Keyword: controls
Paper Title Other Keywords Page
MOBL04 LHC Online Chromaticity Measurement - Experience After One Year of Operation injection, operation, feedback, hardware 20
  • K. Fuchsberger, G.H. Hemelsoet
    CERN, Geneva, Switzerland
  Hardware and infrastructural requirements to measure chromaticity in the LHC were available since the beginning. However, the calculation of the chromaticity was mostly made offline. This gap was closed in 2015 by the development of a dedicated application for the LHC control room, which takes the measured data and produces estimates for the chromaticity values immediately online and allows to correct chroma and tune accordingly. This tool proved to be essential during commissioning as well as during every injection-phase of the LHC. It became particularly important during the intensity ramp-up with 25ns where good control of the chromaticity became crucial at injection. This paper describes the concepts and algorithms behind this tool, the experience gained as well as further plans for improvements.  
slides icon Slides MOBL04 [7.414 MB]  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOBL04  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
MOPG06 First Beam Tests of the APS MBA Upgrade Orbit Feedback Controller feedback, hardware, power-supply, storage-ring 39
  • N. Sereno, N.D. Arnold, A.R. Brill, H. Bui, J. Carwardine, G. Decker, B. Deriy, L. Emery, R.I. Farnsworth, T. Fors, R.T. Keane, F. Lenkszus, R.M. Lill, D.R. Paskvan, A.F. Pietryla, H. Shang, S.E. Shoaf, S. Veseli, J. Wang, S. Xu, B.X. Yang
    ANL, Argonne, Illinois, USA
  Funding: Work supported by the U.S. Department of Energy, Office of Science, under Contract No. DE-AC02-06CH11357
The new orbit feedback system required for the APS multi-bend acromat (MBA) ring must meet challenging beam stability requirements. The AC stability requirement is to correct rms beam motion to 10 \% the rms beam size at the insertion device source points from 0.01 to 1000 Hz. The vertical plane represents the biggest challenge for AC stability which is required to be 400 nm rms for a 4 micron vertical beam size. In addition long term drift over a period of 7 days is required to be 1 micron or less at insertion device BPMs and 2 microns for arc bpms. We present test results of the MBA prototype orbit feedback controller (FBC) in the APS storage ring. In this test, four insertion device BPMs were configured to send data to the FBC for processing into four fast corrector setpoints. The configuration of four bpms and four fast correctors creates a 4-bump and the configuration of fast correctors is similar to what will be implemented in the MBA ring. We report on performance benefits of increasing the sampling rate by a factor of 15 to 22.6 kHz over the existing APS orbit feedback system, limitations due to existing storage ring hardware and MBA orbit feedback design.
poster icon Poster MOPG06 [6.490 MB]  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG06  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
MOPG09 The Orbit Correction Scheme of the New EBS of the ESRF feedback, electronics, storage-ring, sextupole 51
  • E. Plouviez, F. Uberto
    ESRF, Grenoble, France
  The ESRF storage ring is going to be upgraded into an Extremely Bright Source(EBS). The orbit correction system of the EBS ring will require 320 BPMs and 288 correctors instead of 224 BPMs and 96 correctors for the present ring. On the new ring, we are planning to reuse 192 Libera Brilliance electronics and 96 fast correctors power supplies and the 8 FPGA controllers of the present system and to add 128 new BPMs electronics and 196 new correctors power supplies. These new BPM electronics and power supplies will not have the fast 10 KHz data broadcast capability of the components of the present system. So we plan to implement an hybrid slow/ fast correction scheme on the SR of the EBS in order to reuse the present fast orbit correction system on a reduced set of the BPMs and correctors and combine this fast orbit correction with an orbit correction performed at a slower rate using the full set of BPMs and correctors. We have made simulations to predict the efficiency of this scheme for the EBS and tested on the present ring a similar orbit correction scheme using only 160 BPMs and 64 correctors for the fast corrections . We present the results of our simulations and experiments.  
poster icon Poster MOPG09 [4.054 MB]  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG09  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
MOPG15 BPM Electronics for the ELBE Linear Accelerator - a Comparison electronics, embedded, pick-up, instrumentation 75
  • U. Lehnert, A. Büchner, B. Lange, R. Schurig, R. Steinbrück
    HZDR, Dresden, Germany
  The ELBE linear accelerator supports a great variety of possible beam options ranging from single bunches to 1.6 mA CW beams at 13 MHz bunch repetition rate. Accordingly high are the dynamic range requirements for the BPM system. Recently, we are testing the Libera Spark EL electronics to supplement our home-built BPM electronics for low repetition rate operation. Here, we discuss the advantages and disadvantages of the two completely different detection schemes. For integration of the Libera Spark EL into our accelerator control system we are implementing an OPC-UA server embedded into the device. The server is based on the free Open62541 protocol stack which is available as open source under the LGPL.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG15  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
MOPG17 Performance Test of the Next Generation X-Ray Beam Position Monitor System for the APS Upgrade undulator, photon, operation, storage-ring 78
  • B.X. Yang, Y. Jaski, S.H. Lee, F. Lenkszus, M. Ramanathan, N. Sereno, F. Westferro
    ANL, Argonne, Illinois, USA
  Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
The Advanced Photon Source is developing its next major upgrade (APS-U) based on the multi-bend achromat lattice. Improved beam stability is critical for this upgrade and will require keeping short-time beam angle change below 0.25 μrad and long-term angle drift below 0.5 micro-radian. A reliable white x-ray beam diagnostic system in the front end is a key part of the planned beam stabilization system for the APS-U. This system includes an x-ray beam position monitor (XBPM) based on x-ray fluorescence (XRF) from two specially designed GlidCop A-15 absorbers, a second XBPM using XRF photons from the Exit Mask, and two white beam intensity monitors using XRF from the photon shutter and Compton-scattered photons from the front end beryllium window. We present orbit stability data for the first XBPM used in the feedback control during user operations, as well as test data from the second XBPM and the intensity monitors. The data demonstrated that the XBPM system meets the APS-U beam stability requirements.
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG17  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
MOPG20 Optimized Beam Loss Monitor System for the ESRF detector, injection, electron, vacuum 86
  • K.B. Scheidt, F. Ewald
    ESRF, Grenoble, France
  • P. Leban
    I-Tech, Solkan, Slovenia
  Monitoring of the 6 GeV electron losses around the ESRF storage ring is presently done by a hybrid system consisting of ionization chambers and scintillators. It allows a rough localization of the losses, but has numerous limitations : size, weight, time-resolution, sensitivity, versatility, and costs. A new system was developed consisting of a detector head (BLD) and the electronics for signal acquisition and control (BLM). The BLD is compact, based on a scintillator coupled to a small photo-multiplier module. The BLM controls 4 independent BLDs and acquires data with sampling rates up to 125 MHz. Measurements performed on different configurations of BLD prototypes have lead to an optimized design that allows, together with the flexible signal processing performed in the BLM, to cover a wide range of applications: measurement of fast and strong losses during injection is just as well possible as detection of very small variations of weak losses during the slow current decay. This paper describes the BLD/BLM design, its functionality and performance characteristics, and shows results from prototypes installed in the injection zone and in close vicinity to in-vacuum undulators.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG20  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
MOPG25 Industrialisation of Cavity BPMs cavity, electronics, FPGA, simulation 98
  • E. Yamakawa, S.T. Boogert, A. Lyapin
    JAI, Egham, Surrey, United Kingdom
  • S. Syme
    FMB Oxford, Oxford, United Kingdom
  The industrialisation project of a cavity beam position monitor (CBPM) has been commissioned aiming at providing reliable and economical CBPM systems for future Free Electron Lasers (FEL) and similar linac-based facilities. The first prototype of a CBPM system was built at Versatile Electron Linear Accelerator (VELA) in Daresbury Laboratory. We report on the measurement results from the first prototype of our system at VELA and current developments of CBPMs, down-converter electronics and DAQ system.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG25  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
MOPG48 Optimized Cryogenic Current Comparator for CERN's Low-Energy Antiproton Facilities antiproton, cryogenics, injection, flattop 161
  • M.F. Fernandes, D. Alves, T. Koettig, A. Lees, E. Oponowicz, J. Tan
    CERN, Geneva, Switzerland
  • M.F. Fernandes, C.P. Welsch
    The University of Liverpool, Liverpool, United Kingdom
  • R. Geithner, R. Neubert, T. Stöhlker
    HIJ, Jena, Germany
  • R. Geithner, R. Neubert, T. Stöhlker
    IOQ, Jena, Germany
  • M. Schwickert
    GSI, Darmstadt, Germany
  • C.P. Welsch
    Cockcroft Institute, Warrington, Cheshire, United Kingdom
  Funding: This project has received funding from the European Unions Seventh Framework Programme for research, technological development and demonstration under grant agreement number 289485.
Non-perturbative measurement of low-intensity charged particle beams is particularly challenging for beam diagnostics due to the low amplitude of the induced electromagnetic fields. In the low-energy Antiproton Decelerator (AD) and the future Extra Low ENergy Antiproton (ELENA) rings at CERN, an absolute measurement of the beam intensity is essential to monitor operational efficiency and provide important calibration data for all AD experiments. Cryogenic Current Comparators (CCC) based on Superconducting QUantum Interference Device (SQUID) have in the past been used for the measurement of beams in the nA range, showing a very good current resolution. However these were unable to provide a measurement of short bunched beams, due to the slew-rate limitation of SQUID devices and their strong susceptibility to external perturbations. Here, we present the measurements and results obtained during 2016 with a CCC system developed for the Antiproton Decelerator, which has been optimized to overcome these earlier limitations in terms of current resolution, system stability, the ability to cope with short bunched beams, and immunity to mechanical vibrations.
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG48  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
MOPG70 Transverse Beam Profiling and Vertical Emittance Control with a Double-Slit Stellar Interferometer electron, coupling, optics, radiation 236
  • W.J. Corbett, X. Huang, J. Wu
    SLAC, Menlo Park, California, USA
  • C.L. Li, W.J. Zhang
    East China University of Science and Technology, Shanghai, People's Republic of China
  • T.M. Mitsuhashi
    KEK, Ibaraki, Japan
  • Y.H. Xu
    DongHua University, Songjiang, People's Republic of China
  • W.J. Zhang
    University of Saskatchewan, Saskatoon, Canada
  Double-slit interferometers are useful tools to measure the transverse the cross-section of relativistic charged particle beams emitting incoherent synchrotron radiation. By rotating the double-slit about the beam propagation axis, the transverse beam profile can be reconstructed including beam tilt at the source. The interferometer can also be used as a sensitive monitor for vertical emittance control. In this paper we outline a simple derivation of the Van Cittert-Zernike theorem, present results for a rotating double-slit measurement and demonstrate application of the interferometer to vertical emittance control using the Robust Conjugate Direction Search (RCDS) optimization algorithm.  
poster icon Poster MOPG70 [1.362 MB]  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG70  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
MOPG77 Design and Application of the Wire Scanner for CADS Proton Beams emittance, proton, rfq, instrumentation 265
  • L. Yu, J.S. Cao, H. Geng, C. Meng, Y.F. Sui
    IHEP, Beijing, People's Republic of China
  CADS Injector-I accelerator is a 10-mA 10-MeV CW proton linac, which uses a 3.2-MeV normal conducting 4-Vane RFQ and superconducting single-spoke cavities for accelerating. Eight wire scanners are designed and used to measure the beam profile of CADS Injector-I. In this paper principal of operation, instrumentation and programming of these wire scanners are discussed. Some results of beam profile and emittance measurement with these wire scanners are also presented.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG77  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
MOPG78 Scintillation and OTR Screen Characterization with a 440 GeV/c Proton Beam in Air at the CERN HiRadMat Facility proton, photon, vacuum, radiation 268
  • S. Burger, B. Biskup, S. Mazzoni, M. Turner
    CERN, Geneva, Switzerland
  • B. Biskup
    Czech Technical University, Prague 6, Czech Republic
  • M. Turner
    TUG/ITP, Graz, Austria
  Beam observation systems, based on charged particles passing through a light emitting screen, are widely used and often crucial for the operation of particle accelerators as well as experimental beamlines. The AWAKE experiment, currently under construction at CERN, requires a detailed understanding of screen sensitivity and the associated accuracy of the beam size measurement. We present the measurement of relative light yield and screen resolution of seven different materials (Chromox, YAG, Alumina, Titanium, Aluminium, Aluminium and Silver coated Silicon). The Chromox and YAG samples were additionally measured with different thicknesses. The measurements were performed at the CERN's HiRadMat test facility with 440 GeV/c protons, a beam similar to the one foreseen for AWAKE. The experiment was performed in an air environment.  
poster icon Poster MOPG78 [2.795 MB]  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-MOPG78  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUPG17 Design and Beam Test Results of the Reentrant Cavity BPM for the European XFEL electronics, cavity, linac, cryomodule 356
  • C. Simon, M. Luong, O. Napoly
    CEA/DSM/IRFU, France
  • N. Baboi, D. Lipka, D. Nölle, G. Petrosyan
    DESY, Hamburg, Germany
  • R. Baldinger, B. Keil, G. Marinkovic, M. Roggli
    PSI, Villigen PSI, Switzerland
  • M. Baudrier
    CEA/DRF/IRFU, Gif-sur-Yvette, France
  • L. Maurice
    CEA/IRFU, Gif-sur-Yvette, France
  The European X-ray Free Electron Laser (E-XFEL) will use reentrant beam position monitors (BPMs) in about one quarter of the superconducting cryomodules. This BPM is composed of a radiofrequency (RF) reentrant cavity with 4 antennas and an RF signal processing electronics. Hybrid couplers, near the cryomodules, generate the analog sum and difference of the raw pickup signals coming from two pairs of opposite RF feedthroughs. The resulting sum (proportional to bunch charge) and difference signals (proportional to the product of position and charge) are then filtered, down-converted by an RF front-end (RFFE), digitized, and digitally processed on an FPGA board. The task of CEA/Saclay was to cover the design, fabrication and beam tests and deliver these reentrant cavity BPMs for the E-XFEL linac in collaboration with DESY and PSI. This paper gives an overview of the reentrant BPM sys-tem with focus on the last version of the RF front end electronics, signal processing, and overall system performance. Measurement results achieved with prototypes installed at the DESY FLASH2 linac and in the E-XFEL injector are presented.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG17  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUPG32 Blip Scanning System Power Supply Control feedback, target, impedance, software 406
  • Z. Altinbas, R.F. Lambiase, C. Theisen
    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. Dept. of Energy.
In the Brookhaven LINAC Isotope Producer (BLIP) facility, a fixed target is bombarded by proton beam to produce isotopes for medical research and cancer treatment. This bombardment process causes spot heating on the target and reduces its lifetime. To mitigate this problem, an upgrade to the beamline has been made by spreading the beam on the target in a circular pattern, which allows the target to heat more uniformly. The beam is steered in a circular pattern by a magnet with orthogonal (X and Y) windings. Each of these two windings is independently powered as part of a resonant circuit driven by a power amplifier. This paper describes the hardware platform used as well as the software implementation of the resonant circuit design and its feedback loops.
poster icon Poster TUPG32 [9.262 MB]  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG32  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUPG44 Diagnoses and Controls of Single e-Pulse Extraction at LCLS-I for the ESTB Program extraction, kicker, feedback, operation 445
  • J.C. Sheppard, T.G. Beukers, W.S. Colocho, F.-J. Decker, A.A. Lutman, B.D. McKee, T.J. Smith, M.K. Sullivan
    SLAC, Menlo Park, California, USA
  A pulsed magnet is used to kick single electron bunches into the SLAC A-line from the 120 Hz LCLS-1 bunch train. These single bunches are transported to the End Station Test Beam facility. It is mandated that extraction from the LCLS beam does not disturb the non-kicked pulses. An 8 mrad kick is required to extract a bunch; without compensation the following bunch experiences a 2 urad kick; with compensation this kick is reduced to about 0.1 urad which is well within the jitter level of about 0.3 urad. Electron and photon diagnostics were used to identify problems arising from eddy currents, beam feedback errors, and inadequate monitoring and control protocol. This paper discusses the efforts to diagnose, remedy, and control the pulse snatching.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG44  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUPG61 Stable Transmission of RF Signals and Timing Events With Accuracy at Femtoseconds laser, timing, electron, feedback 491
  • M. Liu, X.L. Dai, C.X. Yin
    SINAP, Shanghai, People's Republic of China
  Funding: Supported by the National Natural Science Foundation of China (No. 11305246) and the Youth Innovation Promotion Association CAS (No. 2016238).
We present a new design of femtosecond timing system. In the system, RF signal and timing events are transmitted synchronously in one single optical fiber with very high accuracy. Based on the theory of Michelson's interferometer, phase drift is detected with accuracy at femtoseconds. And phase compensation is accomplished in transmitter with two approaches afterwards. Moreover, the traditional event timing system is integrated into the new system to further reduce the jitter of timing triggers. The system could be applied in synchrotron light sources, free electron lasers and colliders, where distribution of highly stable timing information is required. The physics design, simulation analysis and preliminary results are demonstrated in the paper.
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG61  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUPG79 LANSCE Isotope Production Facility Emittance Measurement System emittance, diagnostics, isotope-production, hardware 548
  • J.D. Sedillo, D. Baros, J.F. O'Hara, L. Rybarcyk, R.A. Valicenti, H.A. Watkins
    LANL, Los Alamos, New Mexico, USA
  A new beam diagnostic system for emittance measurement is under development for the Isotope Production Facility (IPF) beamline located at the Los Alamos Neutron Science Center (LANSCE). This system consists of two axes; each composed of a harp and slit actuation system for measuring the emittance of 41, 72, and 100-MeV proton beam energies. System design details and project status will be discussed with installation and commissioning of this system scheduled to conclude by February 2017.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG79  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUPG80 Design and Implementation of Non-Invasive Profile Monitors for the ESS LEBT alignment, proton, vacuum, photon 551
  • C.A. Thomas, T. Galh, T.J. Grandsaert, H. Kocevar, J.H. Lee, A. Serrano, T.J. Shea
    ESS, Lund, Sweden
  We present in this paper the design and implementation of the Non-invasive Profile Monitors for the ESS LEBT. Non-invasive Profile Monitors at ESS measure the transverse profile of the high power proton beam. As such the NPM for the LEBT is not different from NPM designed for other sections of the ESS linac, however, it received the requirement to measure the position of the beam accurately with respect to the centre of the vacuum chamber, representing the reference orbit. This particular requirement led to implement a specific design to provide absolute position measurement to the system. In the following we will first describe the design and the associated functionalities, and then we will present the performance measurements of this built system, fully integrated into the control system. Finally we will discuss the performance in comparison to the initial requirements.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG80  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
TUPG82 Preliminary Measurement on Potential Luminescent Coating Material for the ESS Target Imaging Systems target, proton, detector, coupling 559
  • C.A. Thomas, M.A. Hartl, Y. Lee, T.J. Shea
    ESS, Lund, Sweden
  • E. Adli, H. Gjersdal, M.R. Jaekel, O. Rohne
    University of Oslo, Oslo, Norway
  • S. Joshi
    University College West, Trollhätan, Sweden
  We present in this paper the preliminary measurements performed on luminescent materials to be investigated and eventually coated on the ESS target wheel, the Proton Beam Window separating the end of the ESS Linac and the entrance of the ESS target area, and the ESS Dump. Among all the properties of the luminescent material required for the target imaging systems, luminescence yield and luminescent lifetime are essential for two reasons. The first one is trivial, since this material is the source for the imaging system and sets its potential performance. The lifetime is not generally of importance, unless the object is moving, or time dependence measurements are to be done. In our case, the target wheel is moving, and measurement of the beam density current may have to be performed at the 10μups scale. Thus luminescence lifetime of the coating material should be known and measured. In this paper, we present the luminescence measurements of the photo-luminescent lifetime of several materials currently under studies to be used eventually for the first beam on target.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-TUPG82  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
WEPG06 Orbit Feedforward and Feedback Applications in the Taiwan Light Source feedback, power-supply, operation, insertion 623
  • C.H. Kuo, P.C. Chiu, K.T. Hsu, K.H. Hu
    NSRRC, Hsinchu, Taiwan
  Taiwan Light Source (TLS) is a 1.5 GeV third-generation light source with circumference 120 meters. TLS is operated at 360 mA top-up injection mode. The storage ring is 6-fold symmetry with 6-meter straight sections for injection, RF cavity, and insertion devices. There are three undulators were installed in three straight sections to delivery VUV and soft X-ray for users. Beside there undulators, a conventional wiggler (W200 installed at straight sections to provide hard X-ray to serve user. Working parameters of hard X-ray sources are fixed without cause problem on operation. However, undulators should be changing its working parameters during user experiments performed. These undulator during its gap/phase changing will create orbit perturbation due to its field errors. Orbit feedback is main tool to keep orbit without change. However, some correctors setting of the orbit feedback system are easy to saturation due to large perturbation come from U90. To keep functionality of the orbit feedback system working in good condition, combines with orbit feedback and feed-forward is proposed and reported in this conference.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG06  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
WEPG08 Fast Orbit Feedback with Linux PREEMPT_RT feedback, insertion-device, cavity, insertion 630
  • Y.E. Tan
    SLSA, Clayton, Australia
  • D.J. Peake
    The University of Melbourne, Melbourne, Victoria, Australia
  • D.O. Tavares
    LNLS, Campinas, Brazil
  The fast orbit feedback system in development at the Australian Synchrotron aims to improve the stability of the electron beam by reducing the impact of insertion devices and targeting orbit perturbations at the line frequency (50 Hz, 100 Hz and 300 Hz). The system is designed to have a unity gain at a frequency greater than 300 Hz with a simple PI controller with harmonic suppressors in parallel (as was done at Elettra). With most of the system in place (position aggregation, power supplies and corrector coils) we decided to implement a PC based feedback system to test what has been installed as well as the effectiveness of the proposed control algorithms while the firmware for the FPGA based feedback processor is being developed. This paper will report on effectiveness of a feedback system built using a Linux Operating System with the PREEMPT patch running on an Intel CPU.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG08  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
WEPG10 Phase and Energy Stabilization System at the S-Dalinac electron, linac, cavity, injection 638
  • T. Bahlo, C. Burandt, L.E. Jürgensen, T. Kürzeder, N. Pietralla, J. Wissmann
    TU Darmstadt, Darmstadt, Germany
  • F. Hug
    IKP, Mainz, Germany
  The Superconducting Darmstadt Linear Accelerator S‑DALINAC is a recirculating electron accelerator with a design energy of 130 MeV operating in cw. Before entering the 30 MeV main accelerator the low energetic electron beam passes both a normal-conducting injector beamline preparing the beam's 3 GHz time structure as well as a superconducting 10 MeV injector beamline for preacceleration. Since the superconducting injector accelerates on-crest while the main accelerator accelerates off-crest the beam phase is crucial for the efficiency of the acceleration process and the minimization of the energy spread. Due to thermal drifts of the normal-conducting injector cavities this injection phase varies by about 0.2 degree over a timescale of an hour. In order to compensate for these drifts, a high level phase controller has been implemented. Additionally a low-energy scraper system has been installed between the injector and main linac in order to lock both the phase and the energy spread at the linac entrance. We will present the hardware for the phase controller, the control algorithm and the scraper setup. A report on measurements showing the effect of both systems will be given.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG10  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
WEPG15 A FPGA Based Common Platform for LCLS2 Beam Diagnostics and Controls network, timing, FPGA, hardware 650
  • J.C. Frisch, R. Claus, J.M. D'Ewart, G. Haller, R.T. Herbst, B. Hong, U. Legat, L. Ma, J.J. Olsen, B.A. Reese, R. Ruckman, L. Sapozhnikov, S.R. Smith, T. Straumann, D. Van Winkle, J.A. Vásquez, M. Weaver, E. Williams, C. Xu, A. Young
    SLAC, Menlo Park, California, USA
  Funding: work supported by Department of Energy contract DE-AC02-76SF00515
The LCLS2 is a CW superconducting LINAC driven X-ray free electron laser under construction at SLAC. The high beam rate of up to 1MHz, and ability to deliver electrons to multiple undulators and beam dumps, results in a beam diagnostics and control system that requires real time data processing in programmable logic. The SLAC Technical Innovation Directorate has developed a common hardware and firmware platform for beam instrumentation based on the ATCA crate format. The FPGAs are located on ATCA carrier cards, front ends and A-D / D-A are on AMC cards that are connected to the carriers by high speed serial JESD links. External communication is through the ATCA backplane, with interlocks and low frequency components on the ATCA RTM. This platform is used for a variety of high speed diagnostics including stripline and cavity BPMs.
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG15  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
WEPG16 The SLAC LINAC LLRF Controls Upgrade klystron, linac, timing, LLRF 654
  • D. Van Winkle, J.M. D'Ewart, J.C. Frisch, B. Hong, U. Legat, J.J. Olsen, P. Seward, J.A. Vásquez
    SLAC, Menlo Park, California, USA
  Funding: Work supported by Department of Energy contract DE-AC02-76SF00515
The low level RF control for the SLAC LINAC is being upgraded to provide improved performance and maintainability. RF control is through a high performance FPGA based DDS/DDC system built on the SLAC ATCA common platform. The klystron and modulator interlocks are being upgraded, and the interlocks are being moved into a combination of PLC logic and a fast trip system. A new solid state sub-booster amplifier will eliminate the need for the 1960s vintage high RF phase shifters and attenuators.
poster icon Poster WEPG16 [12.133 MB]  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG16  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
WEPG33 The Measurement and Controlling System of Beam Current for Weak Current Accelerator electron, target, detector, gun 697
  • J.H. Yue, Y. Li, Z.J. Ma, Y. Xie, L. Yu
    IHEP, Beijing, People's Republic of China
  For some detectors' calibration, a very weak electron current provided by accelerator is necessary. In order to control the beam current to the detector, 8 movable slits in which the position resolution of the stoppers is better than 5μm are installed along the accelerator. For the weak current measurement, 9 movable current monitors based on scintillator are installed along the beam line. These monitors can measure the very weak current, even to several electrons. The monitors can be pulled away the beam axis when the electron beam goes to the downstream.  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG33  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
WEPG39 Measurement Uncertainty Assessments of the SPIRAL2 ACCT/DCCT linac, electronics, rfq, site 712
  • S.L. Leloir, T.A. Andre, C. Jamet, G. Ledu, S. Loret, C. Potier de courcy
    GANIL, Caen, France
  Four instrumentation chains with AC and DC Current Transformers (ACCT-DCCT) will equip the lines of SPIRAL2 facility to measure the beam intensity and line transmissions. These measures are essential to tune and supervise the beam, to assure the thermal protection of the accelerator and to control that the intensities and transmissions are below the authorized limits. As such, the uncertainties of measurement chains must be taken into account in the threshold values. The electronic has been designed with high requirements of quality and dependability by following different steps; from prototyping, the qualification through an Analysis of Failure Modes and Effects Analysis (FMEA) until final fabrication. This paper presents the measurement uncertainty assessments of the ACCT/DCCT chains.  
poster icon Poster WEPG39 [0.551 MB]  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG39  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
WEPG43 A Procedure for the Characterization of Corrector Magnets storage-ring, electron, feedback, vacuum 728
  • S. Gayadeen, M.J. Furseman, G. Rehm
    DLS, Oxfordshire, United Kingdom
  At Diamond Light source, the main assumption for the Fast Orbit Feedback (FOFB) controller design is that the corrector magnets all have the same dynamic response. In this paper, a procedure to measure the frequency responses of the corrector magnets on the Diamond Storage Ring is presented and the magnet responses are measured and compared in order to assess whether this assumption is valid. The measurements are made by exciting a single corrector magnet with a sinusoidal input and measuring the resulting sinusoidal movement on the electron beam using electron Beam Position Monitors (eBPMs). The input excitation is varied from 10 Hz to 5 kHz using a 10 mA sine wave. The amplitude ratio and the phase difference between the input excitation and the beam position excitation are determined for each input frequency and the procedure is repeated for several magnets. Variations in both gain and phase across magnets are discussed in this paper and the effect of such variations on the performance of the FOFB controller performance is determined.  
poster icon Poster WEPG43 [1.137 MB]  
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG43  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
WEPG74 Bridging the Gap; Updating LANSCE Digitizers emittance, linac, distributed, data-acquisition 822
  • D. Baros, J.D. Sedillo, H.A. Watkins
    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 upgrading equipment that is used to digitize transverse beam profile measurements. Emittance measurements were originally digitized using legacy equipment, known as RICE (Remote Indication and Control Equipment). This required 38 RICE modules distributed along the half-mile long accelerator simultaneously recording 4 channels each to populate the 76 data points needed to create a single emittance profile. The system now uses a National Instruments cRIO controller to digitize the entire profile in a single chassis. Details of the hardware selection and performance of the system for different timing structures are presented.
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG74  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
WEPG76 Status of the Two-Dimensional Synchrotron Radiation Interferometer at PETRA III emittance, diagnostics, radiation, synchrotron 829
  • A.I. Novokshonov, A. Potylitsyn
    TPU, Tomsk, Russia
  • G. Kube, M. Pelzer, G. Priebe
    DESY, Hamburg, Germany
  Synchrotron radiation based emittance diagnostics at modern 3rd generation light sources is mainly based on beam profile imaging in the X-ray region in order to overcome the resolution limit imposed by diffraction. A possibility to circumvent this limitation is to probe the spatial coherence with a double-slit interferometer in the optical spectral region [*]. The light source PETRA III at DESY is using this type of interferometer since several years in order to resolve vertical emittances of about 10 pm.rad. The device is set up behind a 30m long optical beamline, connecting the accelerator tunnel and the optical hutch. In order to increase the measurement stability, a much shorter optical beamline with reduced number of optical elements was recently commissioned. At the end of the beamline, a two-dimensional interferometer was installed which allows to deduce transverse emittances in both planes simultaneously. This contribution summarizes the status of beamline and interferometer commissioning together with model calculations in order to investigate systematically the measurement accuracy.
*T. Mitsuhashi, "Twelve Years of SR Monitor Development", 2004 Beam Instrumentation Workshop, 2014, pp. 5-11.
DOI • reference for this paper ※ DOI:10.18429/JACoW-IBIC2016-WEPG76  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)