accumulation of rare isotope beams in the HESR. Scenarios for operating the HESR with ions and rare isotopes as well as achievable performance, beam intensity and quality for internal experiments will be discussed.

THPPR001

Setting Generation for FAIR

controls, synchrotron, proton, optics

3963

D. Ondreka, J. Fitzek, H. Liebermann, R. Müller
GSI, Darmstadt, Germany

The experimental program envisaged for the Facility for Antiproton and Ion Research (FAIR) requires complex operation schemes of its accelerators and beamlines including parallel operation of several experiments. Thus, there is a strong need to develop an appropriate setting generation system, which shall supply consistent settings for all devices across the facility to support the planned parallel operation modes. This system should also provide standard tools for modifying and accessing the settings. These requirements will be met by using LSA, a generic accelerator modeling framework developed at CERN, as basis for the setting generation system. We will report on the status of the setting generation system for FAIR, covering both the implementation of the physics model as well as the extensions to the LSA framework realized within a collaboration with CERN. Results of the first test runs with the existing GSI synchrotron SIS18 will be presented.

THPPR028

Telephone Alarm Broadcasting for TPS RF System

monitoring, SRF, synchrotron, status

4026

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

The Taiwan Photon Source (TPS) consists of three 500-MHz RF systems: two sets RF systems with KEKB-type single-cell SRF modules are used for the 3-GeV storage ring, and one with five-cell Petra cavities at room temperature is used for booster synchrotron. To monitor the status of the RF systems and to broadcast the error/alarm messages to the RF guys, we develop a telephone alarm broadcasting system. This introduces the hardware and software structure of the alarm broadcasting system.

THPPR034

Safety Interlock Implementation of Top-up Operation in the SSRF Control System

controls, injection, booster, linac

4044

L.R. Shen, G.H. Chen, J.F. Chen, W.D. Fang
SINAP, Shanghai, People's Republic of China

The SSRF has performed two years stable operation on decay mode. In order to realize the Top-up operation, the upgrade of control system has been carried out for Top-up trial run. Control system sets up the operation mode control center and accomplishes the upgrading of the MPS system. According to the requirements of the physical design, control system accomplished the design and implementation of the interface for interoperate with PPS system, beam diagnosis system and power supply system and set up the interlocks of the radiation dose, energy, injection efficiency, beam current and beam life in Top-up mode. The kernel of top-up operation safety interlock system is based on hardware interlock system and also provides software interlocking as auxiliary. In the meantime, the reliability of software interlock has been improved.

THPPR057

Feasibility Study Gamma-induced Positron Annihilation Lifetime Spectroscopy in an Electron Storage Ring

laser, positron, electron, target

4103

Y. Taira, H. Toyokawa
AIST, Tsukuba, Ibaraki, Japan
M. Adachi, M. Katoh, S. Tanaka
UVSOR, Okazaki, Japan
N. Yamamoto
Nagoya University, Nagoya, Japan

Funding: This work was supported by Grants-in-Aid for Scientific Research (22360297) and Grant-in-Aid for JSPS Fellows (235193).
Positron annihilation lifetime spectroscopy (PALS) has proved to be very sensitive tool to characterize materials and study defects. However PALS has been restricted to thin samples because of the limited range of positrons in materials. We have developed new techniques for PALS, in which laser Compton scattered (LCS) gamma rays are used to produce positrons inside materials via pair production. Ultra-short gamma ray pulse source* with pulse width of 5 ps (FWHM) generated by 90-degree collision LCS was applied to PALS for the first time. The short pulse width of the gamma-rays that is negligible compared to estimated positron lifetime (100 ps to ns range) is essential to PALS. The experiment was carried out at the UVSOR-II electron storage ring, a 750 MeV synchrotron light source. The positron annihilation lifetime, 199 ± 10 ps, in a bulk sample of lead was successfully measured by using the ultra-short gamma ray pulse.
* Y. Taira, et al., Nucl. Instr. And Meth. A 637 (2011) S116.