IBIC2014 - List of Keywords (timing)

Paper	Title	Other Keywords	Page
MOCZB2	Reference Distribution and Synchronization System for SwissFEL: Concept and First Results	laser, detector, LLRF, controls	29
	S. Hunziker, V.R. Arsov, F. Buechi, M.G. Kaiser, A. Romann, V. Schlott PSI, Villigen PSI, Switzerland P. Orel, S. Zorzut I-Tech, Solkan, Slovenia
	The development of the reference distribution and synchronization system for SwissFEL is driven by ultra-high reference signal stability of SwissFEL LLRF-, beam arrival time monitors (BAM) and laser systems on one hand and cost issues, high reliability/availability and flexibility on the other. Key requirements are down to sub-10fs rms short term as well as sub-10fs peak-peak long term temporal stability for the most critical clients. The system essentially consists of an optical master oscillator with a fiber power amplifier and splitter, from which mutually phase locked optical reference pulses as well as RF reference signals are derived. The former are directly transmitted to the pulsed laser and BAM clients over group delay stabilized fiber-optic links whereas the latter are transmitted via newly developed group delay stabilized radio-over-fiber (RoF) links. Both s- and c-band reference signals use s-band RoF links, whereupon the c-band receiver incorporates an additional ultra-low drift frequency doubler. Furthermore, ultra-low jitter analog laser phase lock loops have been built and digital ones are under development. We will present concepts and first results of sub-10fs rms jitter and 20fs peak-peak long term drift subsystems, as e.g. RoF links, tested in the SwissFEL injector test facility.
	Slides MOCZB2 [2.372 MB]
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MOCZB3	Comparison of Feedback Controller for Link Stabilizing Units of the Laser Based Synchronisation System used at the European XFEL	controls, laser, feedback, electron	34
	M. Heuer, S. Pfeiffer, H. Schlarb DESY, Hamburg, Germany G. Lichtenberg HAW, Hamburg, Germany
	The European X-ray Free Electron Laser will allow scientists to perform experiments with an atomic scale resolution. To perform time resolved experiments at the end of the facility it is essential to provide a highly stable clock signal to all subsystems. The accuracy of this signal is extremely important since it defines limitations of precise measurement devices. A laser based synchronization system is used for the synchronization with an error in sub-femtosecond range. These light pulses are carried by an optical fiber and exposed to external disturbances which changes the optical length of the fiber. For that reason the up to 4 kilometer long fibers are actively stabilized using a controller implemented on the new MicroTCA Platform. Due to the high computation resources of this platform it is possible to attack the time delay of the link system with well known model based feedback control strategies. This contribution shows the design of a model based controller for such a system and compares the control performance of the previously used PID controller with advanced control algorithms at the currently installed laboratory setup.
	Slides MOCZB3 [4.973 MB]
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MOPF08	Beam Profile Measurements in the RHIC Electron Lens using a Pinhole Detector and YAG Screen	electron, controls, software, detector	59
	T.A. Miller, M.R. Costanzo, W. Fischer, B. Frak, D.M. Gassner, X. Gu, A.I. Pikin BNL, Upton, Long Island, New York, USA
	Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy The electron lenses installed in RHIC are equipped with two independent transverse beam profiling systems, namely the Pinhole Detector and YAG screen. A small Faraday cup, with a 0.2mm pinhole mask, intercepts the electron beam while a pre-programmed routine automatically raster scans the beam across the detector face. The collected charge is integrated, digitized and stored in an image type data file that represents the electron beam density. This plungeable detector shares space in the vacuum chamber with a plunging YAG:Ce crystal coated with aluminum. A view port at the downstream extremity of the Collector allows a GigE camera, fitted with a zoom lens, to image the crystal and digitize the profile of a beam pulse. Custom beam profiling software has been written to import both beam image files (pinhole and YAG) and fully characterize the transverse beam profile. The results of these profile measurements are presented here along with a description of the system and operational features. * W. Fischer, et al, "… head-on beam-beam compensation in RHIC", ICFA (BB3013), CERN (2013). **T. Miller, et al, “… eLens pin-hole detector and YAG…“, BIW2012, Newport News, VA, TUPG039
	Poster MOPF08 [6.731 MB]
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MOPF13	Wire Scanner Installation into the MicroTCA Environment for the European XFEL	detector, controls, interface, electronics	73
	T. Lensch, A. Delfs, V. Gharibyan, I. Krouptchenkov, D. Nölle, M. Pelzer, H. Tiessen, M. Werner, K. Wittenburg DESY, Hamburg, Germany
	The European XFEL (E-XFEL) is a 4th generation synchrotron radiation source currently under construction in Hamburg. The 17.5 GeV superconducting accelerator will provide photons simultaneously to several user stations []. For the transverse beam profile measurement in the high energy sections Wire Scanners are used as an essential part of the accelerator diagnostic system, providing the tool to measure small beam size in an almost nondestructive manner. The scanners will be operated in a fast mode, starting from a trigger the wire will be accelerated to 1 m/s and hitting about 100 bunches out of the long bunch train of E-XFEL within a single macropulse. Slow scans with single bunches are also possible. In the first stage 12 stations are planned to be equipped with Wire Scanners where each station consists of two motion units (horizontal and vertical plane). The new concept uses linear servo motors for the motion of the wires and a new mechanical design has been developed at DESY []. This paper describes the electronics developments for the motion part of these Wire Scanners and the integration into the MicroTCA environment. [] "XFEL Technical Design Report", DESY 2006-097, http://xfel.desy.de [**] "OVERVIEW ON E-XFEL STANDARD ELECTRON BEAM DIAGNOSTICS", D.Nölle, BIW 2010, Santa Fe
	Poster MOPF13 [1.760 MB]
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MOPF28	Beam Diagnostics and Timing Monitoring for SuperKEKB Injector Linac	linac, electron, positron, target	110
	F. Miyahara, K. Furukawa, R. Ichimiya, N. Iida, M. Ikeno, H. Kaji, M. Satoh, M. Shoji, T. Suwada, M. Tanaka, Y. Yano KEK, Ibaraki, Japan T. Okazaki EJIT, Hitachi, Ibaraki, Japan
	The SuperKEKB injector linac has multiple operation modes for the electron beam injection into 3 separate rings, SuperKEKB HER, PF (Photon Factory) Ring and PF-AR, and the positron beam injection into the damping ring and the SuperKEKB LER. The operation modes can be switched every 20 milli-second with arbitrary order. The beam parameters such as charge, energy and emittance are different for each of the rings. Moreover, the bunch charge of the electron beam, 5nC, is 5 times higher and the emittance of ~10 mm•mrad is 30 times lower than those of the KEKB injector. Thus, development of BPM readout system with a wide dynamic range and installation of optical fiber detector with a good S/N ratio for the wire scanners and bunch-length monitor have been performed. For stable operation of the linac, many timing signals have to be monitored as well. To that end we have developed 32-bit multi-hit time-to-digital converters (TDCs) with 1-ns resolution. The first beam tests of those systems are reported in this paper.
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MOPD04	Synchronisation of the LHC Betatron Coupling and Phase Advance Measurement System	detector, FPGA, betatron, controls	139
	J. Olexa, M. Gąsior CERN, Geneva, Switzerland
	The new LHC Diode ORbit and OScillation (DOROS) system will provide beam position readings with sub-micrometre resolution and at the same time will be able to perform measurements of local betatron coupling and beam phase advance with micrometre beam excitation. The oscillation sub-system employs gain-controlled RF amplifiers, shared with the orbit system, and followed by dedicated diode detectors to demodulate the beam oscillation signals into the kHz frequency range, subsequently digitized by multi-channel 24-bit ADCs. The digital signals are processed in each front-end with an FPGA and the results of reduced throughput are sent using an Ethernet protocol to a common concentrator, together with the orbit data. The phase advance calculation between multiple Beam Position Monitors (BPMs) requires that all DOROS front-ends have a common phase reference. This paper presents methods used to generate such a reference and to maintain a stable synchronous sampling on all system front-ends. The performance of the DOROS prototype synchronisation is presented based upon laboratory measurements.
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MOPD07	New MTCA.4-based Hardware Developments for the Control of the Optical Synchronization Systems at DESY	laser, controls, detector, LLRF	152
	M. Felber, M.K. Czwalinna, H.T. Duhme, M. Fenner, C. Gerth, M. Heuer, T. Lamb, U. Mavrič, J.M. Mueller, P. Peier, H. Schlarb, S. Schulz, B. Steffen, C. Sydlo, M. Titberidze, T. Walter, R. Wedel, F. Zummack DESY, Hamburg, Germany E. Janas Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland T. Kozak, P. Prędki, K.P. Przygoda TUL-DMCS, Łódź, Poland J. Szewiński NCBJ, Świerk/Otwock, Poland
	Funding: This work has partly been funded by the Helmholtz Validation Fund Project MTCA.4 for Industry (HVF-0016) The optical synchronization group at DESY is operating and continuously enhancing their laser-based synchronization systems for various facilities which need femtosecond-stable timing. These include the free-electron lasers FLASH and the upcoming European XFEL as well as the electron diffraction machine REGAE and the plasma acceleration test facilities. One of the major upgrades under development is the migration of the entire electronic control hardware to the new MTCA.4 platform which was introduced as the new standard for accelerator control in many facilities worldwide. In this paper we present the applied modules and the topology of the new systems. Main advantages are a compact design with higher performance, redundancy, and remote management.
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MOPD12	Novel Femtosecond Level Synchronization of Titanium Sapphire Laser and Relativistic Electron Beams	laser, electron, polarization, plasma	174
	M. Titberidze, F.J. Grüner, A.R. Maier Uni HH, Hamburg, Germany M. Felber, K. Flöttmann, T. Lamb, H. Schlarb, C. Sydlo DESY, Hamburg, Germany F.J. Grüner, A.R. Maier, B. Zeitler CFEL, Hamburg, Germany E. Janas Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
	Laser driven plasma accelerators are offering high gradient (~ 10-100GV/m), high quality (low emittance, short bunch length) electron beams which can be suitable for future compact, bright and tunable light sources. In the framework of the Laboratory for Laser- and beam-driven plasma Acceleration (LAOLA) collaboration at Deutsches Elektronen-Synchrotron (DESY) the external injection experiment for injecting electron bunches from a conventional RF accelerator into the linear plasma wave is in progress. External injection experiments at REGAE (Relativistic Electron gun for Atomic Exploration) require sub-10 fs precision synchronization of laser and electron beams in order to perform a beam scan into the plasma wave by varying the delay between electron beam and laser pulses. In this paper we present a novel optical to microwave synchronization scheme, based on a balanced single output integrated Mach-Zehnder Modulator (MZM). The scheme offers a highly sensitive phase detector between a pulsed 800 nm Ti:Sa laser and a 3GHz microwave reference source. It is virtually independent of input laser power fluctuation and it offers femtosecond long-term precision. Together with the principal of operation of this setup, we will present promising preliminary experimental results of the detector stability.
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MOPD18	ALS Timing System Upgrade	embedded, controls, booster, hardware	187
	J.M. Weber, C.A. Lionberger, W.E. Norum, G.J. Portmann, C. Serrano, E.C. Williams LBNL, Berkeley, California, USA
	The Advanced Light Source (ALS) is in the process of upgrading its timing system as a part of the ALS Instrumentation and Controls Upgrade project. The timing system built upon construction of the machine at the beginning of the 1990s is still in operation today, and a replacement of the machine timing system is under way based on a commercially available solution, benefiting from 20 years of improvements in the fields of digital electronics and optical communications. An overview of the new timing system architecture based on a Micro-Research Finland (MRF) solution is given here.
	Poster MOPD18 [1.235 MB]
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MOPD19	Bunch Arrival Time Monitor for PAL-XFEL	pick-up, LLRF, cavity, electronics	191
	J.H. Hong, J.H. Han, H.-S. Kang, C. Kim, H. Yang PAL, Pohang, Kyungbuk, Republic of Korea
	The X-ray Free Electron Laser project in Pohang Accelerator Laboratory (PAL-XFEL) requires high stability of bunch arrival time, and measurement resolution better than a few femtoseconds. The pickups of the electron Bunch Arrival time Monitor (BAM) for PAL-XFEL have been developed and simulated. The BAM pickups are based on an S-band monopole cavity with two coupling loops. The prototype BAM has been fabricated and installed downstream of the accelerating column at the Injector Test Facility (ITF) for PAL-XFEL. In this paper we will present the recent measurement results on the beam test of the BAM as well as a proposed strategy for developing the BAM for PAL-XFEL.
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MOPD21	Bunch Pattern Measurement via Single Photon Counting at SPEAR3	photon, injection, controls, storage-ring	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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MOPD23	Development Status of SINAP Timing System	FPGA, software, network, PLC	199
	M. Liu, K.C. Chu, C.X. Yin, L.Y. Zhao SINAP, Shanghai, People's Republic of China
	After successful implementation of SINAP timing solution at Pohang Light Source in 2011, we started to upgrade SINAP timing system to version 2. The hardware of SINAP v2 timing system is based on Virtex-6 FPGA chip, and bidirectional event frame transfer is realized in a 2.5Gbps fiber-optic network. In event frame, data transfer functionality substitutes for distributed bus. The structure of timing system is also modified, where a new versatile EVO could be configured as EVG, FANOUT or EVR with optical outputs. Besides standard VME modules, we designed PLC-EVR as well, which is compatible with Yokogawa F3RP61 series. Based on brand new hardware architecture, the jitter performance of SINAP v2 timing system is improved remarkably.
	Poster MOPD23 [4.282 MB]
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TUPF08	Design, Development and Commissioning of a MTCA-Based Button and Strip-Line BPM System for FLASH2	electronics, operation, undulator, electron	320
	B. Lorbeer, N. Baboi, L.P. Petrosyan, F. Schmidt-Föhre DESY, Hamburg, Germany
	The FLASH (Free Electron Laser in Hamburg) facility at DESY (Deutsches Elektronen-Synchrotron) in Germany has been extended by a new undulator line called FLASH2 to provide twice as many experimental stations for users in the future. After the acceleration of the electron bunch train up to 1.2GeV, a part can be kicked into FLASH2, while the other is going to the old undulator line. In order to tune the wavelength of the SASE (Self Amplified Spontaneous Emission), the new line is equipped with variable gap undulators. The commissioning phase of FLASH2 started in early 2014 and is planned to be continued parasitically during user operation in FLASH1. One key point during first beam commissioning is the availability of standard diagnostic devices such as BPM (Beam Position Monitor). In this paper we present the design and first operational experience of a new BPM system for button and strip-line monitors based on MTCA.4. This is referred to as LCBPM (low charge BPM) in contrast to the old systems at FLASH initially designed for bunch charges of 1nC and higher. We summarize the recent analog and digital hardware development progress[,***] and first commissioning experience of this new BPM system at FLASH2 and present a first estimation of its resolution in a large charge range from 1nC down to 100pC and smaller. flash2.desy.de B. Lorbeer et.al.,TUPA19, IBIC2012 * MTCA.4 (Micro Telecommunications Computing Architecture ) for physics **** Frank Schmidt-Foehre et.al.,IPAC2014 Dresden
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TUPD08	YAG:Ce Screen Monitor Using a Gated CCD Camera	emittance, radiation, synchrotron-radiation, collider	426
	T. Naito, T.M. Mitsuhashi KEK, Ibaraki, Japan
	Due to its good spatial resolution, the YAG:Ce screen monitor is often used for small beam profile measurement in the Linac and beam transport line. We constructed a high-resolution YAG:Ce screen monitor at KEK-ATF2 for the observation of small size beams a. We tested two types of screens, one is powder YAG:Ce and the other is single crystal YAG:Ce. Both screens have 50μm thickness. To escape from strong COTR, we applied delayed timing of the gate for the CCD camera. A microscope having a spatial resolution of 6μm was set outside of a vacuum chamber to observe the scintillation light from the YAG:Ce screen. The results of the difference between the two screens, the camera performance with delayed gate, and the optical performance of the microscope will be presented in this session.
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WEIYB1	Direct (Under)Sampling vs Analog Downconversion for BPM Electronics	electronics, pick-up, cavity, detector	486
	M. Wendt CERN, Geneva, Switzerland
	Digital signal processing by means of undersampling the analog signal has become a popular method for acquiring beam position monitor signals. This presentation discusses the technique and its principle limitations, presents today’s technical limits (e.g. in terms of performance of available ADCs), and provides an outlook for the future. It will also try to compare the technique with more tradition analog downmixing and signal processing methods.
	Slides WEIYB1 [3.957 MB]
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WECYB2	NSLS-II RF Beam Position Monitor Comissioning Update	electronics, storage-ring, 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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WEPF02	A Toroid Based Bunch Charge Monitor System with Machine Protection Features for FLASH and XFEL	diagnostics, operation, controls, FPGA	521
	M. Werner, T. Lensch, J. Lund-Nielsen, Re. Neumann, D. Nölle, N. Wentowski DESY, Hamburg, Germany
	For the superconducting linear accelerators FLASH and XFEL, a new toroid based charge measurement system has been designed as a standard diagnostic tool. It is also a sensor for the bunch charge stabilization feedback and for machine protection. The system is based on MTCA.4 technology and will offer a high dynamic range and high sensitivity. The machine protection features will cover recognition of poor transmission between adjacent toroid sensors, bunch pattern consistency checks, and protection of the beam dumps. The concept, an overview of the algorithms, and the implementation will be described. A summary of first operation experience at FLASH will be presented.
	Poster WEPF02 [1.113 MB]
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WEPD08	Beam Jitter Spectra Measurements of the APEX Photoinjector	laser, gun, feedback, electron	652
	H.J. Qian, J.M. Byrd, L.R. Doolittle, Q. Du, D. Filippetto, G. Huang, F. Sannibale, R.P. Wells LBNL, Berkeley, California, USA J. Yang TUB, Beijing, People's Republic of China
	High repetition rate photoinjectors such as the APEX at LBNL are one of the enabling technologies for next generation MHz XFELs. Due to the higher repetition rate, a wider bandwidth is available for feedback systems to achieve ultra-stable beam performance. In a first step to improve APEX beam stability, the noise power spectra of the APEX laser beam and electron beam are characterized in terms of intensity and timing. Possible feedback systems are also discussed.
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WEPD09	Development of a High Speed Beam Position and Phase Monitoring System for the LANSCE Linac	FPGA, EPICS, network, linac	655
	H.A. Watkins, J.D. Gilpatrick, R.C. McCrady LANL, Los Alamos, New Mexico, USA
	Funding: Work supported by the U.S. Department of Energy. The Los Alamos Neutron Science Center (LANSCE) is currently developing beam position and phase measurements (BPPMs) as part of the LANSCE risk mitigation project. BPPM sensors have been installed in the 805-MHz linac and development of the monitoring electronics is near completion. The system utilizes a high speed digitizer coupled with a field programmable gate array (FPGA) mounted in a VPX chassis to measure position, phase and intensity of a variety of beam structures. These systems will be deployed throughout the LANSCE facility. Details of the hardware selection and performance of the system for different timing structures are presented.
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WEPD25	Upgrade Development Progress for the CERN SPS High Bandwidth Transverse Feedback Demonstrator System	kicker, feedback, controls, pick-up	700
	J.E. Dusatko, J.M. Cesaratto, J.D. Fox, C.H. Rivetta SLAC, Menlo Park, California, USA S. De Santis LBNL, Berkeley, California, USA W. Höfle CERN, Geneva, Switzerland
	Funding: Work supported by the U.S. Department of Energy under contract DE-AC02-76SF00515 and the US LHC Accelerator Research Program (LARP) A high bandwidth feedback demonstrator system has been developed for proof of concept transverse intra-bunch closed loop feedback control studies at the CERN SPS. This system contains a beam pickup, analog front end receiver, signal processor, back end driver, power amplifiers and kicker structure. The main signal processing functions are performed digitally, using very fast (4GSa/s) data converters to bring the system signals into and out of the digital domain. The digital signal processing function is flexibly implemented in an FPGA allowing for maximum speed and reconfigurability for testing multiple control algorithms. The signal processor is a modular design consisting of commercial and custom components. This approach allowed for a rapidly-developed prototype to be delivered in a short time with limited resources. Initial beam studies at the SPS using the system prior to the CERN long shutdown one (LS1) have been very encouraging. We are planning several key upgrades to the system, including the signal processor. This paper describes these upgrades and reports on their progress.
	Poster WEPD25 [1.301 MB]
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Paper

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Other Keywords

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MOCZB2

Reference Distribution and Synchronization System for SwissFEL: Concept and First Results

laser, detector, LLRF, controls

29

S. Hunziker, V.R. Arsov, F. Buechi, M.G. Kaiser, A. Romann, V. Schlott
PSI, Villigen PSI, Switzerland
P. Orel, S. Zorzut
I-Tech, Solkan, Slovenia

The development of the reference distribution and synchronization system for SwissFEL is driven by ultra-high reference signal stability of SwissFEL LLRF-, beam arrival time monitors (BAM) and laser systems on one hand and cost issues, high reliability/availability and flexibility on the other. Key requirements are down to sub-10fs rms short term as well as sub-10fs peak-peak long term temporal stability for the most critical clients. The system essentially consists of an optical master oscillator with a fiber power amplifier and splitter, from which mutually phase locked optical reference pulses as well as RF reference signals are derived. The former are directly transmitted to the pulsed laser and BAM clients over group delay stabilized fiber-optic links whereas the latter are transmitted via newly developed group delay stabilized radio-over-fiber (RoF) links. Both s- and c-band reference signals use s-band RoF links, whereupon the c-band receiver incorporates an additional ultra-low drift frequency doubler. Furthermore, ultra-low jitter analog laser phase lock loops have been built and digital ones are under development. We will present concepts and first results of sub-10fs rms jitter and 20fs peak-peak long term drift subsystems, as e.g. RoF links, tested in the SwissFEL injector test facility.

Slides MOCZB2 [2.372 MB]

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MOCZB3

Comparison of Feedback Controller for Link Stabilizing Units of the Laser Based Synchronisation System used at the European XFEL

controls, laser, feedback, electron

34

M. Heuer, S. Pfeiffer, H. Schlarb
DESY, Hamburg, Germany
G. Lichtenberg
HAW, Hamburg, Germany

The European X-ray Free Electron Laser will allow scientists to perform experiments with an atomic scale resolution. To perform time resolved experiments at the end of the facility it is essential to provide a highly stable clock signal to all subsystems. The accuracy of this signal is extremely important since it defines limitations of precise measurement devices. A laser based synchronization system is used for the synchronization with an error in sub-femtosecond range. These light pulses are carried by an optical fiber and exposed to external disturbances which changes the optical length of the fiber. For that reason the up to 4 kilometer long fibers are actively stabilized using a controller implemented on the new MicroTCA Platform. Due to the high computation resources of this platform it is possible to attack the time delay of the link system with well known model based feedback control strategies. This contribution shows the design of a model based controller for such a system and compares the control performance of the previously used PID controller with advanced control algorithms at the currently installed laboratory setup.

Slides MOCZB3 [4.973 MB]

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MOPF08

Beam Profile Measurements in the RHIC Electron Lens using a Pinhole Detector and YAG Screen

electron, controls, software, detector

59

T.A. Miller, M.R. Costanzo, W. Fischer, B. Frak, D.M. Gassner, X. Gu, A.I. Pikin
BNL, Upton, Long Island, New York, USA

Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy
The electron lenses installed in RHIC are equipped with two independent transverse beam profiling systems, namely the Pinhole Detector and YAG screen. A small Faraday cup, with a 0.2mm pinhole mask, intercepts the electron beam while a pre-programmed routine automatically raster scans the beam across the detector face. The collected charge is integrated, digitized and stored in an image type data file that represents the electron beam density. This plungeable detector shares space in the vacuum chamber with a plunging YAG:Ce crystal coated with aluminum. A view port at the downstream extremity of the Collector allows a GigE camera, fitted with a zoom lens, to image the crystal and digitize the profile of a beam pulse. Custom beam profiling software has been written to import both beam image files (pinhole and YAG) and fully characterize the transverse beam profile. The results of these profile measurements are presented here along with a description of the system and operational features.
* W. Fischer, et al, "… head-on beam-beam compensation in RHIC", ICFA (BB3013), CERN (2013).
**T. Miller, et al, “… eLens pin-hole detector and YAG…“, BIW2012, Newport News, VA, TUPG039

Poster MOPF08 [6.731 MB]

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MOPF13

Wire Scanner Installation into the MicroTCA Environment for the European XFEL

detector, controls, interface, electronics

73

T. Lensch, A. Delfs, V. Gharibyan, I. Krouptchenkov, D. Nölle, M. Pelzer, H. Tiessen, M. Werner, K. Wittenburg
DESY, Hamburg, Germany

The European XFEL (E-XFEL) is a 4th generation synchrotron radiation source currently under construction in Hamburg. The 17.5 GeV superconducting accelerator will provide photons simultaneously to several user stations [*]. For the transverse beam profile measurement in the high energy sections Wire Scanners are used as an essential part of the accelerator diagnostic system, providing the tool to measure small beam size in an almost nondestructive manner. The scanners will be operated in a fast mode, starting from a trigger the wire will be accelerated to 1 m/s and hitting about 100 bunches out of the long bunch train of E-XFEL within a single macropulse. Slow scans with single bunches are also possible. In the first stage 12 stations are planned to be equipped with Wire Scanners where each station consists of two motion units (horizontal and vertical plane). The new concept uses linear servo motors for the motion of the wires and a new mechanical design has been developed at DESY [**]. This paper describes the electronics developments for the motion part of these Wire Scanners and the integration into the MicroTCA environment.
[*] "XFEL Technical Design Report", DESY 2006-097, http://xfel.desy.de
[**] "OVERVIEW ON E-XFEL STANDARD ELECTRON BEAM DIAGNOSTICS", D.Nölle, BIW 2010, Santa Fe

Poster MOPF13 [1.760 MB]

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MOPF28

Beam Diagnostics and Timing Monitoring for SuperKEKB Injector Linac

linac, electron, positron, target

110

F. Miyahara, K. Furukawa, R. Ichimiya, N. Iida, M. Ikeno, H. Kaji, M. Satoh, M. Shoji, T. Suwada, M. Tanaka, Y. Yano
KEK, Ibaraki, Japan
T. Okazaki
EJIT, Hitachi, Ibaraki, Japan

The SuperKEKB injector linac has multiple operation modes for the electron beam injection into 3 separate rings, SuperKEKB HER, PF (Photon Factory) Ring and PF-AR, and the positron beam injection into the damping ring and the SuperKEKB LER. The operation modes can be switched every 20 milli-second with arbitrary order. The beam parameters such as charge, energy and emittance are different for each of the rings. Moreover, the bunch charge of the electron beam, 5nC, is 5 times higher and the emittance of ~10 mm•mrad is 30 times lower than those of the KEKB injector. Thus, development of BPM readout system with a wide dynamic range and installation of optical fiber detector with a good S/N ratio for the wire scanners and bunch-length monitor have been performed. For stable operation of the linac, many timing signals have to be monitored as well. To that end we have developed 32-bit multi-hit time-to-digital converters (TDCs) with 1-ns resolution. The first beam tests of those systems are reported in this paper.

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MOPD04

Synchronisation of the LHC Betatron Coupling and Phase Advance Measurement System

detector, FPGA, betatron, controls

139

J. Olexa, M. Gąsior
CERN, Geneva, Switzerland

The new LHC Diode ORbit and OScillation (DOROS) system will provide beam position readings with sub-micrometre resolution and at the same time will be able to perform measurements of local betatron coupling and beam phase advance with micrometre beam excitation. The oscillation sub-system employs gain-controlled RF amplifiers, shared with the orbit system, and followed by dedicated diode detectors to demodulate the beam oscillation signals into the kHz frequency range, subsequently digitized by multi-channel 24-bit ADCs. The digital signals are processed in each front-end with an FPGA and the results of reduced throughput are sent using an Ethernet protocol to a common concentrator, together with the orbit data. The phase advance calculation between multiple Beam Position Monitors (BPMs) requires that all DOROS front-ends have a common phase reference. This paper presents methods used to generate such a reference and to maintain a stable synchronous sampling on all system front-ends. The performance of the DOROS prototype synchronisation is presented based upon laboratory measurements.

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MOPD07

New MTCA.4-based Hardware Developments for the Control of the Optical Synchronization Systems at DESY

laser, controls, detector, LLRF

152

M. Felber, M.K. Czwalinna, H.T. Duhme, M. Fenner, C. Gerth, M. Heuer, T. Lamb, U. Mavrič, J.M. Mueller, P. Peier, H. Schlarb, S. Schulz, B. Steffen, C. Sydlo, M. Titberidze, T. Walter, R. Wedel, F. Zummack
DESY, Hamburg, Germany
E. Janas
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
T. Kozak, P. Prędki, K.P. Przygoda
TUL-DMCS, Łódź, Poland
J. Szewiński
NCBJ, Świerk/Otwock, Poland

Funding: This work has partly been funded by the Helmholtz Validation Fund Project MTCA.4 for Industry (HVF-0016)
The optical synchronization group at DESY is operating and continuously enhancing their laser-based synchronization systems for various facilities which need femtosecond-stable timing. These include the free-electron lasers FLASH and the upcoming European XFEL as well as the electron diffraction machine REGAE and the plasma acceleration test facilities. One of the major upgrades under development is the migration of the entire electronic control hardware to the new MTCA.4 platform which was introduced as the new standard for accelerator control in many facilities worldwide. In this paper we present the applied modules and the topology of the new systems. Main advantages are a compact design with higher performance, redundancy, and remote management.

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MOPD12

Novel Femtosecond Level Synchronization of Titanium Sapphire Laser and Relativistic Electron Beams

laser, electron, polarization, plasma

174

M. Titberidze, F.J. Grüner, A.R. Maier
Uni HH, Hamburg, Germany
M. Felber, K. Flöttmann, T. Lamb, H. Schlarb, C. Sydlo
DESY, Hamburg, Germany
F.J. Grüner, A.R. Maier, B. Zeitler
CFEL, Hamburg, Germany
E. Janas
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland

Laser driven plasma accelerators are offering high gradient (~ 10-100GV/m), high quality (low emittance, short bunch length) electron beams which can be suitable for future compact, bright and tunable light sources. In the framework of the Laboratory for Laser- and beam-driven plasma Acceleration (LAOLA) collaboration at Deutsches Elektronen-Synchrotron (DESY) the external injection experiment for injecting electron bunches from a conventional RF accelerator into the linear plasma wave is in progress. External injection experiments at REGAE (Relativistic Electron gun for Atomic Exploration) require sub-10 fs precision synchronization of laser and electron beams in order to perform a beam scan into the plasma wave by varying the delay between electron beam and laser pulses. In this paper we present a novel optical to microwave synchronization scheme, based on a balanced single output integrated Mach-Zehnder Modulator (MZM). The scheme offers a highly sensitive phase detector between a pulsed 800 nm Ti:Sa laser and a 3GHz microwave reference source. It is virtually independent of input laser power fluctuation and it offers femtosecond long-term precision. Together with the principal of operation of this setup, we will present promising preliminary experimental results of the detector stability.

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MOPD18

ALS Timing System Upgrade

embedded, controls, booster, hardware

187

J.M. Weber, C.A. Lionberger, W.E. Norum, G.J. Portmann, C. Serrano, E.C. Williams
LBNL, Berkeley, California, USA

The Advanced Light Source (ALS) is in the process of upgrading its timing system as a part of the ALS Instrumentation and Controls Upgrade project. The timing system built upon construction of the machine at the beginning of the 1990s is still in operation today, and a replacement of the machine timing system is under way based on a commercially available solution, benefiting from 20 years of improvements in the fields of digital electronics and optical communications. An overview of the new timing system architecture based on a Micro-Research Finland (MRF) solution is given here.

Poster MOPD18 [1.235 MB]

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MOPD19

Bunch Arrival Time Monitor for PAL-XFEL

pick-up, LLRF, cavity, electronics

191

J.H. Hong, J.H. Han, H.-S. Kang, C. Kim, H. Yang
PAL, Pohang, Kyungbuk, Republic of Korea

The X-ray Free Electron Laser project in Pohang Accelerator Laboratory (PAL-XFEL) requires high stability of bunch arrival time, and measurement resolution better than a few femtoseconds. The pickups of the electron Bunch Arrival time Monitor (BAM) for PAL-XFEL have been developed and simulated. The BAM pickups are based on an S-band monopole cavity with two coupling loops. The prototype BAM has been fabricated and installed downstream of the accelerating column at the Injector Test Facility (ITF) for PAL-XFEL. In this paper we will present the recent measurement results on the beam test of the BAM as well as a proposed strategy for developing the BAM for PAL-XFEL.

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MOPD21

Bunch Pattern Measurement via Single Photon Counting at SPEAR3

photon, injection, controls, storage-ring

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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MOPD23

Development Status of SINAP Timing System

FPGA, software, network, PLC

199

M. Liu, K.C. Chu, C.X. Yin, L.Y. Zhao
SINAP, Shanghai, People's Republic of China

After successful implementation of SINAP timing solution at Pohang Light Source in 2011, we started to upgrade SINAP timing system to version 2. The hardware of SINAP v2 timing system is based on Virtex-6 FPGA chip, and bidirectional event frame transfer is realized in a 2.5Gbps fiber-optic network. In event frame, data transfer functionality substitutes for distributed bus. The structure of timing system is also modified, where a new versatile EVO could be configured as EVG, FANOUT or EVR with optical outputs. Besides standard VME modules, we designed PLC-EVR as well, which is compatible with Yokogawa F3RP61 series. Based on brand new hardware architecture, the jitter performance of SINAP v2 timing system is improved remarkably.

Poster MOPD23 [4.282 MB]

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TUPF08

Design, Development and Commissioning of a MTCA-Based Button and Strip-Line BPM System for FLASH2

electronics, operation, undulator, electron

320

B. Lorbeer, N. Baboi, L.P. Petrosyan, F. Schmidt-Föhre
DESY, Hamburg, Germany

The FLASH (Free Electron Laser in Hamburg) facility at DESY (Deutsches Elektronen-Synchrotron) in Germany has been extended by a new undulator line called FLASH2 to provide twice as many experimental stations for users in the future*. After the acceleration of the electron bunch train up to 1.2GeV, a part can be kicked into FLASH2, while the other is going to the old undulator line. In order to tune the wavelength of the SASE (Self Amplified Spontaneous Emission), the new line is equipped with variable gap undulators. The commissioning phase of FLASH2 started in early 2014 and is planned to be continued parasitically during user operation in FLASH1. One key point during first beam commissioning is the availability of standard diagnostic devices such as BPM (Beam Position Monitor). In this paper we present the design and first operational experience of a new BPM system for button and strip-line monitors based on MTCA.4***. This is referred to as LCBPM (low charge BPM) in contrast to the old systems at FLASH initially designed for bunch charges of 1nC and higher. We summarize the recent analog and digital hardware development progress[**,****] and first commissioning experience of this new BPM system at FLASH2 and present a first estimation of its resolution in a large charge range from 1nC down to 100pC and smaller.
* flash2.desy.de
** B. Lorbeer et.al.,TUPA19, IBIC2012
*** MTCA.4 (Micro Telecommunications Computing Architecture ) for physics
**** Frank Schmidt-Foehre et.al.,IPAC2014 Dresden

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TUPD08

YAG:Ce Screen Monitor Using a Gated CCD Camera

emittance, radiation, synchrotron-radiation, collider

426

T. Naito, T.M. Mitsuhashi
KEK, Ibaraki, Japan

Due to its good spatial resolution, the YAG:Ce screen monitor is often used for small beam profile measurement in the Linac and beam transport line. We constructed a high-resolution YAG:Ce screen monitor at KEK-ATF2 for the observation of small size beams a. We tested two types of screens, one is powder YAG:Ce and the other is single crystal YAG:Ce. Both screens have 50μm thickness. To escape from strong COTR, we applied delayed timing of the gate for the CCD camera. A microscope having a spatial resolution of 6μm was set outside of a vacuum chamber to observe the scintillation light from the YAG:Ce screen. The results of the difference between the two screens, the camera performance with delayed gate, and the optical performance of the microscope will be presented in this session.

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WEIYB1

Direct (Under)Sampling vs Analog Downconversion for BPM Electronics

electronics, pick-up, cavity, detector

486

M. Wendt
CERN, Geneva, Switzerland

Digital signal processing by means of undersampling the analog signal has become a popular method for acquiring beam position monitor signals. This presentation discusses the technique and its principle limitations, presents today’s technical limits (e.g. in terms of performance of available ADCs), and provides an outlook for the future. It will also try to compare the technique with more tradition analog downmixing and signal processing methods.

Slides WEIYB1 [3.957 MB]

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WECYB2

NSLS-II RF Beam Position Monitor Comissioning Update

electronics, storage-ring, 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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WEPF02

A Toroid Based Bunch Charge Monitor System with Machine Protection Features for FLASH and XFEL

diagnostics, operation, controls, FPGA

521

M. Werner, T. Lensch, J. Lund-Nielsen, Re. Neumann, D. Nölle, N. Wentowski
DESY, Hamburg, Germany

For the superconducting linear accelerators FLASH and XFEL, a new toroid based charge measurement system has been designed as a standard diagnostic tool. It is also a sensor for the bunch charge stabilization feedback and for machine protection. The system is based on MTCA.4 technology and will offer a high dynamic range and high sensitivity. The machine protection features will cover recognition of poor transmission between adjacent toroid sensors, bunch pattern consistency checks, and protection of the beam dumps. The concept, an overview of the algorithms, and the implementation will be described. A summary of first operation experience at FLASH will be presented.

Poster WEPF02 [1.113 MB]

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WEPD08

Beam Jitter Spectra Measurements of the APEX Photoinjector

laser, gun, feedback, electron

652

H.J. Qian, J.M. Byrd, L.R. Doolittle, Q. Du, D. Filippetto, G. Huang, F. Sannibale, R.P. Wells
LBNL, Berkeley, California, USA
J. Yang
TUB, Beijing, People's Republic of China

High repetition rate photoinjectors such as the APEX at LBNL are one of the enabling technologies for next generation MHz XFELs. Due to the higher repetition rate, a wider bandwidth is available for feedback systems to achieve ultra-stable beam performance. In a first step to improve APEX beam stability, the noise power spectra of the APEX laser beam and electron beam are characterized in terms of intensity and timing. Possible feedback systems are also discussed.

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WEPD09

Development of a High Speed Beam Position and Phase Monitoring System for the LANSCE Linac

FPGA, EPICS, network, linac

655

H.A. Watkins, J.D. Gilpatrick, R.C. McCrady
LANL, Los Alamos, New Mexico, USA

Funding: Work supported by the U.S. Department of Energy.
The Los Alamos Neutron Science Center (LANSCE) is currently developing beam position and phase measurements (BPPMs) as part of the LANSCE risk mitigation project. BPPM sensors have been installed in the 805-MHz linac and development of the monitoring electronics is near completion. The system utilizes a high speed digitizer coupled with a field programmable gate array (FPGA) mounted in a VPX chassis to measure position, phase and intensity of a variety of beam structures. These systems will be deployed throughout the LANSCE facility. Details of the hardware selection and performance of the system for different timing structures are presented.

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WEPD25

Upgrade Development Progress for the CERN SPS High Bandwidth Transverse Feedback Demonstrator System

kicker, feedback, controls, pick-up

700

J.E. Dusatko, J.M. Cesaratto, J.D. Fox, C.H. Rivetta
SLAC, Menlo Park, California, USA
S. De Santis
LBNL, Berkeley, California, USA
W. Höfle
CERN, Geneva, Switzerland

Funding: Work supported by the U.S. Department of Energy under contract DE-AC02-76SF00515 and the US LHC Accelerator Research Program (LARP)
A high bandwidth feedback demonstrator system has been developed for proof of concept transverse intra-bunch closed loop feedback control studies at the CERN SPS. This system contains a beam pickup, analog front end receiver, signal processor, back end driver, power amplifiers and kicker structure. The main signal processing functions are performed digitally, using very fast (4GSa/s) data converters to bring the system signals into and out of the digital domain. The digital signal processing function is flexibly implemented in an FPGA allowing for maximum speed and reconfigurability for testing multiple control algorithms. The signal processor is a modular design consisting of commercial and custom components. This approach allowed for a rapidly-developed prototype to be delivered in a short time with limited resources. Initial beam studies at the SPS using the system prior to the CERN long shutdown one (LS1) have been very encouraging. We are planning several key upgrades to the system, including the signal processor. This paper describes these upgrades and reports on their progress.

Poster WEPD25 [1.301 MB]

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