IBIC2013 - List of Keywords (storage-ring)

Paper	Title	Other Keywords	Page
MOPC09	Development of the Sirius RF BPM Electronics	BPM, controls, pick-up, simulation	63
	D.O. Tavares, R.A. Baron, F.H. Cardoso, S.R. Marques, J.L.B. Neto, L.M. Russo LNLS, Campinas, Brazil A.P. Byszuk, G. Kasprowicz, A.J. Wojenski Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
	A BPM system has been developed for the new low emmitance 3 GeV Brazilian synchrotron light source, Sirius. The Sirius BPM electronics is a modular system based on a PICMG(R) MicroTCA.4 platform using ADC mezzanine cards in ANSI/VITA 57.1 FMC form factor and standalone RF front-end boards. It has been designed under the CERN Open Hardware License (OHL) in a collaboration between Brazilian Synchrotron Light Laboratory (LNLS) and Warsaw University of Technology (WUT). This paper presents: i) overall architecture of the BPM system; ii) performance evaluation of the first prototype of the BPM electronics comprehending beam current, filling pattern and temperature dependencies as well as resolution vs. beam current; and iii) preliminary results with beam at LNLS's UVX storage ring.
	Poster MOPC09 [1.451 MB]

MOPC16	FPGA Based Fast Orbit Feedback Data Acquisition System for Electron and Hadron Storage Rings	feedback, hadron, COSY, BPM	82
	G. Schünemann, P. Hartmann, D. Schirmer, G. Schmidt, P. Towalski, T. Weis DELTA, Dortmund, Germany
	In the course of a BMBF supported development of a fast orbit feedback system for electron and hadron storage rings, in prospect of the upcoming FAIR facility, this paper presents the developed data acquisition system, based on Field Programmable Gateway Array (FPGA) technology, as well as the first results of in-situ measurements. Data was successfully taken at the TU-Dortmunds synchrotron light source DELTA as well as hadron storage rings COSY of the Forschungszentrum Jülich (FZJ) and SIS18 of the GSI Helmholtzzentrum für Schwerionenforschung GmbH (GSI).

MOPC34	Longitudinal Beam Profile Monitor for Investigating the Microbunching Instability at Diamond Light Source	optics, DIAMOND, radiation, longitudinal	143
	W. Shields, R. Bartolini, A.F.D. Morgan, G. Rehm Diamond, Oxfordshire, United Kingdom R. Bartolini, P. Karataev JAI, Oxford, United Kingdom P. Karataev Royal Holloway, University of London, Surrey, United Kingdom
	An investigation into the microbunching instability at Diamond Light Source has recently been conducted. Beyond the instability threshold, the bunch emits bursts of coherent synchrotron radiation with wavelengths comparable to the bunch length or shorter. The operating conditions for producing the instability include both normal optics, and low-alpha optics, where the bunch length can be shortened to a few picoseconds. A Michelson interferometer has been designed and installed utilising a silicon crystal wafer beamsplitter. Large bandwidth, room temperature pyroelectric detectors and low-noise, fast-response Schottky Barrier diode detectors have been employed to generate interferograms. In this paper, we describe the observed spectral content and the resulting calculated bunch length.

MOPC39	Commissioning of a New Streak Camera at TLS for TPS Project	laser, synchrotron, longitudinal, feedback	159
	C.Y. Liao, M.C. Chou, K.T. Hsu, K.H. Hu, C.H. Kuo, C.-C. Kuo, W.K. Lau, C.Y. Wu NSRRC, Hsinchu, Taiwan
	Taiwan Photon Source (TPS) is a 3 GeV synchrotron light source which is being construction at campus of National Synchrotron Radiation Research Center (NSRRC) in Taiwan. A new streak camera equipped with a 125/250 MHz synchroscan unit, a fast/slow single sweep unit, and a dual-time sweep unit is prepared for beam diagnostics, especially for the TPS. An ultra short femtosecond Ti-Sapphire laser was used to evaluate the sub-picosecond temporal resolution of the streak camera and the first beam measurements of the streak camera using synchrotron light from the existing 1.5 GeV Taiwan Light Source (TLS) were performed. The commissioning results are summarized in this report.

TUBL1	NSLS-II BPM and Fast Orbit Feedback System Design and Implementation	BPM, feedback, controls, linac	316
	O. Singh, B. Bacha, A. Blednykh, W.X. Cheng, J.H. De Long, A.J. Della Penna, K. Ha, Y. Hu, B.N. Kosciuk, M.A. Maggipinto, J. Mead, D. Padrazo, I. Pinayev, Y. Tian, K. Vetter, L.-H. Yu BNL, Upton, Long Island, New York, USA
	The National Synchrotron Light Source II is a third generation light source under construction at Brookhaven National Laboratory. The project includes a highly optimized, ultra-low emittance, 3 GeV electron storage ring, linac pre-injector and full energy booster synchrotron. The low emittance requires high performance beam position monitor systems, providing measurement to better than 200 nm resolution; and fast orbit feedback systems, holding orbit to similar level of orbit deviations. The NSLS-II storage ring has 30 cells, each deploying up to 8 RF BPMs and 3 fast weak correctors. Each cell consists of a "cell controller", providing fast orbit feedback system infrastructure. This paper will provide a description of system design and summarize the implementation and status for these systems.
	Slides TUBL1 [5.225 MB]

TUPC07	Design and Impedance Optimization of the SIRIUS BPM Button	BPM, vacuum, impedance, longitudinal	365
	H.O.C. Duarte, S.R. Marques, L. Sanfelici LNLS, Campinas, Brazil
	Design of several BPM Buttons is presented with detail impedance, heat transfer and mechanical analysis. Special attention is given to the application of ceramics as materials with low relative permittivity inside of the BPM Button and to the geometric shape of the BPM Button. The heat dissipation is evaluated based on the loss factor calculated for a 2.65mm bunch length. The narrow-band impedance is discussed and its dependence on applied ceramic materials is compared.
	Poster TUPC07 [1.715 MB]

TUPC18	Development of a Highly Efficient Energy Kicker for Longitudinal Bunch-by-Bunch Feedback	kicker, longitudinal, synchrotron, electron	407
	M. Masaki, T. Fujita, K. Kobayashi, T. Nakamura, H. Ohkuma, M. Oishi, S. Sasaki, M. Shoji JASRI/SPring-8, Hyogo-ken, Japan
	A highly efficient energy kicker has been developed for longitudinal bunch-by-bunch feedback to suppress synchrotron oscillation of a high-current single electron bunch, and to cure possible longitudinal multi-bunch instability if lower beam energy is to be adopted for emittance reduction and electric power saving in a future upgrade plan of SPring-8. Through the performance test using a prototype kicker, a new water-cooled copper kicker was designed and fabricated, and it has been installed in the storage ring. The new kicker consists of three cells with each cavity length of 96 mm, its resonant frequency of 1.65 GHz, which is 3.25 times of RF frequency of the storage ring, and low Q-factor of 4.2. In beam kick test, the synchrotron oscillation amplitude of 0.64 ps was excited by kick voltage with continuous amplitude modulation at synchrotron frequency when the RF input power was 132 W/3cells. The kick voltage evaluated from the experimental result is 920 V/3cells. Shunt impedance of each kicker cell is estimated as 1.1 kΩ. As we intended, the shunt impedance per length is about three times higher than those of widely used waveguide overloaded cavity type kickers.
	Poster TUPC18 [9.117 MB]

TUPC24	The Design Strategy of Orbit Feedback System in the TPS	feedback, BPM, controls, power-supply	423
	C.H. Kuo, J. Chen, Y.-S. Cheng, P.C. Chiu, K.T. Hsu, K.H. Hu, C.Y. Wu NSRRC, Hsinchu, Taiwan
	TPS (Taiwan Photon Source) is a 3 GeV synchrotron light source which is being constructed at NSRRC. The BPM electronic is based on uTCA platform, is used for various request and function reasons. The orbit feedback system design is based on open structure, modularization and highly integration. There are many advantages that orbit feedback system is embedded in the BPM crate with FPGA modules. High throughput backplane, data transfer and processing support rich function for waveform record, diagnostic, beam study and transient analysis. The design and implementation result of the system will be reported in this conference.

TUPC43	Bunch Length Measurement With Streak Camera At SSRF Storage Ring	electron, longitudinal, synchrotron, diagnostics	478
	J. Chen, Z.C. Chen, Y.B. Leng, K.R. Ye, R.X. Yuan SINAP, Shanghai, People's Republic of China
	A streak camera is installed to measure the bunch length of storage ring at SSRF. The principle, structure, configuration and error analysis of the measurement is introduced. Some result of the measurement are analysed to explain the physical meaning of beam status. The system is used in daily operation and machine study at SSRF.

TUPF17	Phase Space Measurement using X-ray Pinhole Camera at SSRF	emittance, photon, quadrupole, radiation	539
	K.R. Ye, J. Chen, Z.C. Chen, G.Q. Huang, Y.B. Leng, L.Y. Yu, W.M. Zhou SINAP, Shanghai, People's Republic of China
	Since 2009 an X-ray pinhole camera that has been used to present the transverse beam size on diagnostic beamline of the storage ring in Shanghai Synchrotron Radiation Facility (SSRF). Transverse beam profiles in the real(x,y) and phase(Y,Y’) spaces are obtained by an X-ray pinhole camera sensitive by moving one pinhole. The large amount of collected data has allowed a detailed reconstruction of the transverse phase space evolution in this paper. An image on a fluorescent screen is observed by a CCD camera，digitized and stored, then the phase space and the real space profiles are reconstructed．A non-linear least square program fits the resultant profiles to a vertical dimensional Gaussian distributions to derive the phase space and emittances for SSRF storage ring．

TUPF20	Low Noise and High Dynamic Range Optical Interferometer Beamsize Measurements	emittance, coupling, synchrotron, background	550
	M.J. Boland SLSA, Clayton, Australia T.M. Mitsuhashi KEK, Ibaraki, Japan K.P. Wootton The University of Melbourne, Melbourne, Australia
	The technique of optical interferometry to measure beam sizes requires a low noise and high dynamic range digitisation system to push the performance to ultra low emittance on storage rings. The next generation of camera sensor Scientific CMOS (sCMOS) promises to provide the technology to improve optical interferometry. A series of measurements was performed on the Australian Synchrotron storage ring using a sCMOS and a intensity imbalance optical interferometer. The coupling in the storage ring was varied from maximum to minimum using the skew quadrupoles and the beam size at the optical diagnostic beamline was varied from over 100 microns to around 1 micron. A comparison is made between interferometer measurements using the sCMOS with and without an intensity imbalance and with previous measurements using a CCD system.

TUPF35	Resonant TE Wave Measurement of Electron Cloud Density Using Phase Detection	resonance, positron, electron, damping	601
	J.P. Sikora Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA S. De Santis LBNL, Berkeley, California, USA
	Funding: This work is supported by the US National Science Foundation PHY-0734867, PHY-1002467, and the US Department of Energy DE-FC02-08ER41538, DE-SC0006505. The resonant TE wave technique can use modulation sidebands for the calculation of electron cloud (EC) density. An alternative is to mix the drive and received signals to form a phase detector. Using this technique, the phase shift across the resonant section of beam-pipe can be observed directly on an oscilloscope. The growth and decay of the EC density has a time constant of roughly 100 ns, while the measured phase shift will include a convolution of the EC density with the impulse response of the resonant beam-pipe - typically about 500 ns. So any estimate of the growth/decay of the cloud requires deconvolution of the measured signal with the response time of the resonance. We have also used this technique to look for evidence of EC density with a lifetime that is long compare to the revolution period of the stored beam. These measurements were made at the Cornell Electron Storage Ring (CESR) which has been reconfigured as a test accelerator (CesrTA) with positron or electron beam energies ranging from 2 GeV to 5 GeV.
	Poster TUPF35 [2.554 MB]

WEPC08	Vibration Measurement and its Effect on Beam Stability at NSLS2	BPM, ground-motion, damping, feedback	674
	W.X. Cheng, A.K. Jain, S. Krinsky, S.K. Sharma, C.J. Spataro BNL, Upton, Long Island, New York, USA
	Vibration measurements have been carried out at NSLS2. The floor has more than 100nm RMS vertical motion during workdays (>1Hz). This motion reduces to 30nm RMS during night and weekends. Traffic on the nearby expressway is considered to be the major source of ground motion. Weather (wind) and utility system induced vibrations are other possible factors on floor motion. Vibrations have been measured at various locations, like the tunnel and experiment floor, HXN long beamline satellite building floor, high stability BPMs, Quadrupole magnets etc. Assume a typical un-correlated motion of Quadrpole magnets of 100nm, beam orbit jitter is around 4-7 microns. Fast orbit feedback will control the orbit stability within 10% of beam size.

WEPC09	Performance of NSLS2 Button BPM	BPM, simulation, booster, vacuum	678
	W.X. Cheng, B. Bacha, B.N. Kosciuk, S. Krinsky, O. Singh BNL, Upton, Long Island, New York, USA
	Several types of button BPMs are used in NSLS2 complex. Coaxial vacuum feedthroughs are used to couple the beam induced signal out. The feedthroughs are designed to match the external transmission line and electronics with characteristic impedance of 50 Ohm. Performances of these BPM feedthroughs are presented in this paper.

WEPC13	Optimisation of the SVD Treatment in the Fast Orbit Correction of the ESRF Storage Ring	BPM, ESRF, feedback, injection	694
	E. Plouviez, F. Epaud, L. Farvacque, J.M. Koch ESRF, Grenoble, France
	The ESRF fast orbit correction system has been in operation since May 2012. The orbit correction scheme relies classically on the calculation of a correction orbit based on the SVD analysis of the response matrix of our 224 BPMs to each of our 96 correctors. The rate of the calculation of the corrections is 10 KHz; we use a PI loop achieving a bandwidth of 150Hz completed with a narrow band pass filter with extra gain at 50Hz. In order to make the best use of the correctors dynamic range and of the resolution of the calculation, it can be useful to limit the bandwidth of loop for the highest order vectors of the SVD, or even to totally remove some of these vectors from the correction down to DC. Removing some of the eigen vectors while avoiding that the loop becomes unstable usually increases a lot the complexity of the matrix calculations: we have developed an algorithm which overcomes this problem; The test of this algorithm is presented. We present also the beneficial effect at high frequency of the limitation of the gain of the correction of the highest SVD eigen vectors on the demand of the peak strength of the correctors and on the resolution of the correction calculation.
	Poster WEPC13 [0.974 MB]

WEPC28	Bunch By Bunch Transverse Beam Position Observation and Analyze During Injection at SSRF	injection, kicker, transverse, betatron	746
	Y.B. Leng, Y.B. Yan, Y. Yang, R.X. Yuan, N. Zhang SSRF, Shanghai, People's Republic of China
	Funding: Work supported by National Science Foundation of China (No. 11075198) Top-up operation has been performed at SSRF since Dec. 2012. Orbit disturbance every 10 minutes decreased the quality of synchrotron radiation. In order to minimize this disturbance the tilts and the timing of injection kickers need to be tuning carefully based on real beam information. A set of button type pick-up and a scope based IOC were employed to capture the transient beam movement with bunch by bunch rate during injection. Several sets of observation and analyze will be discussed in this paper.

WEPC33	Upgrade of Beam Phase Monitors for the ESRF Injector and Storage Ring	booster, injection, BPM, ESRF	757
	K.B. Scheidt, B. Joly ESRF, Grenoble, France
	The measurement of the phase relation between the stored beam in the Storage Ring and the beam circulating in the Booster Synchrotron is now done with high precision and at high speed using a single unit of commercial BPM electronics. The quadrature demodulation, driven by a common PLL, done in these digital electronics on each of its four RF input channels makes the relative measurement of the I/Q components, hence phase relation, easy and strait forward. The RF signals of the relatively low current Booster come from two stripline outputs while that of the Storage Ring from two small BPM buttons. Treating simultaneously four signals, thus with a redundancy of two to measure the phase between two sources, allows to perform intrinsic shot-to-shot cross verifications on resolution and reproducibility. The long-term stability of this device has also been successfully assessed by independent verifications against time and temperature drifts. An identical unit has now been added for phase measurements between the Storage Ring beam and the RF cavity signals. Results with beam and assessment of its scope of performance will be presented on both systems.
	Poster WEPC33 [0.836 MB]

WEPC39	First Tests of the Top-up Gating at Synchrotron SOLEIL	injection, SOLEIL, synchrotron, kicker	775
	J.P. Ricaud, L. Cassinari, P. Dumas, P. Lebasque, A. Nadji SOLEIL, Gif-sur-Yvette, France
	Since 2006, Synchrotron SOLEIL is delivering photons to its beamlines. Until 2012, thanks to the excellent performances of the injection system of the storage ring, the perturbation on the position of the stored beam was small enough to be accepted by the users. For some specific experiments, few beamlines expressed their wish to be able to stop their data acquisition during the injection. To fulfill this need, the diagnostics group of Synchrotron SOLEIL has designed the “TimEX3” board which was integrated into the timing system allowing the gating of the Top-up injection. This design was released as open hardware. Towards this aim, we decided to design it with the open source and free EDA software “KiCad”, and to make it available under the CERN’s Open Hardware Repository.
	Poster WEPC39 [0.521 MB]

WEPF34	Accurate Measurement of Small Electron Beam Currents at the MLS Electron Storage Ring	electron, synchrotron, synchrotron-radiation, radiation	903
	R. Klein, G. Brandt, D. Herzog, R. Thornagel PTB, Berlin, Germany
	The PTB, the German metrology institute, utilizes the electron storage ring MLS in Berlin Adlershof for the realization of the radiometric units in ultraviolet and vacuum ultraviolet spectral range. For this purpose the MLS can be operated as a primary source standard of calculable synchrotron radiation with very flexible parameters, especially in terms of electron beam energy and electron beam current. We report on improvements in the measurement of the electron beam current in the nA and pA range. In this range the electron beam current can be very accurately measured by counting the stored electrons.

Paper

Title

Other Keywords

Page

MOPC09

Development of the Sirius RF BPM Electronics

BPM, controls, pick-up, simulation

63

D.O. Tavares, R.A. Baron, F.H. Cardoso, S.R. Marques, J.L.B. Neto, L.M. Russo
LNLS, Campinas, Brazil
A.P. Byszuk, G. Kasprowicz, A.J. Wojenski
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland

A BPM system has been developed for the new low emmitance 3 GeV Brazilian synchrotron light source, Sirius. The Sirius BPM electronics is a modular system based on a PICMG(R) MicroTCA.4 platform using ADC mezzanine cards in ANSI/VITA 57.1 FMC form factor and standalone RF front-end boards. It has been designed under the CERN Open Hardware License (OHL) in a collaboration between Brazilian Synchrotron Light Laboratory (LNLS) and Warsaw University of Technology (WUT). This paper presents: i) overall architecture of the BPM system; ii) performance evaluation of the first prototype of the BPM electronics comprehending beam current, filling pattern and temperature dependencies as well as resolution vs. beam current; and iii) preliminary results with beam at LNLS's UVX storage ring.

Poster MOPC09 [1.451 MB]

MOPC16

FPGA Based Fast Orbit Feedback Data Acquisition System for Electron and Hadron Storage Rings

feedback, hadron, COSY, BPM

82

G. Schünemann, P. Hartmann, D. Schirmer, G. Schmidt, P. Towalski, T. Weis
DELTA, Dortmund, Germany

In the course of a BMBF supported development of a fast orbit feedback system for electron and hadron storage rings, in prospect of the upcoming FAIR facility, this paper presents the developed data acquisition system, based on Field Programmable Gateway Array (FPGA) technology, as well as the first results of in-situ measurements. Data was successfully taken at the TU-Dortmunds synchrotron light source DELTA as well as hadron storage rings COSY of the Forschungszentrum Jülich (FZJ) and SIS18 of the GSI Helmholtzzentrum für Schwerionenforschung GmbH (GSI).

MOPC34

Longitudinal Beam Profile Monitor for Investigating the Microbunching Instability at Diamond Light Source

optics, DIAMOND, radiation, longitudinal

143

W. Shields, R. Bartolini, A.F.D. Morgan, G. Rehm
Diamond, Oxfordshire, United Kingdom
R. Bartolini, P. Karataev
JAI, Oxford, United Kingdom
P. Karataev
Royal Holloway, University of London, Surrey, United Kingdom

An investigation into the microbunching instability at Diamond Light Source has recently been conducted. Beyond the instability threshold, the bunch emits bursts of coherent synchrotron radiation with wavelengths comparable to the bunch length or shorter. The operating conditions for producing the instability include both normal optics, and low-alpha optics, where the bunch length can be shortened to a few picoseconds. A Michelson interferometer has been designed and installed utilising a silicon crystal wafer beamsplitter. Large bandwidth, room temperature pyroelectric detectors and low-noise, fast-response Schottky Barrier diode detectors have been employed to generate interferograms. In this paper, we describe the observed spectral content and the resulting calculated bunch length.

MOPC39

Commissioning of a New Streak Camera at TLS for TPS Project

laser, synchrotron, longitudinal, feedback

159

C.Y. Liao, M.C. Chou, K.T. Hsu, K.H. Hu, C.H. Kuo, C.-C. Kuo, W.K. Lau, C.Y. Wu
NSRRC, Hsinchu, Taiwan

Taiwan Photon Source (TPS) is a 3 GeV synchrotron light source which is being construction at campus of National Synchrotron Radiation Research Center (NSRRC) in Taiwan. A new streak camera equipped with a 125/250 MHz synchroscan unit, a fast/slow single sweep unit, and a dual-time sweep unit is prepared for beam diagnostics, especially for the TPS. An ultra short femtosecond Ti-Sapphire laser was used to evaluate the sub-picosecond temporal resolution of the streak camera and the first beam measurements of the streak camera using synchrotron light from the existing 1.5 GeV Taiwan Light Source (TLS) were performed. The commissioning results are summarized in this report.

TUBL1

NSLS-II BPM and Fast Orbit Feedback System Design and Implementation

BPM, feedback, controls, linac

316

O. Singh, B. Bacha, A. Blednykh, W.X. Cheng, J.H. De Long, A.J. Della Penna, K. Ha, Y. Hu, B.N. Kosciuk, M.A. Maggipinto, J. Mead, D. Padrazo, I. Pinayev, Y. Tian, K. Vetter, L.-H. Yu
BNL, Upton, Long Island, New York, USA

The National Synchrotron Light Source II is a third generation light source under construction at Brookhaven National Laboratory. The project includes a highly optimized, ultra-low emittance, 3 GeV electron storage ring, linac pre-injector and full energy booster synchrotron. The low emittance requires high performance beam position monitor systems, providing measurement to better than 200 nm resolution; and fast orbit feedback systems, holding orbit to similar level of orbit deviations. The NSLS-II storage ring has 30 cells, each deploying up to 8 RF BPMs and 3 fast weak correctors. Each cell consists of a "cell controller", providing fast orbit feedback system infrastructure. This paper will provide a description of system design and summarize the implementation and status for these systems.

Slides TUBL1 [5.225 MB]

TUPC07

Design and Impedance Optimization of the SIRIUS BPM Button

BPM, vacuum, impedance, longitudinal

365

H.O.C. Duarte, S.R. Marques, L. Sanfelici
LNLS, Campinas, Brazil

Design of several BPM Buttons is presented with detail impedance, heat transfer and mechanical analysis. Special attention is given to the application of ceramics as materials with low relative permittivity inside of the BPM Button and to the geometric shape of the BPM Button. The heat dissipation is evaluated based on the loss factor calculated for a 2.65mm bunch length. The narrow-band impedance is discussed and its dependence on applied ceramic materials is compared.

Poster TUPC07 [1.715 MB]

TUPC18

Development of a Highly Efficient Energy Kicker for Longitudinal Bunch-by-Bunch Feedback

kicker, longitudinal, synchrotron, electron

407

M. Masaki, T. Fujita, K. Kobayashi, T. Nakamura, H. Ohkuma, M. Oishi, S. Sasaki, M. Shoji
JASRI/SPring-8, Hyogo-ken, Japan

A highly efficient energy kicker has been developed for longitudinal bunch-by-bunch feedback to suppress synchrotron oscillation of a high-current single electron bunch, and to cure possible longitudinal multi-bunch instability if lower beam energy is to be adopted for emittance reduction and electric power saving in a future upgrade plan of SPring-8. Through the performance test using a prototype kicker, a new water-cooled copper kicker was designed and fabricated, and it has been installed in the storage ring. The new kicker consists of three cells with each cavity length of 96 mm, its resonant frequency of 1.65 GHz, which is 3.25 times of RF frequency of the storage ring, and low Q-factor of 4.2. In beam kick test, the synchrotron oscillation amplitude of 0.64 ps was excited by kick voltage with continuous amplitude modulation at synchrotron frequency when the RF input power was 132 W/3cells. The kick voltage evaluated from the experimental result is 920 V/3cells. Shunt impedance of each kicker cell is estimated as 1.1 kΩ. As we intended, the shunt impedance per length is about three times higher than those of widely used waveguide overloaded cavity type kickers.

Poster TUPC18 [9.117 MB]

TUPC24

The Design Strategy of Orbit Feedback System in the TPS

feedback, BPM, controls, power-supply

423

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

TPS (Taiwan Photon Source) is a 3 GeV synchrotron light source which is being constructed at NSRRC. The BPM electronic is based on uTCA platform, is used for various request and function reasons. The orbit feedback system design is based on open structure, modularization and highly integration. There are many advantages that orbit feedback system is embedded in the BPM crate with FPGA modules. High throughput backplane, data transfer and processing support rich function for waveform record, diagnostic, beam study and transient analysis. The design and implementation result of the system will be reported in this conference.

TUPC43

Bunch Length Measurement With Streak Camera At SSRF Storage Ring

electron, longitudinal, synchrotron, diagnostics

478

J. Chen, Z.C. Chen, Y.B. Leng, K.R. Ye, R.X. Yuan
SINAP, Shanghai, People's Republic of China

A streak camera is installed to measure the bunch length of storage ring at SSRF. The principle, structure, configuration and error analysis of the measurement is introduced. Some result of the measurement are analysed to explain the physical meaning of beam status. The system is used in daily operation and machine study at SSRF.

TUPF17

Phase Space Measurement using X-ray Pinhole Camera at SSRF

emittance, photon, quadrupole, radiation

539

K.R. Ye, J. Chen, Z.C. Chen, G.Q. Huang, Y.B. Leng, L.Y. Yu, W.M. Zhou
SINAP, Shanghai, People's Republic of China

Since 2009 an X-ray pinhole camera that has been used to present the transverse beam size on diagnostic beamline of the storage ring in Shanghai Synchrotron Radiation Facility (SSRF). Transverse beam profiles in the real(x,y) and phase(Y,Y’) spaces are obtained by an X-ray pinhole camera sensitive by moving one pinhole. The large amount of collected data has allowed a detailed reconstruction of the transverse phase space evolution in this paper. An image on a fluorescent screen is observed by a CCD camera，digitized and stored, then the phase space and the real space profiles are reconstructed．A non-linear least square program fits the resultant profiles to a vertical dimensional Gaussian distributions to derive the phase space and emittances for SSRF storage ring．

TUPF20

Low Noise and High Dynamic Range Optical Interferometer Beamsize Measurements

emittance, coupling, synchrotron, background

550

M.J. Boland
SLSA, Clayton, Australia
T.M. Mitsuhashi
KEK, Ibaraki, Japan
K.P. Wootton
The University of Melbourne, Melbourne, Australia

The technique of optical interferometry to measure beam sizes requires a low noise and high dynamic range digitisation system to push the performance to ultra low emittance on storage rings. The next generation of camera sensor Scientific CMOS (sCMOS) promises to provide the technology to improve optical interferometry. A series of measurements was performed on the Australian Synchrotron storage ring using a sCMOS and a intensity imbalance optical interferometer. The coupling in the storage ring was varied from maximum to minimum using the skew quadrupoles and the beam size at the optical diagnostic beamline was varied from over 100 microns to around 1 micron. A comparison is made between interferometer measurements using the sCMOS with and without an intensity imbalance and with previous measurements using a CCD system.

TUPF35

Resonant TE Wave Measurement of Electron Cloud Density Using Phase Detection

resonance, positron, electron, damping

601

J.P. Sikora
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
S. De Santis
LBNL, Berkeley, California, USA

Funding: This work is supported by the US National Science Foundation PHY-0734867, PHY-1002467, and the US Department of Energy DE-FC02-08ER41538, DE-SC0006505.
The resonant TE wave technique can use modulation sidebands for the calculation of electron cloud (EC) density. An alternative is to mix the drive and received signals to form a phase detector. Using this technique, the phase shift across the resonant section of beam-pipe can be observed directly on an oscilloscope. The growth and decay of the EC density has a time constant of roughly 100 ns, while the measured phase shift will include a convolution of the EC density with the impulse response of the resonant beam-pipe - typically about 500 ns. So any estimate of the growth/decay of the cloud requires deconvolution of the measured signal with the response time of the resonance. We have also used this technique to look for evidence of EC density with a lifetime that is long compare to the revolution period of the stored beam. These measurements were made at the Cornell Electron Storage Ring (CESR) which has been reconfigured as a test accelerator (CesrTA) with positron or electron beam energies ranging from 2 GeV to 5 GeV.

Poster TUPF35 [2.554 MB]

WEPC08

Vibration Measurement and its Effect on Beam Stability at NSLS2

BPM, ground-motion, damping, feedback

674

W.X. Cheng, A.K. Jain, S. Krinsky, S.K. Sharma, C.J. Spataro
BNL, Upton, Long Island, New York, USA

Vibration measurements have been carried out at NSLS2. The floor has more than 100nm RMS vertical motion during workdays (>1Hz). This motion reduces to 30nm RMS during night and weekends. Traffic on the nearby expressway is considered to be the major source of ground motion. Weather (wind) and utility system induced vibrations are other possible factors on floor motion. Vibrations have been measured at various locations, like the tunnel and experiment floor, HXN long beamline satellite building floor, high stability BPMs, Quadrupole magnets etc. Assume a typical un-correlated motion of Quadrpole magnets of 100nm, beam orbit jitter is around 4-7 microns. Fast orbit feedback will control the orbit stability within 10% of beam size.

WEPC09

Performance of NSLS2 Button BPM

BPM, simulation, booster, vacuum

678

W.X. Cheng, B. Bacha, B.N. Kosciuk, S. Krinsky, O. Singh
BNL, Upton, Long Island, New York, USA

Several types of button BPMs are used in NSLS2 complex. Coaxial vacuum feedthroughs are used to couple the beam induced signal out. The feedthroughs are designed to match the external transmission line and electronics with characteristic impedance of 50 Ohm. Performances of these BPM feedthroughs are presented in this paper.

WEPC13

Optimisation of the SVD Treatment in the Fast Orbit Correction of the ESRF Storage Ring

BPM, ESRF, feedback, injection

694

E. Plouviez, F. Epaud, L. Farvacque, J.M. Koch
ESRF, Grenoble, France

The ESRF fast orbit correction system has been in operation since May 2012. The orbit correction scheme relies classically on the calculation of a correction orbit based on the SVD analysis of the response matrix of our 224 BPMs to each of our 96 correctors. The rate of the calculation of the corrections is 10 KHz; we use a PI loop achieving a bandwidth of 150Hz completed with a narrow band pass filter with extra gain at 50Hz. In order to make the best use of the correctors dynamic range and of the resolution of the calculation, it can be useful to limit the bandwidth of loop for the highest order vectors of the SVD, or even to totally remove some of these vectors from the correction down to DC. Removing some of the eigen vectors while avoiding that the loop becomes unstable usually increases a lot the complexity of the matrix calculations: we have developed an algorithm which overcomes this problem; The test of this algorithm is presented. We present also the beneficial effect at high frequency of the limitation of the gain of the correction of the highest SVD eigen vectors on the demand of the peak strength of the correctors and on the resolution of the correction calculation.

Poster WEPC13 [0.974 MB]

WEPC28

Bunch By Bunch Transverse Beam Position Observation and Analyze During Injection at SSRF

injection, kicker, transverse, betatron

746

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

Funding: Work supported by National Science Foundation of China (No. 11075198)
Top-up operation has been performed at SSRF since Dec. 2012. Orbit disturbance every 10 minutes decreased the quality of synchrotron radiation. In order to minimize this disturbance the tilts and the timing of injection kickers need to be tuning carefully based on real beam information. A set of button type pick-up and a scope based IOC were employed to capture the transient beam movement with bunch by bunch rate during injection. Several sets of observation and analyze will be discussed in this paper.

WEPC33

Upgrade of Beam Phase Monitors for the ESRF Injector and Storage Ring

booster, injection, BPM, ESRF

757

K.B. Scheidt, B. Joly
ESRF, Grenoble, France

The measurement of the phase relation between the stored beam in the Storage Ring and the beam circulating in the Booster Synchrotron is now done with high precision and at high speed using a single unit of commercial BPM electronics. The quadrature demodulation, driven by a common PLL, done in these digital electronics on each of its four RF input channels makes the relative measurement of the I/Q components, hence phase relation, easy and strait forward. The RF signals of the relatively low current Booster come from two stripline outputs while that of the Storage Ring from two small BPM buttons. Treating simultaneously four signals, thus with a redundancy of two to measure the phase between two sources, allows to perform intrinsic shot-to-shot cross verifications on resolution and reproducibility. The long-term stability of this device has also been successfully assessed by independent verifications against time and temperature drifts. An identical unit has now been added for phase measurements between the Storage Ring beam and the RF cavity signals. Results with beam and assessment of its scope of performance will be presented on both systems.

Poster WEPC33 [0.836 MB]

WEPC39

First Tests of the Top-up Gating at Synchrotron SOLEIL

injection, SOLEIL, synchrotron, kicker

775

J.P. Ricaud, L. Cassinari, P. Dumas, P. Lebasque, A. Nadji
SOLEIL, Gif-sur-Yvette, France

Since 2006, Synchrotron SOLEIL is delivering photons to its beamlines. Until 2012, thanks to the excellent performances of the injection system of the storage ring, the perturbation on the position of the stored beam was small enough to be accepted by the users. For some specific experiments, few beamlines expressed their wish to be able to stop their data acquisition during the injection. To fulfill this need, the diagnostics group of Synchrotron SOLEIL has designed the “TimEX3” board which was integrated into the timing system allowing the gating of the Top-up injection. This design was released as open hardware. Towards this aim, we decided to design it with the open source and free EDA software “KiCad”, and to make it available under the CERN’s Open Hardware Repository.

Poster WEPC39 [0.521 MB]

WEPF34

Accurate Measurement of Small Electron Beam Currents at the MLS Electron Storage Ring

electron, synchrotron, synchrotron-radiation, radiation

903

R. Klein, G. Brandt, D. Herzog, R. Thornagel
PTB, Berlin, Germany

The PTB, the German metrology institute, utilizes the electron storage ring MLS in Berlin Adlershof for the realization of the radiometric units in ultraviolet and vacuum ultraviolet spectral range. For this purpose the MLS can be operated as a primary source standard of calculable synchrotron radiation with very flexible parameters, especially in terms of electron beam energy and electron beam current. We report on improvements in the measurement of the electron beam current in the nA and pA range. In this range the electron beam current can be very accurately measured by counting the stored electrons.