IBIC2014 - List of Keywords (storage-ring)

Paper	Title	Other Keywords	Page
MOIZB1	NSLS2 Diagnostic Systems Commissioning and Measurements	diagnostics, booster, injection, electronics	16
	W.X. Cheng, B. Bacha, K. Ha, Y. Hu, M.A. Maggipinto, J. Mead, D. Padrazo, O. Singh, H. Xu BNL, Upton, Long Island, New York, USA
	As the newest and most advanced third generation light source, NSLS2 commissioning has started recently. A total of 50mA stored beam was achieved in the storage ring. Most of the diagnostic systems have been commissioned with beams and proved to be critical to the success of machine commissioning. This paper will present beam commissioning results of various diagnostic systems in the NSLS2 injector and storage ring, including profile monitors, current monitors, and position monitors. We will discuss some preliminary machine measurements as well, such as beam current and lifetime, tune, beam stability, filling pattern etc.
	Slides MOIZB1 [6.187 MB]
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MOCZB1	A Picosecond Sampling Electronic “KAPTURE” for Terahertz Synchrotron Radiation	synchrotron-radiation, synchrotron, radiation, detector	24
	C.M. Caselle, M. Brosi, S.A. Chilingaryan, T. Dritschler, N. Hiller, V. Judin, A. Kopmann, A.-S. Müller, L. Petzold, J. Raasch, L. Rota, M. Siegel, N.J. Smale, J.L. Steinmann, M. Vogelgesang, M. Weber, S. Wuensch KIT, Eggenstein-Leopoldshafen, Germany
	For a few years, coherent synchrotron radiation (CSR) generated by short electron bunches has been provided at the ANKA light source. Electron bunches can be filled in up to 184 buckets with a distance between two adjacent bunches of 2 ns corresponding to the RF system frequency of 500 MHz. Arbitrary filling patterns are generated to investigate the interaction of adjacent bunches in CSR. To study the THz emission characteristics over multiple revolutions superconducting YBa2Cu3O7−δ (YBCO) film detectors are used. The intrinsic response time of YBCO thin films is in the order of a few picoseconds only. For fast, continuous sampling of these individual ultra-short terahertz pulses, a novel digitizer system has been developed. The KAPTURE (KArlsruhe Pulse Taking Ultra-fast Readout Electronics) consists of a wideband low-noise amplifier, a picosecond pulse sampling card and a GByte transfer data link back-end readout card. High-end graphic processing units (GPUs) perform real-time data analysis. The KAPTURE system was successfully demonstrated for readout of the intensity fluctuations in the CSR at the ANKA Storage Ring detected in THz range. Four samples are recorded in parallel for each fast pulse with programmable sampling times in the range of 3 to 100 psec. A clean jitter phase locked loop (PLL) provides a clock signal with high temporal accuracy. The back-end card receives the 4 digital samples every 2 ns with 12 bits resolution and transmits the data to the data analysis unit. The readout board is based on programmable logic FPGA and DDR3 memories for on-line data preprocessing and temporary storage. The data is transmitted to the GPU computing node by a fast data transfer links based on a bus master DMA engine connected to PCI express endpoint logic to ensure a continuous high data throughput of up to 4 GByte/s. This heterogeneous real-time system architecture based on FPGA and GPU is used for on-line pulse reconstruction and evaluations and calculates the peak amplitude of each pulse and the time between consecutive bunches with a picosecond time resolution. A Fast Fourier Transform (FFT) is performed on-line for the frequency analysis of the CSR undulations. With the presented acquisition system it was possible to resolve the bursting behavior of single bunches even in a multi-bunch environment to study the bunch-bunch-interactions at ANKA. First results obtained have already been published in the synchrotron machine physic community. The monitoring of bursting for different ANKA parameters using KAPTURE system opens up new analysis and diagnostics possibilities for electron storage rings operating at short bunch lengths.
	Slides MOCZB1 [11.326 MB]
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MOPF07	Construction and Operational Performance of a Horizontally Adjustable Beam Profile Monitor at NSLS-II	injection, septum, controls, vacuum	55
	B.N. Kosciuk, A. Blednykh, S. Seletskiy BNL, Upton, Long Island, New York, USA
	The NSLS-II Synchrotron Light Source is a 3 GeV electron storage ring currently in the early stages of commissioning at Brookhaven National Laboratory. In order to observe the electron beam cross section in the injection region, a specially designed, horizontally adjustable beam profile monitor was installed at the downstream end of the injection septum. It allows the profiles of the injected, bumped and single turn beam to be viewed and measured. In this presentation, we discuss the final design, construction challenges, and operational performance of this novel device.
	Poster MOPF07 [0.953 MB]
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MOPF10	A Compact In-Air X-Ray Detector for Vertical Beam Size Measurement at ALBA	photon, electron, dipole, detector	69
	A.A. Nosych, U. Iriso ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
	An in-air x-ray detector (IXD) was developed for ALBA to study the residual x-rays after traversing the 35mm copper crotch absorbers. The device prototype is placed in-air after such absorber, mounted flush with the vacuum pipe. The remaining x-rays (above 120 keV) generate a visible footprint if they impinge upon a sensitive enough scintillator. We are using a Cerium doped PreLude 420 (LuYSiO:Ce) screen, and the image is observed with a simple optics system mounted on a commercial CCD camera. This measurement allows evaluating the vertical electron beam size with exposure times in the order of seconds. Similar instruments are used at ESRF and ANKA storage rings. This paper presents the results of the first measurements with IXD and describes its potential to be used as a full diagnostics tool for the 3 GeV storage ring of ALBA.
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MOPF20	Diagnosing NSLS-II: A New Advanced Synchrotron Light Source	diagnostics, controls, booster, linac	100
	Y. Hu, L.R. Dalesio, O. Singh, H. Xu BNL, Upton, Long Island, New York, USA
	NSLS-II, the successor to NSLS (National Synchrotron Light Source) at Brookhaven National Lab, is scheduled to be open to users worldwide by 2015 as a world-class advanced synchrotron light source because of its unique features: its half-mile-circumference (792 m) Storage Ring provides the highest beam intensity (500 mA) at medium-energy (3 GeV) with sub-nm-rad horizontal emittance (down to 0.5 nm -rad) and diffraction-limited vertical emittance at a wavelength of 1 Å (<8 pm-rad). As the eyes of NSLS-II accelerators to observe fascinating particle beams, beam diagnostics and controls systems are designed to monitor and diagnose the electron beam quality so that NSLS-II could be tuned up to reach its highest performance. The design and implementation of NSLS-II diagnostics and controls are described. Preliminary commissioning results of NSLS-II accelerators, including Linac, Booster, and Storage Ring, are presented.
	Poster MOPF20 [1.105 MB]
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MOPD17	Single-Shot Electro-Optical Diagnostics at the ANKA Storage Ring	laser, wakefield, electron, operation	182
	N. Hiller, A. Borysenko, E. Hertle, V. Judin, B. Kehrer, A.-S. Müller, M.J. Nasse, M. Schuh, P. Schönfeldt, N.J. Smale, J.L. Steinmann KIT, Karlsruhe, Germany P. Peier, B. Steffen DESY, Hamburg, Germany V. Schlott PSI, Villigen PSI, Switzerland
	Funding: This work is funded by the BMBF contract numbers: 05K10VKC, 05K13VKA. ANKA is the first storage ring in the world with a near-field single-shot electro-optical (EO) bunch profile monitor. The method of electro-optical spectral decoding (EOSD) uses the Pockels effect to modulate the longitudinal electron bunch profile onto a long, chirped laser pulse passing through an EO crystal. The laser pulse is then analyzed with a single-shot spectrometer and from the spectral modulation, the temporal distribution can be extracted. The setup is tuned to a sub-ps resolution (granularity) and can measure down to bunch lengths of 1.5 ps RMS for bunch charges as low as 30 pC. With this setup it is possible to study longitudinal beam dynamics (e. g. microbunching) occurring during ANKA's low-alpha-operation, an operation mode with longitudinally compressed bunches to generate coherent synchrotron radiation in the THz range. In addition to measuring the longitudinal bunch profile, long-ranging wake-fields trailing the electron bunch can also be studied, hinting bunch-bunch interactions.
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MOPD21	Bunch Pattern Measurement via Single Photon Counting at SPEAR3	timing, photon, injection, controls	195
	W.J. Corbett, W.Y. Mok, K. Tian SLAC, Menlo Park, California, USA
	SPEAR3 is a 3GeV storage ring x-ray source that provides up to 500mA circulating beam current in top-up mode. Charge injection occurs on a 5 minute time schedule with the booster synchrotron delivering on-demand single-bunch pulses at 10Hz. In recent years the synchrotron radiation user program has moved in the direction of laser/x-ray pump-probe experiments which utilize a single timing ‘probe’ bunch isolated by 50ns dark space ahead and behind the bunch. In order to quantify bunch purity in adjacent buckets, a time-correlated single-photon counting system has been tested. By monitoring the bunch pattern, is it possible to evaluate when the x-ray probe bunch is sufficiently isolated, and pave the way for shot-by-shot charge injection that maintains all bunches at specified current levels.
	Poster MOPD21 [3.375 MB]
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MOPD24	Diagnostics of and with Laser-Induced Energy Modulation at the DELTA Storage Ring	laser, electron, radiation, undulator	202
	S. Khan, S. Hilbrich, H. Huck, M. Huck, M. Höner, C. Mai, A. Meyer auf der Heide, R. Molo, H. Rast, P. Ungelenk DELTA, Dortmund, Germany
	Funding: This work is supported by the BMBF (05K13PEC) and DFG (INST212/236-1) and by the Land NRW. DELTA is a 1.5-GeV electron storage ring operated by the Center for Synchrotron Radiation at the TU Dortmund University. An interaction between electron bunches and femtosecond laser pulses is routinely used to generate ultrashort pulses of coherent synchrotron radiation at harmonics of the laser wavelength (coherent harmonic generation, CHG) as well as short and coherent pulses in the THz regime. The paper describes diagnostics methods to optimize the laser-electron overlap and to characterize the generated VUV and THz pulses. Furthermore, the laser-electron interaction can be employed as a beam diagnostics tool, e.g. to study the longitudinal steady-state bunch profile as well as dynamic properties during RF-phase modulation, which is applied to improve the beam lifetime.
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TUPF01	NSLS-II RF Beam Position Monitor- System Test and Integration	site, controls, hardware, status	289
	D. Padrazo, A. Caracappa, W.X. Cheng, C. Danneil, A.J. Della Penna, K. Ha, M.A. Maggipinto, J. Mead, O. Singh, K. Vetter BNL, Upton, Long Island, New York, USA
	The NSLS-II Synchrotron Light Source is a 3 GeV electron storage ring currently in the early stages of commissioning at Brookhaven National Laboratory. The RF Beam Position Monitors (RF BPM) are one of the key diagnostics systems required for a successful and efficient commissioning. There are more than 250 RF BPM installed in the injector and the storage ring. Each RF BPM was fully tested, first under laboratory environment and then after installation, utilizing built in pilot tone signal source. These successful tests provided a solid base for the integrity of RF BPM systems, prior to the start of beam commissioning. This paper will describe tests performed and results of system integration.
	Poster TUPF01 [1.068 MB]
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TUPF03	Overview of the Geometrical Non-Linear Effects of Button BPMs and Methodology for Their Efficient Suppression	pick-up, simulation, coupling, vacuum	298
	A.A. Nosych, U. Iriso, A. Olmos ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain M. Wendt CERN, Geneva, Switzerland
	This paper describes an overview of the geometric non-linear effects common to beam position monitors (BPMs) installed in the accelerators and a methodology to correct for these effects. A typical characteristic curve of a pick-up is linear within a limited range from the BPM origin. At larger offsets the non-linearity of the curve is more pronounced and gets worse if the button diameter is small with respect to the beam pipe diameter. The general real-time linearization methods usually utilize linear correction combined with a simplistic polynomial, which may lead to inaccuracies in their limited application. We have developed a more rigorous methodology to suppress the non-linear effects of the BPMs through electromagnetic (EM) simulations and 2D fitting approximations. The focus is mainly on standard button pick-ups for the electron (ALBA) and proton machines (LHC).
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TUPF15	First Results with the Prototypes of New BPM Electronics for the Booster of the ESRF	booster, electronics, injection, Ethernet	351
	K.B. Scheidt ESRF, Grenoble, France
	The 25 year old BPM electronics of the ESRF’s Booster (200 MeV to 6 GeV, 300m, 75 BPM stations) are in process of replacement with new modern acquisition electronics. The design and development of this acquisition system was done in collaboration with the Instrumentation Technologies company and has resulted in a commercial product under the name Libera-Spark. It contains RF filtering & amplification electronics in front of 14 bit & 110 MHz ADCs for 4 channels, followed by a (Xilinx ZYNQ) System_on_Chip for all processing, that also includes the possibility of single bunch filtering directly on the ADC data. It is housed in a compact and robust module that is fully powered over the Ethernet connection and which facilitates its installation close to the BPM stations thereby avoiding long RF cabling. For simplicity and cost economic reasons this Spark is without PLL and adjustable RF attenuators since not needed for Booster BPM applications, but possible in elaborated versions for other applications. Two prototypes were fully tested with beam and results in terms of resolution & stability were assessed since delivery in January.
	Poster TUPF15 [4.855 MB]
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TUPF21	NSLS2 Visible Synchrotron Light Monitor Diagnostic Beamline Commissioning	synchrotron, radiation, dipole, injection	369
	W.X. Cheng, B. Bacha, Y. Hu, O. Singh, H. Xu BNL, Upton, Long Island, New York, USA
	Visible Synchrotron Light Monitor (SLM) beamline has been designed and constructed at NSLS2 storage ring, to characterize the electron beam profile at various machine conditions. Due to carefully alignment, SLM beamline was able to see the first light even before beam circulating the ring. Besides a normal CCD camera to monitor the beam profile, streak camera and gated camera are used to measure the longitudinal and transverse profile to understand the beam dynamics. Measurement results from these cameras will be present in this paper.
	Poster TUPF21 [1.631 MB]
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WECYB2	NSLS-II RF Beam Position Monitor Comissioning Update	timing, electronics, booster, diagnostics	500
	J. Mead, A. Caracappa, W.X. Cheng, C. Danneil, J.H. De Long, A.J. Della Penna, K. Ha, B.N. Kosciuk, M.A. Maggipinto, D. Padrazo, B. Podobedov, O. Singh, Y. Tian, K. Vetter BNL, Upton, Long Island, New York, USA
	The National Synchrotron Light Source II (NSLS-II) is a third generation light source currently in the commissioning stage at Brookhaven National Laboratory. The project includes a highly optimized, ultra-low emittance, 3GeV electron storage ring, linac pre-injector and full energy booster synchrotron. Successful commissioning of the booster began in November 2012, followed by the ongoing commissioning of the NSLS-II 3GeV electron storage ring which began in March 2014. With those particles first injected, came a value realization of the in-house developed RF Beam Position Monitor (RF BPM). This in-house design knowledge proved to be extremely valuable to match BPM configurations and requirements quickly when needed with various injected beam conditions. The RF BPM system was envisioned and undertaken to meet or exceed the demanding applications of a third generation light source. This internal R&D project has since matured to become a fully realized diagnostic system with over 250 modules currently operational. Initial BPM performance and applications will be discussed.
	Slides WECYB2 [3.041 MB]
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WECYB3	Status of the Sirius RF BPM Electronics	electronics, hardware, FPGA, feedback	505
	S.R. Marques, R.A. Baron, G.B.M. Bruno, F.H. Cardoso, L.A. Martins, J.L.B. Neto, L.M. Russo, D.O. Tavares LNLS, Campinas, Brazil
	A modular and open-source RF BPM electronics based on the PICMG(R) MicroTCA.4 and ANSI/VITA 57.1 FMC standards has been developed to be used at Sirius, a 3 GeV low emittance synchrotron light source under construction in Brazil. This paper reports on the latest development advances focusing on bench tests of the second version of the RF front-end and evaluation of the electronics with beam at SPEAR3 (SSRL/SLAC). The interface of the BPM electronics with the orbit feedback system is also discussed.
	Slides WECYB3 [3.265 MB]
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WEPF16	Algorithm to Improve the Beta-Function Measurement and its Evaluation in Storage Rings Lattices	lattice, betatron, optics, collider	574
	A.C. García-Bonilla UNAL, Bogota D.C, Colombia
	In any beam-line, one of the basic measurements during the beam-diagnostics is the measurement of the Beta-Function along the beam-line. This can be achieved in Storage Ring by taking the tune change obtained when varing the intensity of quadrupoles, or by using the matrix response to fit the corresponding parameters, or by shaking the beam to obtain a betatron motion. In accelerators like the LHC, the Beta-Function measurement is done from the Phase Advance Measurement using the Transfer Matrix. In this paper, a study of a new algorithm or numerically approximation for this measurement is presented, as well as the results of the simulations for the LHC and CLIC damping ring. The deduced and implemented algorithm takes into account a fraction of the both transverse planes measurements. A random (uniform) deviation of the MAD-X phase values is studied, by comparison of the proposed algorithm with the traditional one. An improvement close to 30% and 50% on the global error compare to the traditional way to measure the Beta Function is observed; this is for the studied cases using closed-orbits and phase advance values with deviations of 10 or 20 degrees. Postgraduate Student at Universidad Nacional de Colombia
	Poster WEPF16 [0.742 MB]
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WEPF21	Electron Cloud Density Measurements Using Resonant Microwaves at CesrTA	resonance, electron, positron, photon	592
	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. Hardware has recently been installed in the Cornell Electron Storage Ring (CESR) to extend the capability of resonant microwave measurement of electron cloud density. Two new detector locations include aluminum beam-pipe in a dipole magnet and copper beam-pipe in a field free region. Measurements with both positron and electron beams are presented with both beams showing saturation of the electron cloud density in the aluminum chamber. These measurements were made at CESR which has been reconfigured as a test accelerator (CesrTA) with positron or electron beam energies ranging from 2 GeV to 5 GeV.
	Poster WEPF21 [1.988 MB]
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WEPF25	A Fast Quadrupole Magnet for Machine Studies at Diamond	quadrupole, simulation, resonance, photon	605
	A.F.D. Morgan, G. Rehm DLS, Oxfordshire, United Kingdom
	Fast quadrupolar magnets have been demonstrated in various schemes for increasing the coupled bunch instability thresholds, and for measuring the shift of transverse quadrupolar moment oscillation thus probing the transverse quadrupolar impedance. Due to machine upgrades, a ceramic vessel installed in the Diamond storage ring has become temporarily available for use. We decided to take advantage of this situation by designing and installing a simple air core quadrupole magnet which can operate at the fundamental quadrupolar frequencies (~212kHz for the horizontal and ~405kHz for the vertical plane). In the first instance we aim to use it to study the coupled bunch instability thresholds and quadrupolar tune shifts.
	Poster WEPF25 [1.359 MB]
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WEPF31	Sensor Studies for DC Current Transformer Application	ion, synchrotron, instrumentation, feedback	624
	E. Soliman, K. Hofmann TU Darmstadt, Darmstadt, Germany H. Reeg, M. Schwickert GSI, Darmstadt, Germany
	DC Current Transformers (DCCTs) are known since decades as non-intercepting standard tools for online beam current measurement in synchrotrons and storage rings. In general, the measurement principle of commonly used DCCTs is to introduce a modulating AC signal for a pair of ferromagnetic toroid. A passing DC ion beam leads to an asymmetric shift of the hysteresis curves of the toroid pair. However, a drawback for this measurement principle is found at certain revolution frequencies in ring accelerators, when interference caused by the modulating frequency and its harmonics leads to inaccurate readings by the DCCT. Recent developments of magnetic field sensors allow for new approaches towards a DCCT design without using the modulation principle. This paper shows a review of different kinds of usable magnetic sensors, their characteristics and how they could be used in novel DCCT instruments.
	Poster WEPF31 [4.396 MB]
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WEPD03	Conceptual Design of Elliptical Cavity Beam Position Monitors for Heavy Ion Storage Rings	cavity, pick-up, ion, impedance	634
	M.S. Sanjari, X. Chen, P. Hülsmann, Yu.A. Litvinov, F. Nolden, M. Steck, T. Stöhlker GSI, Darmstadt, Germany J. Piotrowski AGH University of Science and Technology, Kraków, Poland
	Funding: M.S.S. acknowledges partial support by the Alliance Program of the Helmholtz Association (HA216/EMMI). X.C. acknowledges funding by the European Commission (PITN-GA-2011-289485). Over 50 years in the history of accelerator physics, RF cavities have been used as beam position and intensity monitors. Their structure has been extensively discussed across numerous papers reporting their successful operation. The application of RF cavities as pick-ups has recently been extended to include radioactive ion beam (RIB) facilities and heavy ion storage rings. These pick-ups allow for very sensitive, accurate, and quick characterisation of ion beams and turn out to be indispensable tools in nuclear as well as atomic physics experiments. A notable example is the resonant pick-up in the ESR at GSI Darmstadt () where single ion detection was achieved for lifetime measurements of radioactive nuclides (). A similar cavity pick-up was installed in CSRe in IMP Lanzhou (*). In this work, we describe a novel conceptual approach that utilizes RF cavities with an elliptical geometry. While requiring a high precision determination of the position and intensity of particle beams, it has to cope with design restriction at heavy-ion storage rings such as large beam pipe apertures. The latter become inevitable at facilities aiming at storing large-emittance beams as, e.g., planned in the future Collector Ring (CR) of the FAIR project at GSI Darmstadt. Simulation results are accompanied by results achieved from bench-top measurements on model cavities. F. Nolden et. al., NIM A, v 659 No 1 pp 69–77 (2011) P. Kienle, F. Bosch et. al., Phys. Lett. B, v 726, 4–5, pp 638–645 (2013) * J. X. Wu et. al., NIM B, v 317, pp 623–628 (2013)
	Poster WEPD03 [1.967 MB]
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WEPD21	BPM Data Correction at SOLEIL	electronics, vacuum, simulation, synchrotron	684
	N. Hubert, B. Béranger, L.S. Nadolski SOLEIL, Gif-sur-Yvette, France
	In a synchrotron light source like SOLEIL, Beam Position Monitors (BPM) are optimized to have the highest sensitivity for an electron beam passing nearby their mechanical center. Nevertheless, this optimization is done to the detriment of the response linearity when the beam is off-centered for dedicated machine physic studies. To correct the geometric non linearity of the BPM, we have applied an algorithm based on a boundary element method. Moreover the BPM electronics is able to provide position data at a turn by turn rate. Unfortunately the filtering process in this electronics mixes the information from one turn to the neighboring turns. An additional demixing algorithm has been set-up to correct this artefact. The paper reports on performances and limitations of those two algorithms that are used at SOLEIL to correct the BPM data.
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WEPD26	Bunch-by-Bunch Feedback Systems at the DELTA Storage Ring used for Beam Diagnostics	feedback, damping, laser, radiation	703
	M. Höner, S. Khan, M. Sommer DELTA, Dortmund, Germany
	Funding: Work supported by the BMBF. At the 1.5-GeV electron storage ring DELTA operated by the TU Dortmund University, a bunch-by-bunch feedback system was installed in 2011. Since then, it is in operation for different beam diagnostic purposes. A fast analysis of bunch-position data allows a real-time multibunch mode analysis during machine operation. In addition, the data analysis can be triggered by external events, e.g. beam losses or the injection process. In this paper, a feedback-based method to measure the damping times of multi-bunch modes is presented. Furthermore, a chromaticity-dependent single-bunch instability is analyzed. Finally, the use of the feedback system in the presence of an RF-phase modulation is presented.
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WEPD27	Commissioning of Bunch-by-Bunch Feedback System for NSLS2 Storage Ring	ion, feedback, kicker, betatron	707
	W.X. Cheng, B. Bacha, Y. Hu, O. Singh, H. Xu BNL, Upton, Long Island, New York, USA D. Teytelman Dimtel, San Jose, USA
	NSLS2 Storage Ring transverse bunch by bunch feedback system has been designed to cure the coupled bunch instabilities, caused by HOM, resistive wall or ions. The system has been constructed, tested and commissioned with beam. Preliminary studies show that the feedback system can suppress single bunch instability. Mode analysis of the unstable coupled bunch motion reveals fast ion instability exist even at relative low current. The bunch by bunch feedback system performance will be presented in this paper.
	Poster WEPD27 [0.623 MB]
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Paper

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Other Keywords

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MOIZB1

NSLS2 Diagnostic Systems Commissioning and Measurements

diagnostics, booster, injection, electronics

16

W.X. Cheng, B. Bacha, K. Ha, Y. Hu, M.A. Maggipinto, J. Mead, D. Padrazo, O. Singh, H. Xu
BNL, Upton, Long Island, New York, USA

As the newest and most advanced third generation light source, NSLS2 commissioning has started recently. A total of 50mA stored beam was achieved in the storage ring. Most of the diagnostic systems have been commissioned with beams and proved to be critical to the success of machine commissioning. This paper will present beam commissioning results of various diagnostic systems in the NSLS2 injector and storage ring, including profile monitors, current monitors, and position monitors. We will discuss some preliminary machine measurements as well, such as beam current and lifetime, tune, beam stability, filling pattern etc.

Slides MOIZB1 [6.187 MB]

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MOCZB1

A Picosecond Sampling Electronic “KAPTURE” for Terahertz Synchrotron Radiation

synchrotron-radiation, synchrotron, radiation, detector

24

C.M. Caselle, M. Brosi, S.A. Chilingaryan, T. Dritschler, N. Hiller, V. Judin, A. Kopmann, A.-S. Müller, L. Petzold, J. Raasch, L. Rota, M. Siegel, N.J. Smale, J.L. Steinmann, M. Vogelgesang, M. Weber, S. Wuensch
KIT, Eggenstein-Leopoldshafen, Germany

For a few years, coherent synchrotron radiation (CSR) generated by short electron bunches has been provided at the ANKA light source. Electron bunches can be filled in up to 184 buckets with a distance between two adjacent bunches of 2 ns corresponding to the RF system frequency of 500 MHz. Arbitrary filling patterns are generated to investigate the interaction of adjacent bunches in CSR. To study the THz emission characteristics over multiple revolutions superconducting YBa2Cu3O7−δ (YBCO) film detectors are used. The intrinsic response time of YBCO thin films is in the order of a few picoseconds only. For fast, continuous sampling of these individual ultra-short terahertz pulses, a novel digitizer system has been developed. The KAPTURE (KArlsruhe Pulse Taking Ultra-fast Readout Electronics) consists of a wideband low-noise amplifier, a picosecond pulse sampling card and a GByte transfer data link back-end readout card. High-end graphic processing units (GPUs) perform real-time data analysis. The KAPTURE system was successfully demonstrated for readout of the intensity fluctuations in the CSR at the ANKA Storage Ring detected in THz range. Four samples are recorded in parallel for each fast pulse with programmable sampling times in the range of 3 to 100 psec. A clean jitter phase locked loop (PLL) provides a clock signal with high temporal accuracy. The back-end card receives the 4 digital samples every 2 ns with 12 bits resolution and transmits the data to the data analysis unit. The readout board is based on programmable logic FPGA and DDR3 memories for on-line data preprocessing and temporary storage. The data is transmitted to the GPU computing node by a fast data transfer links based on a bus master DMA engine connected to PCI express endpoint logic to ensure a continuous high data throughput of up to 4 GByte/s. This heterogeneous real-time system architecture based on FPGA and GPU is used for on-line pulse reconstruction and evaluations and calculates the peak amplitude of each pulse and the time between consecutive bunches with a picosecond time resolution. A Fast Fourier Transform (FFT) is performed on-line for the frequency analysis of the CSR undulations. With the presented acquisition system it was possible to resolve the bursting behavior of single bunches even in a multi-bunch environment to study the bunch-bunch-interactions at ANKA. First results obtained have already been published in the synchrotron machine physic community. The monitoring of bursting for different ANKA parameters using KAPTURE system opens up new analysis and diagnostics possibilities for electron storage rings operating at short bunch lengths.

Slides MOCZB1 [11.326 MB]

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MOPF07

Construction and Operational Performance of a Horizontally Adjustable Beam Profile Monitor at NSLS-II

injection, septum, controls, vacuum

55

B.N. Kosciuk, A. Blednykh, S. Seletskiy
BNL, Upton, Long Island, New York, USA

The NSLS-II Synchrotron Light Source is a 3 GeV electron storage ring currently in the early stages of commissioning at Brookhaven National Laboratory. In order to observe the electron beam cross section in the injection region, a specially designed, horizontally adjustable beam profile monitor was installed at the downstream end of the injection septum. It allows the profiles of the injected, bumped and single turn beam to be viewed and measured. In this presentation, we discuss the final design, construction challenges, and operational performance of this novel device.

Poster MOPF07 [0.953 MB]

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MOPF10

A Compact In-Air X-Ray Detector for Vertical Beam Size Measurement at ALBA

photon, electron, dipole, detector

69

A.A. Nosych, U. Iriso
ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain

An in-air x-ray detector (IXD) was developed for ALBA to study the residual x-rays after traversing the 35mm copper crotch absorbers. The device prototype is placed in-air after such absorber, mounted flush with the vacuum pipe. The remaining x-rays (above 120 keV) generate a visible footprint if they impinge upon a sensitive enough scintillator. We are using a Cerium doped PreLude 420 (LuYSiO:Ce) screen, and the image is observed with a simple optics system mounted on a commercial CCD camera. This measurement allows evaluating the vertical electron beam size with exposure times in the order of seconds. Similar instruments are used at ESRF and ANKA storage rings. This paper presents the results of the first measurements with IXD and describes its potential to be used as a full diagnostics tool for the 3 GeV storage ring of ALBA.

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MOPF20

Diagnosing NSLS-II: A New Advanced Synchrotron Light Source

diagnostics, controls, booster, linac

100

Y. Hu, L.R. Dalesio, O. Singh, H. Xu
BNL, Upton, Long Island, New York, USA

NSLS-II, the successor to NSLS (National Synchrotron Light Source) at Brookhaven National Lab, is scheduled to be open to users worldwide by 2015 as a world-class advanced synchrotron light source because of its unique features: its half-mile-circumference (792 m) Storage Ring provides the highest beam intensity (500 mA) at medium-energy (3 GeV) with sub-nm-rad horizontal emittance (down to 0.5 nm -rad) and diffraction-limited vertical emittance at a wavelength of 1 Å (<8 pm-rad). As the eyes of NSLS-II accelerators to observe fascinating particle beams, beam diagnostics and controls systems are designed to monitor and diagnose the electron beam quality so that NSLS-II could be tuned up to reach its highest performance. The design and implementation of NSLS-II diagnostics and controls are described. Preliminary commissioning results of NSLS-II accelerators, including Linac, Booster, and Storage Ring, are presented.

Poster MOPF20 [1.105 MB]

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MOPD17

Single-Shot Electro-Optical Diagnostics at the ANKA Storage Ring

laser, wakefield, electron, operation

182

N. Hiller, A. Borysenko, E. Hertle, V. Judin, B. Kehrer, A.-S. Müller, M.J. Nasse, M. Schuh, P. Schönfeldt, N.J. Smale, J.L. Steinmann
KIT, Karlsruhe, Germany
P. Peier, B. Steffen
DESY, Hamburg, Germany
V. Schlott
PSI, Villigen PSI, Switzerland

Funding: This work is funded by the BMBF contract numbers: 05K10VKC, 05K13VKA.
ANKA is the first storage ring in the world with a near-field single-shot electro-optical (EO) bunch profile monitor. The method of electro-optical spectral decoding (EOSD) uses the Pockels effect to modulate the longitudinal electron bunch profile onto a long, chirped laser pulse passing through an EO crystal. The laser pulse is then analyzed with a single-shot spectrometer and from the spectral modulation, the temporal distribution can be extracted. The setup is tuned to a sub-ps resolution (granularity) and can measure down to bunch lengths of 1.5 ps RMS for bunch charges as low as 30 pC. With this setup it is possible to study longitudinal beam dynamics (e. g. microbunching) occurring during ANKA's low-alpha-operation, an operation mode with longitudinally compressed bunches to generate coherent synchrotron radiation in the THz range. In addition to measuring the longitudinal bunch profile, long-ranging wake-fields trailing the electron bunch can also be studied, hinting bunch-bunch interactions.

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MOPD21

Bunch Pattern Measurement via Single Photon Counting at SPEAR3

timing, photon, injection, controls

195

W.J. Corbett, W.Y. Mok, K. Tian
SLAC, Menlo Park, California, USA

SPEAR3 is a 3GeV storage ring x-ray source that provides up to 500mA circulating beam current in top-up mode. Charge injection occurs on a 5 minute time schedule with the booster synchrotron delivering on-demand single-bunch pulses at 10Hz. In recent years the synchrotron radiation user program has moved in the direction of laser/x-ray pump-probe experiments which utilize a single timing ‘probe’ bunch isolated by 50ns dark space ahead and behind the bunch. In order to quantify bunch purity in adjacent buckets, a time-correlated single-photon counting system has been tested. By monitoring the bunch pattern, is it possible to evaluate when the x-ray probe bunch is sufficiently isolated, and pave the way for shot-by-shot charge injection that maintains all bunches at specified current levels.

Poster MOPD21 [3.375 MB]

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MOPD24

Diagnostics of and with Laser-Induced Energy Modulation at the DELTA Storage Ring

laser, electron, radiation, undulator

202

S. Khan, S. Hilbrich, H. Huck, M. Huck, M. Höner, C. Mai, A. Meyer auf der Heide, R. Molo, H. Rast, P. Ungelenk
DELTA, Dortmund, Germany

Funding: This work is supported by the BMBF (05K13PEC) and DFG (INST212/236-1) and by the Land NRW.
DELTA is a 1.5-GeV electron storage ring operated by the Center for Synchrotron Radiation at the TU Dortmund University. An interaction between electron bunches and femtosecond laser pulses is routinely used to generate ultrashort pulses of coherent synchrotron radiation at harmonics of the laser wavelength (coherent harmonic generation, CHG) as well as short and coherent pulses in the THz regime. The paper describes diagnostics methods to optimize the laser-electron overlap and to characterize the generated VUV and THz pulses. Furthermore, the laser-electron interaction can be employed as a beam diagnostics tool, e.g. to study the longitudinal steady-state bunch profile as well as dynamic properties during RF-phase modulation, which is applied to improve the beam lifetime.

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TUPF01

NSLS-II RF Beam Position Monitor- System Test and Integration

site, controls, hardware, status

289

D. Padrazo, A. Caracappa, W.X. Cheng, C. Danneil, A.J. Della Penna, K. Ha, M.A. Maggipinto, J. Mead, O. Singh, K. Vetter
BNL, Upton, Long Island, New York, USA

The NSLS-II Synchrotron Light Source is a 3 GeV electron storage ring currently in the early stages of commissioning at Brookhaven National Laboratory. The RF Beam Position Monitors (RF BPM) are one of the key diagnostics systems required for a successful and efficient commissioning. There are more than 250 RF BPM installed in the injector and the storage ring. Each RF BPM was fully tested, first under laboratory environment and then after installation, utilizing built in pilot tone signal source. These successful tests provided a solid base for the integrity of RF BPM systems, prior to the start of beam commissioning. This paper will describe tests performed and results of system integration.

Poster TUPF01 [1.068 MB]

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TUPF03

Overview of the Geometrical Non-Linear Effects of Button BPMs and Methodology for Their Efficient Suppression

pick-up, simulation, coupling, vacuum

298

A.A. Nosych, U. Iriso, A. Olmos
ALBA-CELLS Synchrotron, Cerdanyola del Vallès, Spain
M. Wendt
CERN, Geneva, Switzerland

This paper describes an overview of the geometric non-linear effects common to beam position monitors (BPMs) installed in the accelerators and a methodology to correct for these effects. A typical characteristic curve of a pick-up is linear within a limited range from the BPM origin. At larger offsets the non-linearity of the curve is more pronounced and gets worse if the button diameter is small with respect to the beam pipe diameter. The general real-time linearization methods usually utilize linear correction combined with a simplistic polynomial, which may lead to inaccuracies in their limited application. We have developed a more rigorous methodology to suppress the non-linear effects of the BPMs through electromagnetic (EM) simulations and 2D fitting approximations. The focus is mainly on standard button pick-ups for the electron (ALBA) and proton machines (LHC).

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TUPF15

First Results with the Prototypes of New BPM Electronics for the Booster of the ESRF

booster, electronics, injection, Ethernet

351

K.B. Scheidt
ESRF, Grenoble, France

The 25 year old BPM electronics of the ESRF’s Booster (200 MeV to 6 GeV, 300m, 75 BPM stations) are in process of replacement with new modern acquisition electronics. The design and development of this acquisition system was done in collaboration with the Instrumentation Technologies company and has resulted in a commercial product under the name Libera-Spark. It contains RF filtering & amplification electronics in front of 14 bit & 110 MHz ADCs for 4 channels, followed by a (Xilinx ZYNQ) System_on_Chip for all processing, that also includes the possibility of single bunch filtering directly on the ADC data. It is housed in a compact and robust module that is fully powered over the Ethernet connection and which facilitates its installation close to the BPM stations thereby avoiding long RF cabling. For simplicity and cost economic reasons this Spark is without PLL and adjustable RF attenuators since not needed for Booster BPM applications, but possible in elaborated versions for other applications. Two prototypes were fully tested with beam and results in terms of resolution & stability were assessed since delivery in January.

Poster TUPF15 [4.855 MB]

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TUPF21

NSLS2 Visible Synchrotron Light Monitor Diagnostic Beamline Commissioning

synchrotron, radiation, dipole, injection

369

W.X. Cheng, B. Bacha, Y. Hu, O. Singh, H. Xu
BNL, Upton, Long Island, New York, USA

Visible Synchrotron Light Monitor (SLM) beamline has been designed and constructed at NSLS2 storage ring, to characterize the electron beam profile at various machine conditions. Due to carefully alignment, SLM beamline was able to see the first light even before beam circulating the ring. Besides a normal CCD camera to monitor the beam profile, streak camera and gated camera are used to measure the longitudinal and transverse profile to understand the beam dynamics. Measurement results from these cameras will be present in this paper.

Poster TUPF21 [1.631 MB]

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WECYB2

NSLS-II RF Beam Position Monitor Comissioning Update

timing, electronics, booster, diagnostics

500

J. Mead, A. Caracappa, W.X. Cheng, C. Danneil, J.H. De Long, A.J. Della Penna, K. Ha, B.N. Kosciuk, M.A. Maggipinto, D. Padrazo, B. Podobedov, O. Singh, Y. Tian, K. Vetter
BNL, Upton, Long Island, New York, USA

The National Synchrotron Light Source II (NSLS-II) is a third generation light source currently in the commissioning stage at Brookhaven National Laboratory. The project includes a highly optimized, ultra-low emittance, 3GeV electron storage ring, linac pre-injector and full energy booster synchrotron. Successful commissioning of the booster began in November 2012, followed by the ongoing commissioning of the NSLS-II 3GeV electron storage ring which began in March 2014. With those particles first injected, came a value realization of the in-house developed RF Beam Position Monitor (RF BPM). This in-house design knowledge proved to be extremely valuable to match BPM configurations and requirements quickly when needed with various injected beam conditions. The RF BPM system was envisioned and undertaken to meet or exceed the demanding applications of a third generation light source. This internal R&D project has since matured to become a fully realized diagnostic system with over 250 modules currently operational. Initial BPM performance and applications will be discussed.

Slides WECYB2 [3.041 MB]

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WECYB3

Status of the Sirius RF BPM Electronics

electronics, hardware, FPGA, feedback

505

S.R. Marques, R.A. Baron, G.B.M. Bruno, F.H. Cardoso, L.A. Martins, J.L.B. Neto, L.M. Russo, D.O. Tavares
LNLS, Campinas, Brazil

A modular and open-source RF BPM electronics based on the PICMG(R) MicroTCA.4 and ANSI/VITA 57.1 FMC standards has been developed to be used at Sirius, a 3 GeV low emittance synchrotron light source under construction in Brazil. This paper reports on the latest development advances focusing on bench tests of the second version of the RF front-end and evaluation of the electronics with beam at SPEAR3 (SSRL/SLAC). The interface of the BPM electronics with the orbit feedback system is also discussed.

Slides WECYB3 [3.265 MB]

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WEPF16

Algorithm to Improve the Beta-Function Measurement and its Evaluation in Storage Rings Lattices

lattice, betatron, optics, collider

574

A.C. García-Bonilla
UNAL, Bogota D.C, Colombia

In any beam-line, one of the basic measurements during the beam-diagnostics is the measurement of the Beta-Function along the beam-line. This can be achieved in Storage Ring by taking the tune change obtained when varing the intensity of quadrupoles, or by using the matrix response to fit the corresponding parameters, or by shaking the beam to obtain a betatron motion. In accelerators like the LHC, the Beta-Function measurement is done from the Phase Advance Measurement using the Transfer Matrix. In this paper, a study of a new algorithm or numerically approximation for this measurement is presented, as well as the results of the simulations for the LHC and CLIC damping ring. The deduced and implemented algorithm takes into account a fraction of the both transverse planes measurements. A random (uniform) deviation of the MAD-X phase values is studied, by comparison of the proposed algorithm with the traditional one. An improvement close to 30% and 50% on the global error compare to the traditional way to measure the Beta Function is observed; this is for the studied cases using closed-orbits and phase advance values with deviations of 10 or 20 degrees.
Postgraduate Student at Universidad Nacional de Colombia

Poster WEPF16 [0.742 MB]

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WEPF21

Electron Cloud Density Measurements Using Resonant Microwaves at CesrTA

resonance, electron, positron, photon

592

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.
Hardware has recently been installed in the Cornell Electron Storage Ring (CESR) to extend the capability of resonant microwave measurement of electron cloud density. Two new detector locations include aluminum beam-pipe in a dipole magnet and copper beam-pipe in a field free region. Measurements with both positron and electron beams are presented with both beams showing saturation of the electron cloud density in the aluminum chamber. These measurements were made at CESR which has been reconfigured as a test accelerator (CesrTA) with positron or electron beam energies ranging from 2 GeV to 5 GeV.

Poster WEPF21 [1.988 MB]

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WEPF25

A Fast Quadrupole Magnet for Machine Studies at Diamond

quadrupole, simulation, resonance, photon

605

A.F.D. Morgan, G. Rehm
DLS, Oxfordshire, United Kingdom

Fast quadrupolar magnets have been demonstrated in various schemes for increasing the coupled bunch instability thresholds, and for measuring the shift of transverse quadrupolar moment oscillation thus probing the transverse quadrupolar impedance. Due to machine upgrades, a ceramic vessel installed in the Diamond storage ring has become temporarily available for use. We decided to take advantage of this situation by designing and installing a simple air core quadrupole magnet which can operate at the fundamental quadrupolar frequencies (~212kHz for the horizontal and ~405kHz for the vertical plane). In the first instance we aim to use it to study the coupled bunch instability thresholds and quadrupolar tune shifts.

Poster WEPF25 [1.359 MB]

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WEPF31

Sensor Studies for DC Current Transformer Application

ion, synchrotron, instrumentation, feedback

624

E. Soliman, K. Hofmann
TU Darmstadt, Darmstadt, Germany
H. Reeg, M. Schwickert
GSI, Darmstadt, Germany

DC Current Transformers (DCCTs) are known since decades as non-intercepting standard tools for online beam current measurement in synchrotrons and storage rings. In general, the measurement principle of commonly used DCCTs is to introduce a modulating AC signal for a pair of ferromagnetic toroid. A passing DC ion beam leads to an asymmetric shift of the hysteresis curves of the toroid pair. However, a drawback for this measurement principle is found at certain revolution frequencies in ring accelerators, when interference caused by the modulating frequency and its harmonics leads to inaccurate readings by the DCCT. Recent developments of magnetic field sensors allow for new approaches towards a DCCT design without using the modulation principle. This paper shows a review of different kinds of usable magnetic sensors, their characteristics and how they could be used in novel DCCT instruments.

Poster WEPF31 [4.396 MB]

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WEPD03

Conceptual Design of Elliptical Cavity Beam Position Monitors for Heavy Ion Storage Rings

cavity, pick-up, ion, impedance

634

M.S. Sanjari, X. Chen, P. Hülsmann, Yu.A. Litvinov, F. Nolden, M. Steck, T. Stöhlker
GSI, Darmstadt, Germany
J. Piotrowski
AGH University of Science and Technology, Kraków, Poland

Funding: M.S.S. acknowledges partial support by the Alliance Program of the Helmholtz Association (HA216/EMMI). X.C. acknowledges funding by the European Commission (PITN-GA-2011-289485).
Over 50 years in the history of accelerator physics, RF cavities have been used as beam position and intensity monitors. Their structure has been extensively discussed across numerous papers reporting their successful operation. The application of RF cavities as pick-ups has recently been extended to include radioactive ion beam (RIB) facilities and heavy ion storage rings. These pick-ups allow for very sensitive, accurate, and quick characterisation of ion beams and turn out to be indispensable tools in nuclear as well as atomic physics experiments. A notable example is the resonant pick-up in the ESR at GSI Darmstadt (*) where single ion detection was achieved for lifetime measurements of radioactive nuclides (**). A similar cavity pick-up was installed in CSRe in IMP Lanzhou (***). In this work, we describe a novel conceptual approach that utilizes RF cavities with an elliptical geometry. While requiring a high precision determination of the position and intensity of particle beams, it has to cope with design restriction at heavy-ion storage rings such as large beam pipe apertures. The latter become inevitable at facilities aiming at storing large-emittance beams as, e.g., planned in the future Collector Ring (CR) of the FAIR project at GSI Darmstadt. Simulation results are accompanied by results achieved from bench-top measurements on model cavities.
* F. Nolden et. al., NIM A, v 659 No 1 pp 69–77 (2011)
** P. Kienle, F. Bosch et. al., Phys. Lett. B, v 726, 4–5, pp 638–645 (2013)
*** J. X. Wu et. al., NIM B, v 317, pp 623–628 (2013)

Poster WEPD03 [1.967 MB]

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WEPD21

BPM Data Correction at SOLEIL

electronics, vacuum, simulation, synchrotron

684

N. Hubert, B. Béranger, L.S. Nadolski
SOLEIL, Gif-sur-Yvette, France

In a synchrotron light source like SOLEIL, Beam Position Monitors (BPM) are optimized to have the highest sensitivity for an electron beam passing nearby their mechanical center. Nevertheless, this optimization is done to the detriment of the response linearity when the beam is off-centered for dedicated machine physic studies. To correct the geometric non linearity of the BPM, we have applied an algorithm based on a boundary element method. Moreover the BPM electronics is able to provide position data at a turn by turn rate. Unfortunately the filtering process in this electronics mixes the information from one turn to the neighboring turns. An additional demixing algorithm has been set-up to correct this artefact. The paper reports on performances and limitations of those two algorithms that are used at SOLEIL to correct the BPM data.

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WEPD26

Bunch-by-Bunch Feedback Systems at the DELTA Storage Ring used for Beam Diagnostics

feedback, damping, laser, radiation

703

M. Höner, S. Khan, M. Sommer
DELTA, Dortmund, Germany

Funding: Work supported by the BMBF.
At the 1.5-GeV electron storage ring DELTA operated by the TU Dortmund University, a bunch-by-bunch feedback system was installed in 2011. Since then, it is in operation for different beam diagnostic purposes. A fast analysis of bunch-position data allows a real-time multibunch mode analysis during machine operation. In addition, the data analysis can be triggered by external events, e.g. beam losses or the injection process. In this paper, a feedback-based method to measure the damping times of multi-bunch modes is presented. Furthermore, a chromaticity-dependent single-bunch instability is analyzed. Finally, the use of the feedback system in the presence of an RF-phase modulation is presented.

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WEPD27

Commissioning of Bunch-by-Bunch Feedback System for NSLS2 Storage Ring

ion, feedback, kicker, betatron

707

W.X. Cheng, B. Bacha, Y. Hu, O. Singh, H. Xu
BNL, Upton, Long Island, New York, USA
D. Teytelman
Dimtel, San Jose, USA

NSLS2 Storage Ring transverse bunch by bunch feedback system has been designed to cure the coupled bunch instabilities, caused by HOM, resistive wall or ions. The system has been constructed, tested and commissioned with beam. Preliminary studies show that the feedback system can suppress single bunch instability. Mode analysis of the unstable coupled bunch motion reveals fast ion instability exist even at relative low current. The bunch by bunch feedback system performance will be presented in this paper.

Poster WEPD27 [0.623 MB]

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