Keyword: controls
Paper Title Other Keywords Page
MOODN3 Advanced Bent Crystal Collimation Studies at the Tevatron (T-980) collimation, collider, simulation, beam-losses 73
 
  • V.V. Zvoda, J. Annala, R.A. Carrigan, A.I. Drozhdin, T.R. Johnson, S. Kwan, N.V. Mokhov, A. Prosser, R.E. Reilly, R. Rivera, V.D. Shiltsev, D.A. Still, L. Uplegger, J.R. Zagel
    Fermilab, Batavia, USA
  • E. Bagli, V. Guidi, A. Mazzolari
    INFN-Ferrara, Ferrara, Italy
  • Y.A. Chesnokov, I.A. Yazynin
    IHEP Protvino, Protvino, Moscow Region, Russia
  • Yu.M. Ivanov
    PNPI, Gatchina, Leningrad District, Russia
 
  Funding: * Work is supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy through the US LHC Accelerator Research Program (LARP).
The T-980 bent crystal collimation experiment at the Tevatron has recently acquired substantial enhancements. First, two new crystals - a 16-strip one manufactured and characterized by the INFN Ferrara group and a quasi-mosaic crystal manufactured and characterized by the PNPI group. Second, a two plane telescope with 3 high-resolution pixel detectors per plane along with corresponding mechanics, electronics, control and software has been manufactured, tested and installed in the E0 crystal region. The purpose of the pixel telescope is to measure and image channeled (CH), volume-reflected (VR) and multiple volume-reflected (MVR) beam profiles produced by bent crystals. Third, an ORIGIN-based system has been developed for thorough analysis of experimental and simulation data. Results of analysis are presented for different types of crystals used from 2005 to present for channeling and volume reflection including pioneering tests of two-plane crystal collimation at the collider, all in comparison with detailed simulations.
 
slides icon Slides MOODN3 [1.052 MB]  
 
MOP037 Muon Ionization Cooling Experiment: Controls and Monitoring monitoring, EPICS, emittance, target 166
 
  • P.M. Hanlet
    IIT, Chicago, Illinois, USA
 
  Funding: NSF
The Muon Ionization Cooling Experiment (MICE) is a demonstration experiment to prove the viability of cooling a beam of muons for use in a Neutrino Factory and Muon Collider. The MICE cooling channel is a section of a modified Study II cooling channel which will provide a 10% reduction in beam emittance. In order to ensure a reliable measurement, we intend to measure the beam emittance before and after the cooling channel at the level of 1%, or an absolute measurement of 0.001. This renders MICE as a precision experiment which requires strict controls and monitoring of all experimental parameters in order to control systematic errors. The MICE Controls and Monitoring system is based on EPICS and integrates with the DAQ, detector, environment, and data monitoring systems. A description of this system, its implementation, and performance during recent muon beam data collection will be discussed.
 
 
MOP060 Wedge Absorber Design and Simulation for MICE Step IV emittance, simulation, lattice, scattering 220
 
  • C.T. Rogers
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
  • L. Coney, G.G. Hanson
    UCR, Riverside, California, USA
  • P. Snopok
    IIT, Chicago, Illinois, USA
 
  Funding: Work is supported by the Science and Technology Facilities Council, the U.S. Department of Energy and the U.S. National Science Foundation.
In the Muon Ionization Cooling Experiment (MICE), muons are cooled by passing through material, then through RF cavities to compensate for the energy loss; which reduces the transverse emittance. It is planned to demonstrate longitudinal emittance reduction via emittance exchange in MICE by using a solid wedge absorber in Step IV. Based on the outcome of previous studies, the shape and material of the wedge were chosen. We address here further simulation efforts for the absorber of choice as well as engineering considerations in connection with the absorber support design.
 
 
MOP107 Status of Dielectric-Lined Two-Channel Rectangular High Transformer Ratio Accelerator Structure Experiment acceleration, wakefield, electron, status 298
 
  • S.V. Shchelkunov, M.A. LaPointe
    Yale University, Beam Physics Laboratory, New Haven, Connecticut, USA
  • M.E. Conde, W. Gai, J.G. Power, Z.M. Yusof
    ANL, Argonne, USA
  • J.L. Hirshfield
    Omega-P, Inc., New Haven, Connecticut, USA
  • T.C. Marshall
    Columbia University, New York, USA
  • D. Mihalcea
    Northern Illinois University, DeKalb, Illinois, USA
  • G.V. Sotnikov
    NSC/KIPT, Kharkov, Ukraine
 
  Funding: This work is supported by DoE, Office of High Energy Physics
Recent tests of a two-channel rectangular dielectric lined accelerator structure are described; comparison with theory and related issues are presented. The structure (with channel width ratio 6:1) is designed to have a maximum transformer ratio of ~12.5:1. It operates mainly in the LSM31 mode (~ 30GHz). The dielectric liner is cordierite (dielectric constant ~4.76). The acceleration gradient is 1.2 MV/m for each 10nC of the drive bunch for the first acceleration peak of the wakefield, and 0.92 MV/m for the second peak. The structure is installed into the AWA beam-line (Argonne National Lab) and is excited by a single 10-50nC, 14MeV drive bunch. Both the drive bunch and a delayed witness bunch are produced at the same photocathode. This is the first experiment to test a two-channel dielectric rectangular wakefield device where the accelerated bunch may be continuously energized by the drive bunch. The immediate experimental objective is to observe the energy gain and spread, and thereby draw conclusions from the experimental results and the theory model predictions. The observed energy change of the test bunch might be well explained*.
* G. V. Sotnikov, et al., Advanced Accelerator Concepts: 13th Workshop, Carl B. Schroeder, Wim Leemans and Eric Esarey, editors, AIP Conf. Proc. 1086), pp. 415–420 (AIP, New York, 2009).
 
 
MOP119 The Dielectric Wakefield Accelerating Structure wakefield, plasma, simulation, electron 319
 
  • A. Kanareykin, S.P. Antipov, J.B. Butler, C.-J. Jing, P. Schoessow
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • W. Gai
    ANL, Argonne, USA
 
  Funding: US Department of Energy
We report here on the development of THz diamond wakefield structures produced using Chemical Vapor Deposition (CVD) technology*. The diamond structures would be used in a THz generation experiment at the new FACET facility at SLAC. We consider a dielectric based accelerating structure to study of the physical limitations encountered driving >GV/m wakefields in the cylindrical and planar geometries of a dielectric wakefield accelerator (DWA). In a DWA, an ultrashort drive bunch traverses the evacuated central region of the structure, creating Cherenkov wakefields in the dielectric to accelerate a witness bunch. A diamond-based DWA structure will allow a sustained accelerating gradient exceeding breakdown threshold demonstrated with the FFTB experiments**. The electrical and mechanical properties of diamond make it an ideal candidate material for use in dielectric rf structures: high breakdown voltage, extremely low dielectric losses and the highest thermoconductive coefficient available for removing waste heat from the device.
*R. J. Barker et al., Modern Microwave and Millimeter-Wave Power Electronics, IEEE Press/Wiley-Interscience, Piscataway NJ 2005, Chapter 7
**M.C. Thompson et al. Phys. Rev.Lett.100:214801, 2008.
 
 
MOP123 Colliding Pulse Injection Control in a Laser-Plasma Accelerator laser, plasma, injection, collider 325
 
  • C.G.R. Geddes, M. Chen, E. Esarey, W. Leemans, N.H. Matlis, D.E. Mittelberger, K. Nakamura, G.R.D. Plateau, C.B. Schroeder, C. Tóth
    LBNL, Berkeley, California, USA
  • D.L. Bruhwiler, J.R. Cary, E. Cormier-Michel, B.M. Cowan
    Tech-X, Boulder, Colorado, USA
 
  Funding: This work is supported by the U.S. Department of Energy, National Nuclear Security Administration, NA-22, and in part by the Office of Science under Contract No. DE-AC02-05CH11231.
Control of injection into a high gradient laser-plasma accelerator is presented using the beat between two ’colliding’ laser pulses to kick electrons into the plasma wake accelerating phase. Stable intersection and performance over hours of operation were obtained using active pointing control. Dependence of injector performance on laser and plasma parameters were characterized in coordination with simulations. By scanning the intersection point of the lasers, the injection position was controlled, mapping the acceleration length. Laser modifications to extend acceleration length are discussed towards production of tunable stable electron bunches as needed for applications including Thomson gamma sources and high energy colliders.
 
 
MOP165 Bringing Accelerator Models to the Control System Studio EPICS, optics, booster, status 403
 
  • N. Malitsky, K. Shroff
    BNL, Upton, Long Island, New York, USA
  • C. Xiaomeng
    Stony Brook University, Stony Brook, USA
 
  This paper is the next logical step in the evolution of the new EPICS-based high-level accelerator application environment. The project presents the connection of its middle layers servers with the new Eclipse-based operational toolkit, Control System Studio. The approach is illustrated by the implementation of the Model Independent Analysis application involving three key servers: Machine, Online Model, and Virtual Accelerator.  
 
MOP166 Comissioning of a BPM system for the LNLS Booster to Storage Ring Transfer Line injection, booster, monitoring, storage-ring 405
 
  • F.H. Cardoso, S.R. Marques, X.R. Resende
    LNLS, Campinas, Brazil
 
  In order to increase the number of diagnostics and make possible studies of beam position effects in the injection efficiency, a beam position monitoring system was designed to equip the BTS (booster to storage ring) transfer line employing the long striplines BPMs. The log-ratio technique was applied using a commercial electronics module (LR-BPM) from Bergoz Instrumentation. Currently the system is integrated to the LNLS control system, database and ready to be used routinely during the injections. This work describes the system topology, details about the hardware and software, bench tests and measurements performed with electron beam. Future plans to improve the injection efficiency will also be presented.  
 
MOP177 Design and Cold Test of Re-entrant Cavity BPM for HLS cavity, coupling, linac, pick-up 420
 
  • Q. Luo, Q.K. Jia, B.G. Sun, Z.R. Zhou
    USTC/NSRL, Hefei, Anhui, People's Republic of China
 
  Funding: Supported by Natural Science Foundation of China, National 985 Project, China Postdoctoral Science Foundation and the Fundamental Research Funds for the Central Universities
An S-band cavity BPM is designed for a new injector in National Synchrotron Radiation Laboratory. A re-entrant position cavity is tuned to TM110 mode as position cavity. Theoretical resolution of the BPM is 31 nm. A prototype cavity BPM system is manufactured for cold test. Wire scanning method is used to calibrate the BPM and estimate the performance of the on-line BPM system. Cold test results showed that position resolution of prototype BPM is better than 3 μm. Cross-talk has been detected during the cold test. Racetrack cavity can be used to suppress cross-talk. Ignoring nonlinear effect, transformation matrix is a way to correct cross-talk.
 
 
MOP183 First Measurements of a New Beam Position Processor on Real Beam at Taiwan Light Source brilliance, injection, betatron, storage-ring 429
 
  • P. Leban, A. Košiček
    I-Tech, Solkan, Slovenia
  • P.C. Chiu, K.T. Hsu, K.H. Hu, C.H. Kuo
    NSRRC, Hsinchu, Taiwan
 
  Libera Electron, Libera Brilliance and Libera Brilliance+ compose the electron beam position processors product family, which covers the needs of wide variety of the circular light source machines. The instruments deliver unprecedented possibilities for either building powerful single station solutions or architecting complex feedback systems. Compared to its predecessors (Libera Electron and Libera Briliance), the latest member of the family Libera Brilliance+ allows even more extensive machine physics studies to be conducted due to large data buffers and the new true turn-by-turn position calculation. It offers a large playground for custom- written applications with VirtexTM 5 and COM Express Basic module with Intel Atom N270 (x86) inside. First field tests of the new product were performed on real beam at Taiwan Light Source (TLS). The test setup, measurements and results are discussed in the paper.  
 
MOP196 A Modular Architecture for Accelerator Instrumentation feedback, instrumentation, target, low-level-rf 459
 
  • J.H. DeLong
    BNL, Upton, Long Island, New York, USA
 
  Funding: US Department of Energy
With accelerated schedules and finite resources the development of a common open source platform for accelerator instrumentation is required. This effort has led to the development of a flexible architecture with clearly defined interfaces. The resulting platform is currently used to implement fast orbit feedback as well as the Beam Position monitors for NSLS-II. The design includes an embedded processor, digital signal processing resources and communications interfaces to controls, the timing system and other devices distributed throughout the accelerator complex. This new architecture promotes customization and design re-use and is presented as an Open Source Hardware development project.
 
 
MOP197 RHIC Stochastic Cooling Motion Control pick-up, kicker, cavity, alignment 462
 
  • D.M. Gassner, S. Bellavia, J.M. Brennan, L. DeSanto, W. Fu, C.J. Liaw, R.H. Olsen
    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.
Relativistic Heavy Ion Collider (RHIC) beams are subject to Intra-Beam Scattering (IBS) that causes an emittance growth in all three-phase space planes. The only way to increase integrated luminosity is to counteract IBS with cooling during RHIC stores. A stochastic cooling system [1] for this purpose has been developed, it includes moveable pick-ups and kickers in the collider that require precise motion control mechanics, drives and controllers. Since these moving parts can limit the beam path aperture, accuracy and reliability is important. Servo, stepper, and DC motors are used to provide actuation solutions for position control. The choice of motion stage, drive motor type, and controls are based on needs defined by the variety of mechanical specifications, the unique performance requirements, and the special needs required for remote operations in an accelerator environment. In this report we will describe the remote motion control related beam line hardware, position transducers, rack electronics, and software developed for the RHIC stochastic cooling pick-ups and kickers.
 
 
MOP198 BPM Inputs to Physics Applications at NSLS-II feedback, EPICS, alignment, diagnostics 465
 
  • Y. Hu, L.R. Dalesio, J.H. DeLong, K. Ha, J. Mead, I. Pinayev, G. Shen, O. Singh, Y. Tian, K. Vetter, L.-H. Yu
    BNL, Upton, Long Island, New York, USA
 
  A new BPM (Beam Position Monitor) electronics is under development and in good progress at NSLS-II. This in-house BPM receiver with many new features is comparable to commercial solution. BPM data for fast orbit feedback (FOFB) is one of the most important physics applications. The procedure to use BPM for FOFB is introduced firstly. Then, different BPM data flows associated with different physics requirements and applications are discussed. And control implementation of BPM system for physics applications is presented.  
 
MOP203 RHIC Spin Flipper AC Dipole Controller dipole, feedback, LLRF, heavy-ion 474
 
  • P. Oddo, M. Bai, W.C. Dawson, D.M. Gassner, M. Harvey, T. Hayes, K. Mernick, M.G. Minty, T. Roser, F. Severino, K.S. Smith
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under contract DE-AC02-98CH10886 with the U.S. Department of Energy and RIKEN, Japan.
The RHIC Spin Flipper's five high-Q AC dipoles which are driven by a swept frequency waveform require precise control of phase and amplitude during the sweep. This control is achieved using FPGA based feedback controllers. Multiple feedback loops are used to control and dynamically tune the magnets. The current implementation and results will be presented.
 
 
MOP208 Baseline Suppression Problems for High Precision Measurements Using Optical Beam Profile Monitors. background, brightness, radiation, monitoring 486
 
  • P. Thieberger, D.M. Gassner, J.W. Glenn, M.G. Minty, C.M. Zimmer
    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 use of fluorescent screens for beam profile monitors provides a simple and widely used way to obtain detailed two dimensional intensity maps. For high precision measurements many possible error contributions need to be considered that have to do with properties of the fluorescent screens and of the CCDs. Saturation effects, reflections within and outside the screen, non-linearities, radiation damage, etc are often mentioned. Here we concentrate on an error source less commonly described, namely erroneous baseline subtraction, which is particularly important when fitting projected images. We show computer simulations as well as measurement results having remarkable sensitivity of the fitted profile widths to even partial suppression of the profile baseline data, which often arises from large pixel-to-pixel variations at low intensity levels. Such inadvertent baseline data suppression is very easy to miss as it is usually not obvious when inspecting projected profiles. In this report we illustrate this effect and discuss possible algorithms to automate the detection of this problem as well as some possible corrective measures.
 
 
MOP211 NSLS-II RF Beam Position Monitor feedback, injection, EPICS, storage-ring 495
 
  • K. Vetter, J.H. DeLong, A.J. Della Penna, K.M. Ha, Y. Hu, B.N. Kosciuk, J. Mead, I. Pinayev, O. Singh, Y. Tian
    BNL, Upton, Long Island, New York, USA
  • G.J. Portmann
    LBNL, Berkeley, California, USA
  • J.J. Sebek
    SLAC, Menlo Park, California, USA
 
  Funding: Work supported by the U.S. DOE under contract No. DE-AC02-98CH10886.
An internal R&D program has been undertaken at BNL to develop a sub-micron RF Beam Position Monitor (BPM) for the NSLS-II 3rd generation light source that is currently under construction. The BPM R&D program started in August 2009. Successful beam tests were conducted 15 months from the start of the program. The NSLS-II RF BPM has been designed to meet all requirements for the NSLS-II Injection system and Storage Ring. Housing of the RF BPMs in ±0.1C thermally controlled racks provide sub-micron stabilization without active correction. An active pilot-tone has been incorporated to aid long-term (8hr min) stabilization to 200nm RMS.
 
 
MOP212 Quadrupole Beam-Based Alignment in the RHIC Interaction Regions quadrupole, proton, alignment, focusing 498
 
  • J.M. Ziegler
    BNL, Upton, Long Island, New York, USA
  • T. Satogata
    JLAB, Newport News, Virginia, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
Continued beam-based alignment (BBA) efforts have provided significant benefit to both heavy ion and polarized proton operations at RHIC. Recent studies demonstrated previously unknown systematic beam position monitor (BPM) offset errors and produced accurate measurements of individual BPM offsets in the experiment interaction regions. Here we describe the algorithm used to collect and analyze data during the 2010 and early 2011 RHIC runs and the results of these measurements.
 
 
MOP218 High Level Software for 4.8 Ghz LHC Schottky System proton, ion, betatron, status 507
 
  • J. Cai, E.S.M. McCrory, R.J. Pasquinelli
    Fermilab, Batavia, USA
  • M. Favier, O.R. Jones
    CERN, Geneva, Switzerland
  • A. Jansson
    ESS, Lund, Sweden
  • T.E. Lahey
    SLAC, Menlo Park, California, USA
 
  A high level software package has been developed for a 4.8GHz Schottky system installed in the LHC at CERN. It has two main components. The first is a monitor application continuously running on a dedicated server as a daemon process to acquire the FFT traces, perform data analysis, publish results and do archiving. The second is a graphical user interface to display the FFT traces and various measurement results. It also allows the end user to change the settings for the front-end electronics such as the local oscillators, bunch selector, amplifier gains etc. Data analysis with curve fitting poses a big challenge due to the strong coherent signals that are often observed superimposed onto the Schottky sidebands. A method has been successfully created to remove the coherent spikes to enable curve fitting on the underlying signals, with the ultimate aim of providing reliable tune, momentum spread, chromaticity and emittance measurements for LHC beams with no external excitation.  
 
MOP221 An Application for Tunes and Coupling Evaluation From Turn-by-Turn Data at the Fermilab Booster coupling, booster, resonance, optics 516
 
  • W.L. Marsh, Y. Alexahin, E. Gianfelice-Wendt
    Fermilab, Batavia, USA
 
  Funding: Work supported by Fermi Research Alliance, LLC under DE-AC02-07CH11359 with the U.S. DOE.
A console application using the phasing of Turn-by-Turn signals from the different BPMs has been tested at the Fermilab Booster. This techinique allows the on-line detection of the beam tunes during the fast Booster ramp in conditions where other algorithms were unsuccessful. The application has been recently expanded to include the computation of the linear coupling coefficients. Algorithm and measurement results are presented.
 
 
MOP222 Operational Use of Ionization Profile Monitors in the Fermilab Main Injector antiproton, injection, proton, vacuum 519
 
  • D.K. Morris, P. Adamson, D. Capista, I. Kourbanis, T. Meyer, K. Seiya, D. Slimmer, M.-J. Yang, J.R. Zagel
    Fermilab, Batavia, USA
 
  Funding: Operated by the Fermi Research Alliance, LLC under contract No. DE-AC02-07CH11359 with the United States Department of Energy.
Ionization profile monitors (IPMs) are used in the Fermilab Main Injector (MI) for injection lattice matching and to measure transverse emittance of the beam during acceleration. The IPMs provide a periodic, non-destructive means for emittance measurements where other techniques are not applicable. As Fermilab is refocusing its attention on the intensity frontier, non-intercepting diagnostics such as IPMs are expected to become even more important. This paper gives an overview of the operational use of IPMs for emittance measurements and injection lattice matching measurements at Fermilab, and summarizes the future plans.
 
 
MOP226 Transverse Emittance and Phase Space Program Developed for Use at the Fermilab A0 Photoinjector emittance, vacuum, background, cavity 528
 
  • R.M. Thurman-Keup, A.S. Johnson, A.H. Lumpkin, J. Ruan
    Fermilab, Batavia, USA
 
  Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
The Fermilab A0 Photoinjector is a 16MeV high intensity, high brightness electron Linac developed for advanced accelerator R&D. One of the key parameters for the electron beam is the transverse beam emittance. Here we report on a newly developed MATLAB based GUI program used for transverse emittance measurements using the multi-slit technique. This program combines the image acquisition and post-processing tools for determining the transverse phase space parameters with uncertainties.
 
 
MOP232 LANSCE-R Wire-Scanner Analog Frontend Electronics (AFE) shielding, coupling, electromagnetic-fields, monitoring 542
 
  • M.E. Gruchalla
    URS, Albuquerque, New Mexico, USA
  • P. Chacon, J.D. Gilpatrick, D. Martinez, J.D. Sedillo
    LANL, Los Alamos, New Mexico, USA
 
  Funding: U.S. Department of Energy.
A new AFE is being developed for the new LANSCE-R wire-scanner systems. The new AFE is implemented in a National Instruments cRIO module installed a BiRa 4U BiRIO cRIO chassis specifically designed to accommodate the cRIO crate and all the wire-scanner interface, control and motor-drive electronics. A single AFE module provides interface to both X and Y wire sensors using true DC coupled transimpedance amplifiers providing collection of the wire charge signals, real-time wire integrity verification using the normal data-acquisition system, and wire bias of 0V to ±50V. The AFE system is designed to accommodate comparatively long macropulses (>1ms) with high PRF (>120Hz) without the need to provide timing signals. The basic AFE bandwidth is flat from true DC to 50kHz with a true first-order pole at 50kHz. Numeric integration in the cRIO FPGA provides real-time pulse-to-pulse numeric integration of the AFE signal to compute the total charge collected in each macropulse. This method of charge collection eliminates the need to provide synchronization signals to the wire-scanner AFE while providing the capability to accurately record the charge from long macropulses at high PRF.
 
 
MOP233 LANSCE-R Wire-scanner System EPICS, diagnostics 545
 
  • M.E. Gruchalla
    URS, Albuquerque, New Mexico, USA
  • P. Chacon, J.D. Gilpatrick, D. Martinez, S. Rodriguez Esparza, F.D. Sattler, J.D. Sedillo, B.G. Smith
    LANL, Los Alamos, New Mexico, USA
 
  Funding: US Department of Energy
The National Instruments cRIO platform is used for the new LANSCE-R wire-scanner systems. All wire-scanner electronics are integrated into a single BiRa BiRIO 4U cRIO chassis specifically designed for the cRIO crate and all interface electronics. The BiRIO chassis, actuator and LabVIEW VIs provide a complete wire-scanner system integrated with EPICS. The new wire-scanner chassis includes an 8-slot cRIO crate with Virtex-5 LX 110 FPGA and Power-PC real-time controller, the LANL-developed cRIO 2-axis wire-sensor analog interface module (AFE), NI9222 cRIO 4-channel 16-bit digitizer, cRIO resolver demodulator, cRIO event receiver, front-panel touch panel display, motor driver, and all necessary software, interface wiring, connectors and ancillary components. This wire-scanner system provides a complete, turn-key, 2-axis wire-scanner system including 2-channel low-noise sense-wire interface with variable DC wire bias and wire-integrity monitor, 16-bit signal digitizers, actuator motor drive and control, actuator position sensing, limit-switch interfaces, event receiver, LabVIEW and EPICS interface, and both remote operation and full stand-alone operation using the touch panel.
 
 
MOP234 Beam Position and Phase Monitors for the LANSCE Linac linac, neutron, monitoring, instrumentation 548
 
  • R.C. McCrady, J.D. Gilpatrick, J.F. Power
    LANL, Los Alamos, New Mexico, USA
 
  Funding: This work is supported by the US Department of Energy under contract DE-AC52-06NA25396
New beam-position and phase monitors are under development for the linac at the Los Alamos Neutron Science Center. Transducers have been designed and are being fabricated. We are considering many options for the electronic instrumentation to process the signals and provide position and phase data with the necessary precision and flexibility to serve the various required functions. We’ll present the requirements of the system and the various options under consideration for instrumentation along with the advantages and shortcomings of these options.
 
 
MOP236 First Test Results of the New LANSCE Wire Scanner diagnostics, background, coupling, target 554
 
  • J.D. Sedillo, J.D. Gilpatrick, F. Gonzales, V. Kutac, D. Martinez
    LANL, Los Alamos, New Mexico, USA
  • M.E. Gruchalla
    URS, Albuquerque, New Mexico, USA
 
  Funding: United States Department of Energy.
The Beam Diagnostics and Instrumentation Team at Los Alamos National Laboratory’s LANSCE facility is presently developing a new and improved wire scanner diagnostics system controlled by National Instrument’s cRIO platform. This report describes the current state of development of the control system along with the results gathered from the latest actuator motion performance and accelerator beam data acquisition tests.
 
 
MOP247 Quick Setup of Unit Test For Accelerator Controls System kicker, heavy-ion, status, collider 574
 
  • W. Fu, T. D'Ottavio, D.M. Gassner, J. Morris, S. Nemesure
    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.
Testing a single hardware unit of an accelerator control system often requires the setup of a graphical user interface. Developing a dedicated application for a specific hardware unit test could be time consuming and the application may become obsolete after the unit tests. This paper documents a methodology for quick design and setup of an interface focused on performing unit tests of accelerator equipment with minimum programming work. The method has three components. The first is a generic accelerator device object (ADO) manager which can be used to setup, store, and log testing controls parameters for any unit testing system. The second involves the design of a TAPE (Tool for Automated Procedure Execution) sequence file that specifies and implements all testing and control logic. The third is the design of a PET (parameter editing tool) page that provides the unit tester with all the necessary control parameters required for testing. This approach has been used for testing the horizontal plane of the Stochastic Cooling Motion Control System at RHIC.
 
 
MOP248 Automating Power Supply Checkout power-supply, heavy-ion, collider, ion 577
 
  • J.S. Laster, D. Bruno, T. D'Ottavio, J. Drozd, G.J. Marr, C. Mi
    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.
Power Supply checkout is a necessary, pre-beam, time-critical function. At odds are the desire to decrease the amount of time to perform the checkout while at the same time maximizing the number and types of checks that can be performed and analyzing the results quickly (in case any problems exist that must be addressed). Controls and Power Supply Group personnel have worked together to develop tools to accomplish these goals. Power Supply checkouts are now accomplished in a time-frame of hours rather than days, reducing the number of person-hours needed to accomplish the checkout and making the system available more quickly for beam development.
 
 
MOP249 Improved Alarm Tracking for Better Accountability diagnostics, feedback, status, collider 579
 
  • S. Nemesure, T. D'Ottavio, L.R. Hammons, P.F. Ingrassia, N.A. Kling, G.J. Marr, T.C. Shrey
    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.
An alarm system is a vital component of any accelerator, as it provides a warning that some element of the system is not functioning properly. The severity and age of the alarm may sometimes signify whether urgent or deferred attention is required. For example, older alarms may inadvertently be given a lower priority if an assumption is made that someone else is already investigating it, whereas those that are more current may indicate the need for an immediate response. The alarm history also provides valuable information regarding the functionality of the overall system, thus careful tracking of these data is likely to improve response time and remove uncertainty about the current status. Since one goal of every alarm display is to be free of alarms, a clear and concise presentation of an alarm along with useful historic annotations can help the end user address the warning more quickly. By defining a discrete set of very specific alarm states and by utilizing database resources to maintain a complete and easily accessible alarm history, we anticipate a decrease in down time due to more efficient operator response and management of alarms.
 
 
MOP250 NSLS-II High Level Application Infrastructure and Client API Design EPICS, quadrupole, emittance, monitoring 582
 
  • G. Shen, K. Shroff, L. Yang
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work performed under auspices of the U.S. Department of Energy under Contract No. DE-AC02-98CH10886 with Brookhaven Science Associates, LLC.
The beam commissioning software framework of NSLS-II project adopts a client/server based architecture to replace the more traditional monolithic high level application approach. It is an open structure platform, and we try to provide a narrow API set for client application. With this narrow API, existing applications developed in different language under different architecture could be ported to our platform with small modification. This paper describes a detailed client API design, and latest progress.
 
 
MOP252 Server Development for NSLS-II Physics Applications and Performance Analysis EPICS, emittance, synchrotron, synchrotron-radiation 585
 
  • G. Shen, M.R. Kraimer
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work performed under auspices of the U.S. Department of Energy under Contract No. DE-AC02-98CH10886 with Brookhaven Science Associates, LLC.
The beam commissioning software framework of NSLS-II project adopts a client/server based architecture to replace the more traditional monolithic high level application approach. The server development is ongoing, and adopts a sourceforge open project so-called epics-pvdata, which consists of pvData, pvAccess, pvEngine, and pvService. Some services have being demonstrated as one service under pvService module such as itemFinder service, gather service, and lattice manager, and each service runs as one standalone server using pvData to store in-memory transient data, pvService to transfer data over network, and pvEngine as service engine. This paper describes a detailed development, latest progress, and performance analysis.
 
 
MOP256 Upgrading the Data Acquisition and Control System of the LANSCE LINAC linac, EPICS, proton, neutron 588
 
  • D. Baros
    LANL, Los Alamos, New Mexico, USA
 
  Funding: This work has benefited from the use of the LANSCE at LANL. This facility is funded by the US DOE and operated by LANS for NSSA under Contract DE-AC52-06NA25396.
Los Alamos National Laboratory LANL is in the process of upgrading the control system for the Los Alamos Neutron Science Center (LANSCE) linear accelerator. The 38 year-old data acquisition and control equipment is being replaced with COTS hardware. An overview of the current system requirements and how the National Instruments cRIO system meets these requirements will be given, as well as an update on the installation and operation of a prototype system in the LANSCE LINAC.
LANL Release Number: LA-UR 10-06605
 
 
MOP257 High Power RF Distribution and Control for Multi-Cavity Cryomodule Testing cryomodule, cavity, linac, klystron 591
 
  • Y.W. Kang, M. Broyles, M.T. Crofford, X. Geng, S.-H. Kim, S.W. Lee, C.L. Phibbs, K.R. Shin, W.H. Strong
    ORNL, Oak Ridge, Tennessee, USA
 
  Funding: This work was supported by SNS through UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. DOE.
The SNS has been successfully operating 81 superconducting six-cell cavities in 23 cryomodules in its linac to achieve the goals in beam power and energy. For near-term production of spare cryomodules and the upcoming power upgrade project that will need 36 additional cavities in 9 cryomodules, high RF power testing and qualification of the cavities is required in the RF test facility. Simultaneously powering all the cavities in a cryomodule is considered desirable for robust conditioning and studying of cavity field emission since certain cavities exhibit field emissions that could be mutually coupled. A four-way variable output power waveguide splitting system is being prepared for testing cryomodules with up to four cavities. The splitting system is fed by an 805 MHz, 5 MW peak power pulsed klystron. The power output at each arm can be adjusted in both amplitude and phase to wide ranges of values using two mechanical waveguide phase shifters that form a vector modulator. The system control is implemented in the EPICS environment similar to the main accelerator controls. The work performed on the design, integration, operation, and test of the system are presented.
 
 
MOP261 The CEBAF Element Database lattice, linac, background, alignment 594
 
  • T. L. Larrieu, M.E. Joyce, C.J. Slominski
    JLAB, Newport News, Virginia, USA
 
  Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
With inauguration of the CEBAF Element Database(CED) in Fall 2010, Jefferson Lab computer scientists have taken a first step toward the eventual goal of a model-driven accelerator. Once fully populated, the database will be the primary repository of information used for everything from generating lattice decks to booting iocs to building controls screens. A requirement influencing the CED design is that it provide access to not only present, but also future, and eventually past, configurations of the accelerator. To accomplish this, an introspective database schema was designed that allows new elements, types, and properties to be defined on-the-fly with no changes to table structure. Used in conjunction with Oracle Workspace Manager, it allows users to query data from any time in the database history with the same tools used to query the present configuration. Users can also check-out workspaces to use as staging areas for upcoming machine configurations. All Access to the CED is through a well-documented API that is translated automatically from original C++ into native libraries for script languages such as perl, php, and TCL making access to the CED easy and ubiquitous.
The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.
 
 
MOP263 Fast Orbit Feedback System for the LNLS Storage Ring feedback, storage-ring, synchrotron, injection 597
 
  • L. Sanfelici, F.H. Cardoso, D.D. Felix Ferreira, S.R. Marques, D.O. Tavares
    LNLS, Campinas, Brazil
 
  The Brazilian Synchrotron Light Laboratory (LNLS) is based on a 1.37 GeV storage ring, previously operated by means of a Slow Orbit Feedback System at a maximum rate of 1 correction every 3 seconds. Since photon flux stability is a key issue for light source users, a faster control system was envisaged to provide better beam stability. This work presents an overview of the hardware architecture and the preliminary results achieved with the implementation of a Fast Orbit Feedback System using commercial hardware. BPM signals are acquired in a distributed topology and sent through a deterministic EtherCAT network to a PXI controller, responsible for applying the SVD-based correction matrix multiplication and communicating with the accelerator control system; the calculated current setpoints are sent to the correctors’ power supplies through a second EtherCAT network. FPGA-based acquisition and actuation chassis perform pre-filtering and control on the digitized input and output signals, respectively.  
 
MOP268 RHIC 10 Hz Global Orbit Feedback System feedback, power-supply, dipole, luminosity 609
 
  • R.J. Michnoff, L. Arnold, C. Carboni, P. Cerniglia, A.J. Curcio, L. DeSanto, C. Folz, C. Ho, L.T. Hoff, R.L. Hulsart, R. Karl, C. Liu, Y. Luo, W.W. MacKay, G.J. Mahler, W. Meng, K. Mernick, M.G. Minty, C. Montag, R.H. Olsen, J. Piacentino, P. Popken, R. Przybylinski, V. Ptitsyn, J. Ritter, R.F. Schoenfeld, P. Thieberger, J.E. Tuozzolo, A. Weston, J. White, P. Ziminski, P. Zimmerman
    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.
Vibrations of the cryogenic triplet magnets at the Relativistic Heavy Ion Collider (RHIC) are suspected to be causing the beam perturbations observed at frequencies around 10 Hz. Several solutions to counteract the effect have been considered in the past, including reinforcing the magnet base support assembly, a mechanical servo feedback system, and a local beam feedback system at each of the two experimental areas. However, implementation of the mechanical solutions would be expensive, and the local feedback system was insufficient since perturbation amplitudes outside the experimental areas were still problematic. A global 10 Hz orbit feedback system is currently under development at RHIC consisting of 36 beam position monitors (BPMs) and 12 small dedicated dipole corrector magnets in each of the two counter-rotating rings. A subset of the system consisting of 8 BPMs and 4 corrector magnets in each ring was installed and successfully tested during the RHIC 2010 run; and the complete system is being installed for the 2011 run. A description of the overall system architecture and results with beam will be discussed.
 
 
MOP275 Beam Loss Control for the NSLS-II Storage Ring injection, dipole, beam-losses, shielding 624
 
  • S.L. Kramer, J. Choi
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by U.S. DOE, Contract No.DE-AC02-98CH10886
The shielding design for the NSLS-II storage ring is designed for the full injected beam losses in two periods of the ring around the injection point, but for the remainder of the ring its shielded for <10% top-off injection beam. This will require a system to insure that beam losses do not exceed these levels for time sufficient to cause excessive radiation exposure outside the shield walls. This beam Loss Control and Monitoring (LCM) system will control the beam losses to the more heavily shielded injection region while monitoring the losses outside this region. To achieve this scrapers are installed in the injection region to intercept beam particles that might be lost outside this region. The scrapers will be thin (< 1Xrad) that will allow low energy electrons to penetrate and the subsequent dipole will separate them from the stored beam. These thin scrapers will reduce the radiation from the scraper compared to thicker scrapers. The dipole will provide significant local shielding for particles that hit inside the gap and a source for the loss monitor system that will measure the amount of beam lost in the injection region.
* Beam Loss Monitors for NSLS-II Storage Ring, S.L. Kramer & P. Cameron, these proceedings
 
 
MOP277 The Machine Protection System for the R&D Energy Recovery LINAC status, linac, interlocks, collider 630
 
  • Z. Altinbas, J.P. Jamilkowski, D. Kayran, R.C. Lee, B. Oerter
    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 Machine Protection System (MPS) is a device-safety system that is designed to prevent damage to hardware by generating interlocks, based upon the state of input signals generated by selected sub-systems. It protects all the key machinery in the R&D Project called the Energy Recovery LINAC (ERL) against the high beam current. The MPS is capable of responding to a fault with an interlock signal within several microseconds. The ERL MPS is based on a National Instruments CompactRIO platform, and is programmed by utilizing National Instruments' development environment for a visual programming language. The system also transfers data (interlock status, time of fault, etc.) to the main server. Transferred data is integrated into the pre-existing software architecture which is accessible by the operators. This paper will provide an overview of the hardware used, its configuration and operation, as well as the software written both on the device and the server side.
 
 
MOP279 Synchronize Lasers to LCLS e- Beam laser, electron, cavity, LLRF 636
 
  • G. Huang
    TUB, Beijing, People's Republic of China
  • J.M. Byrd, L.R. Doolittle, R.B. Wilcox
    LBNL, Berkeley, California, USA
 
  Fiber based synchronization system is used in LCLS to synchronize the laser for pump probe experiment to average electron beam arrival time. Electron bunch arrival time measured by phase cavity is one of the best measurement for FEL X pulse until now. The average bunch arrival time is transmitted through electronic length stabilized fiber link to AMO and other experiment hall. The laser oscillator is phase locked to this reference signal to maintain low jitter and drift between pump and probe. The in loop error shows the jitter is less then 100 fs and meets the experiment requirement.  
 
MOP282 A Deterministic, Gigabit Serial Timing, Synchronization and Data Link for the RHIC LLRF LLRF, site, diagnostics, target 642
 
  • T. Hayes, F. Severino, K.S. Smith
    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.
A critical capability of the new RHIC low level rf system is the ability to synchronize signals across multiple locations. The Update Link provides this functionality. The Update Link is a deterministic serial data link based on the Xilinx Aurora protocol that is broadcast over fiber optic cable at 1 gigabit per second. The link provides timing events and data packets as well as time stamp information for synchronizing diagnostic data from multiple sources.
 
 
MOP283 A Hardware Overview of the RHIC LLRF Platform site, LLRF, monitoring, status 645
 
  • T. Hayes, K.S. Smith
    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 RHIC LLRF platform is a flexible, modular system designed around a carrier board with six XMC daughter sites. The carrier board features a Xilinx FPGA with an embedded, hard core Power PC that is remotely reconfigurable. It serves as a front end computer (FEC) that interfaces with the RHIC control system. The carrier provides high speed serial data paths to each daughter site and between daughter sites as well as four generic external fiber optic links. It also distributes low noise clocks and serial data links to all daughter sites and monitors temperature, voltage and current. To date, two XMC cards have been designed: a four channel high speed ADC and a four channel high speed DAC.
 
 
MOP284 A High Performance DAC / DDS Daughter Module for the RHIC LLRF Platform LLRF, luminosity, synchrotron, injection 648
 
  • T. Hayes, M. Harvey, G. Narayan, F. Severino, K.S. Smith, S. Yuan
    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 RHIC LLRF upgrade is a flexible, modular system. Output signals are generated by a custom designed XMC card with 4 high speed digital to analog converters interfaced to a high performance field programmable gate array (FPGA). This paper discusses the hardware details of the XMC DAC board as well as the implementation of a low noise rf synthesizer with digital IQ modulation. This synthesizer also provides injection phase cogging and frequency hop rebucketing capabilities.
 
 
MOP290 Self Excited Operation for a 1.3 GHz 5-cell Superconducting Cavity cavity, TRIUMF, feedback, superconducting-cavity 660
 
  • K. Fong, M.P. Laverty, Q. Zheng
    TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
  • E.P. Chojnacki, G.H. Hoffstaetter, D. Meidlinger, S.P. Wang
    CLASSE, Ithaca, New York, USA
 
  Self-Excited operation of a resonant system does not require any external frequency tracking as the frequency is determined by the phase lag of the self-excited loop, it is therefore particularly useful for testing high Q RF cavities that do not have an automatic tuning mechanism. Self-exited operation has long been shown to work with single-cell cavities. We have recently demonstrated that it is also possible for multi-cell cavities, where multiple resonant modes are present. The Cornell 1.3 GHz 5-cell superconducting cavities was operated using Self-Excited operation and we were able to lock to the accelerating (pi) mode, despite the presence of neighbouring modes that are less than 10 MHz away. By means of the loops phase advance, we were able to select which mode was excited.  
 
MOP292 Universal FMC-Compliant Module for xTCA Systems power-supply, monitoring, impedance, target 663
 
  • D.R. Makowski, G.W. Jabłoński, T. Kozak, A. Mielczarek, A. Napieralski
    TUL-DMCS, Łódź, Poland
 
  Funding: The research leading to these results has received funding from Polish National Science Council Grant 642/N-TESLAXFEL/09/2010/0.
The Advanced Telecommunications Computing Architecture (ATCA), MicroTCA (uTCA) and Advanced Mezzanine Card (AMC) standards, known as xTCA, provide unique features desired by various control systems of particle accelerators. The standards provide availability and operability as high as 99.999 %. A significant number of additional features must be implemented to take a full advantage of xTCA standards and gain the required availability. On the other hand, many control systems require various data acquisition and control modules with different number of input analogue and digital inputs or outputs as defined by their respective system specifications. The paper presents an universal base module, designed according to the AMC standard with an FPGA Mezzanine Card connector, that can be used for fast development of input-output subsystems. The module consists of two submodules. The digital part is designed according to the AMC standard while the main input-output functionality is realized by the FPGA Mezzanine Card part. The FMC submodule provides the functionality required by the specification of the LLRF system.
 
 
MOP293 Performance of Analog Signal Distribution in the ATCA Based LLRF System LLRF, radio-frequency, FEL, linac 666
 
  • K. Czuba, L. Butkowski, S. Jabłoński, P. Przybylski, D. Sikora
    Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
  • W. Jałmużna, D.R. Makowski
    TUL-DMCS, Łódź, Poland
  • T. Jezynski, F. Ludwig
    DESY, Hamburg, Germany
 
  The Low Level Radio Frequency System (LLRF) for the European X-FEL must provide exceptional stability of the accelerating RF field in the accelerating cavities. The regulation requirements of 0.01% and 0.01 degrees in amplitude and phase respectively must be achieved at a frequency of 1.3 GHz while keeping low drifts (during RF pulse). The quality of analog signal processing and distribution plays a crucial role in achieving these goals. The RF signals are connected to the Rear Transition Module (RTM), downconverted there into intermediate frequency (IF) signals and finally sampled at AMC-ADC module. The high quality of the signals (SNR, low crosstalk) must be assured across all the way. The paper presents the results of development of ATCA based LLRF system for XFEL. The special attention is paid to RTM module with downconverters and carrier board conducting analog signals to the AMC-ADC and the AMC Vector Modulator module in the presence of digital processing components (FPGA, DSP).  
 
MOP295 The Low-level Radio Frequency System for the Superconducting Cavities of National Synchrotron Light Source II LLRF, cavity, SRF, storage-ring 669
 
  • H. Ma, J. Cupolo, B. Holub, J. Oliva, J. Rose, R. Sikora, M. Yeddulla
    BNL, Upton, Long Island, New York, USA
 
  Funding: US DOE
A digital low-level radio frequency (LLRF) field controller has been developed for the storage ring of The National Synchrotron Light Source-II (NSLS-II). The primary performance goal for the LLRF is to support the required RF operation of the superconducting cavities with a beam current of 500mA and a 0.14 degree or better RF phase stability. The digital field controller is FPGA-based, in a standard format 19”/1-U chassis. It has an option of high-level control support with MATLAB running on a local host computer through a USB2.0 port. The field controller has been field tested with the high-power superconducting RF (SRF) at Canadian light Source, and successfully stored a high beam current of 250 mA. The test results show that required specifications for the cavity RF field stability are met. This digital field controller is also currently being used as a development platform for other functional modules in the NSLS-II RF systems.
 
 
MOP296 Embedded System Architecture and Capabilities of the RHIC LLRF Platform LLRF, feedback, monitoring, low-level-rf 672
 
  • F. Severino, M. Harvey, T. Hayes, L.T. Hoff, R.C. Lee, A. Marusic, P. Oddo, K.S. Smith, K.L. Unger
    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.
A high performance FPGA based platform has been developed for the RHIC Low Level RF system upgrade, and is now replacing our aging VME based systems. This new platform employs a sophisticated embedded architecture to implement its core functionality. This architecture provides a control system interface, manages remote access to all configuration parameters and diagnostic data, supports communication between all system components, enables real time application specific processing, monitors system health, etc. This paper will describe the embedded architecture and its capabilities, with emphasis on its application at RHIC.
 
 
MOP297 A Bunch to Bucket Phase Detector for the RHIC LLRF Upgrade Platform LLRF, feedback, injection, synchrotron 675
 
  • K.S. Smith, M. Harvey, T. Hayes, G. Narayan, S. Polizzo, F. Severino
    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
As part of the overall development effort for the RHIC LLRF Upgrade Platform, a 4 channel ADC daughter module was developed to provide high speed, wide dynamic range digitizing and processing of signals from DC to several hundred megahertz. The first operational use of this card was to implement the bunch to bucket phase detector for the RHIC LLRF beam control feedback loops. This paper will describe the design and performance features of this daughter module as a bunch to bucket phase detector, and also provide an overview of its place within the overall LLRF platform architecture as a high performance digitizer and signal processing module suitable to a variety of applications.
 
 
MOP298 Commisioning Results from the Recently Upgraded RHIC LLRF System LLRF, cavity, feedback, damping 678
 
  • K.S. Smith, M. Harvey, T. Hayes, G. Narayan, F. Severino, S. Yuan, A. Zaltsman
    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
During RHIC Run 10, the first phase of the LLRF Upgrade was successfully completed. This involved replacing the aging VME based system with a modern digital system based on the recently developed RHIC LLRF Upgrade Platform, and commissioning the system as part of the normal RHIC start up process. At the start of Run 11, the second phase of the upgrade is underway, involving a significant expansion of both hardware and functionality. This paper will review the commissioning effort and provide examples of improvements in system performance, flexibility and scalability afforded by the new platform.
 
 
MOP299 Commissioning and Performance of the BNL EBIS LLRF System cavity, LLRF, resonance, multipactoring 681
 
  • S. Yuan, M. Harvey, T. Hayes, G. Narayan, F. Severino, K.S. Smith, A. Zaltsman
    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 Beam Ion Source (EBIS) LLRF system utilizes the RHIC LLRF upgrade platform to achieve the required functionality and flexibility. The LLRF system provides drive to the EBIS high-level RF system, employs IQ feedback to provide required amplitude and phase stability, and implements a cavity resonance control scheme. The embedded system provides the interface to the existing Controls System, making remote system control and diagnostic possible. The flexibility of the system allows us to reuse VHDL codes, develop new functionalities, improve current designs, and implement new features with relative ease. In this paper, we will discuss the commissioning process, issues encountered, and performance of the system.
 
 
MOP300 The Spallation Neutron Source Eight-Channel Pulsed Power Meter EPICS, monitoring, klystron, LLRF 684
 
  • M.T. Crofford, X. Geng, T.W. Hardek
    ORNL, Oak Ridge, Tennessee, USA
  • T.L. Davidson
    ORNL RAD, Oak Ridge, Tennessee, USA
 
  The Spallation Neutron Source (SNS) Low Level Radio Frequency (LLRF) Control System currently utilizes the High-Power Protection Module (HPM) to monitor RF power levels, arc faults, and associated signals for the protection of the RF systems and accelerating cavities. The HPM is limited to seven RF channels for monitoring signals which in some instances leaves some signals of interest unmonitored. In addition, the HPM does not support monitoring of RF frequencies below 100 MHz which makes it unusable for our Ring and Ion Source systems that operate at 1 and 2 MHz respectively. To alleviate this problem, we have developed a microprocessor based eight channel pulsed RF power meter that allows us to monitor additional channels between the frequency range of 1 MHz to 2.5 GHz. This meter has been field tested in several locations with good results and plans are in place for a wider deployment.  
 
MOP304 Development of an X-Ray Beam Size Monitor with Single Pass Measurement Capability for CesrTA electron, optics, positron, photon 687
 
  • N.T. Rider, J.P. Alexander, M.G. Billing, J. Dobbins, R.E. Meller, M.A. Palmer, D.P. Peterson, C.R. Strohman
    CLASSE, Ithaca, New York, USA
  • J.W. Flanagan
    KEK, Ibaraki, Japan
 
  The CESR Test Accelerator (CesrTA) program targets the study of beam physics issues relevant to linear collider damping rings. This endeavor requires new instrumentation to study the beam dynamics along trains of ultra low emittance bunches. A key element of the program has been the development of an x-ray beam size monitor capable of collecting single pass measurements of individual bunches in a train over thousands of turns. This instrument utilizes custom, high bandwidth amplifiers and digitization hardware to collect signals from a linear InGaAs diode array. The digitizer is synchronized with the CESR timing system and is capable of recording beam size measurements for bunches spaced by as little as 4ns. The x-ray source is a bending magnet with Ec=0.6 keV during 2 GeV CesrTA operations. For these conditions the amplifier dynamic range was optimized to allow measurements with 3x109 to 1011 particles per bunch. Initial testing is complete. Data analysis and examples of key measurements which illustrate the instrument's performance are presented. This device offers unique measurement capabilities applicable to future high energy physics accelerators and light sources.  
 
TUOBN3 Witness Bunch Acceleration in a Multi-bunch PWFA plasma, wakefield, acceleration, electron 712
 
  • P. Muggli, B.A. Allen, Y. Fang
    USC, Los Angeles, California, USA
  • M. Babzien, M.G. Fedurin, K. Kusche, R. Malone, C. Swinson, V. Yakimenko
    BNL, Upton, Long Island, New York, USA
 
  Funding: Work supported by US DoE and NSF
We present initial experimental results showing the excitation of plasma wakefields by a train of two drive bunches. These wakefields are experienced by a trailing witness bunch that gains energy while retaining a finite energy spread. These well controlled plasma wakefield accelerator (PWFA) experiments are important to test the theory of the PWFA and serve as a testbed for techniques that will be used in high energy experiments.
 
slides icon Slides TUOBN3 [5.432 MB]  
 
TUODN2 Exploration of Parallel Optimization Techniques for Accelerator Design target, quadrupole, coupling, simulation 787
 
  • Y. Wang, M. Borland, V. Sajaev
    ANL, Argonne, USA
 
  Funding: Work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357.
Optimization through simulation is a time-consuming task in accelerator design, especially for high dimensional problems. We explored several parallel optimization techniques, including Parallel Genetic Algorithm (PGA), Hybrid Parallel Simplex (HPS), and Parallel Particle Swarm Optimization (PPSO), to solve some real world problems. The serial simplex method in elegant was used as a benchmark for newly-developed parallel optimization algorithms in Pelegant. PGA and HPS are not faster than the serial simplex method, but they more reliably find the global optimum. PPSO is well suited for parallel computing, allowing significantly faster turn-around given sufficient computing resources. Parallel optimization implementations in Pelegant thus promise to not only make optimization results more reliable, but also open the possibility of fast, "real time" optimization of complex problems for accelerator operation.
 
slides icon Slides TUODN2 [0.218 MB]  
 
TUP015 Conceptual Design of the Project-X 1.3 GHz, 3-8 GeV Pulsed Linac linac, cavity, klystron, feedback 841
 
  • N. Solyak, Y.I. Eidelman, S. Nagaitsev, J.-F. Ostiguy, A. Vostrikov, V.P. Yakovlev
    Fermilab, Batavia, USA
 
  The Project-X, a multi-MW proton source, is under development at Fermilab. It enables a Long Baseline Neutrino Experiment via a new beam line pointed to DUSEL in Lead, South Dakota, and a broad suite of rare decay experiments. The facility contains 3-GeV 1-mA CW superconducting linac. In the second stage of about 5% of the H beam is accelerated up to 8 GeV in a 1.3 GHz SRF pulse linac to Recycler/Main Injector. In order to mitigate the problem with the stripping foil heating during injection to the Main Injector, the pulses with higher current are accelerated in CW linac together with 1 mA beam for further acceleration in the pulse linac. The optimal current in the pulse linac is discussed as well as limitations that determine it's selection. A concept design of the pulse linac is described. The lattice design is presented as well as RF stability analysis. The necessity of the HOM couplers is discussed also.  
 
TUP032 Development of 1.3 GHz Prototype Niobium Single Cell Superconducting Cavity Under IIFC Collaboration cavity, vacuum, niobium, electron 871
 
  • A. Puntambekar, M. Bagre, J. Dwivedi, P.D. Gupta, R.K. Gupta, S.C. Joshi, G.V. Kane, R.S. Sandha, S.D. Sharma, P. Shrivastava
    RRCAT, Indore (M.P.), India
  • C.A. Cooper, M.H. Foley, T.N. Khabiboulline, C.S. Mishra, J.P. Ozelis, A.M. Rowe, G. Wu
    Fermilab, Batavia, USA
  • V. Jain
    IIT, Mumbai, India
  • D. Kanjilal, K.K. Mistri, P.N. Potukuchi, J. Sacharias
    IUAC, New Delhi, India
  • V.C. Sahni
    Homi Bhbha National Institute (HBNI), DAE, Mumbai, India
 
  Under Indian Institutions Fermilab collaboration (IIFC), Raja Ramanna Centre for Advanced Technology (RRCAT) Indore, Inter University Accelerator Centre (IUAC) New Delhi and Fermi National Accelerator Laboratory (FNAL) have developed two prototype 1.3 GHz niobium single cell superconducting cavities. Development of forming tools, forming of half cells, machining of components, development of welding fixtures along with RF & vacuum qualification were carried out at RRCAT. The electron beam welding was carried out at IUAC. The fabricated prototype cavities were tested for RF and vacuum leak tightness up to 77 K at RRCAT before shipment to FNAL. Processing, consisting of CBP, EP, and heat treatment was carried out jointly by FNAL and Argonne National Laboratory in USA. Both the prototype cavities were tested at 2 K in the VTS facility at FNAL and have achieved the accelerating gradient of ~ 19 to 21 MV/m with Q > 1.5 ·10+10. This paper will report the developmental efforts carried out in tooling, forming, machining, welding & various qualification procedures adopted. The paper will also present the processing and the 2 K test results.  
 
TUP039 Low Latency Data Transmission in LLRF Systems LLRF, alignment, feedback, free-electron-laser 877
 
  • D.R. Makowski, G.W. Jabłoński, A. Napieralski, P. Predki
    TUL-DMCS, Łódź, Poland
 
  Funding: The research leading to these results has received funding from the Polish National Science Council Grant 642/N-TESLAXFEL/09/2010/0.
The linear accelerators applied to drive Free Electron Lasers (FELs), such as the X-Ray Free Electron Laser (XFEL), require sophisticated control systems. The Low Level Radio Frequency (LLRF) control systems of a linear accelerator should provide signal to vector modulator in less than 1 microsecond. Therefore the latency of communication interfaces is more important than their throughput. The paper discusses the application of serial gigabit links for transmission of data in LLRF systems. The latency of pure serial transmission based on Xilinx RocketIO transceivers was evaluated and compared with Xilinx Aurora protocol. The developed low latency protocol will be also presented.
 
 
TUP040 Asset Management Application for a LLRF Control System LLRF, laser, electron, synchrotron 880
 
  • B. Sakowicz, M. Kamiński, D.R. Makowski, P. Mazur, A. Napieralski, A. Piotrowski
    TUL-DMCS, Łódź, Poland
 
  Funding: The research leading to these results has received funding from the Polish National Science Council Grant 642/N-TESLAXFEL/09/2010/0.
In this article an asset management application for a low level radio frequency (LLRF) control system is described. The system was developed to facilitate management of some aspects of controlling a linear accelerator and, among others, provides means to manage and program multiple firmware versions for a large, distributed and frequently changing set of FPGA devices that are present in a control system. The system introduces a multihierarchical tree-based representation of almost all assets involved in accelerator management.*
* Kamiński M., Makowski D., Mazur P., Murlewski J., Sakowicz B.: "Firmware application for LLRF control system based on the Enterprise Service Bus", CADSM 2009, Ukraine, ISBN 978-966-2191-05-9
 
 
TUP042 RF Measurements and Numerical Simulations for the Model of the Bilbao Linac Double Spoke Cavity cavity, simulation, HOM, ion 886
 
  • J.L. Munoz, I. Bustinduy, N. Garmendia, V. Toyos
    ESS Bilbao, Bilbao, Spain
  • E. Asua
    UPV-EHU, Leioa, Spain
  • F.J. Bermejo
    Bilbao, Faculty of Science and Technology, Bilbao, Spain
  • V. Etxebarria, J. Portilla
    University of the Basque Country, Faculty of Science and Technology, Bilbao, Spain
  • J. Feuchtwanger
    ESS-Bilbao, Zamudio, Spain
  • J. Lucas
    Elytt Energy, Madrid, Spain
 
  A model of a double spoke resonant cavity (operating frequency 352.2 MHz, βg=0.39) has been designed and fabricated in aluminium. The RF characteristics of the cavity have been measured in our laboratory. Experimental measurements have involved the determination of the main cavity parameters, and the characterization of the accelerating electric field profile along the cavity axis by means of a fully automated bead-pullmethod. Additionally, numerical simulations using COMSOL code have been used to fully characterize the cavity. Electromagnetic numerical simulations of the cavity have been also performed to determine its main figures of merit and to identify the most suitable position for opening a port to install a power coupler. In this paper we report the cavity cold model description, the experimental setup and corresponding techniques, together with the numerical methods. The obtained results are described and discussed in detail.  
 
TUP061 FPC Conditioning Cart at BNL vacuum, gun, klystron, cavity 928
 
  • W. Xu, Z. Altinbas, S.A. Belomestnykh, I. Ben-Zvi, A. Burrill, S. Deonarine, D.M. Gassner, J.P. Jamilkowski, P. Kankiya, D. Kayran, N. Laloudakis, L. Masi, G.T. McIntyre, D. Pate, D. Phillips, T. Seda, A.N. Steszyn, T.N. Tallerico, R.J. Todd, D. Weiss, A. Zaltsman
    BNL, Upton, Long Island, New York, USA
  • M.D. Cole, G.J. Whitbeck
    AES, Medford, NY, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
The 703MHz superconducting gun will have 2 fundamental power couplers (FPCs). Each FPC will deliver up to 500kW of RF power. In order to prepare the couplers for high power RF service and process multipacting, the FPCs should be conditioned before they are installed in the gun. A conditioning cart based test stand, which includes a vacuum pumping system, controllable bake-out system, diagnostics, interlocks and data log system has been designed, constructed and commissioned by collaboration of BNL and AES. This paper presents FPC conditioning cart systems and summarizes the conditioning process and results.
 
 
TUP066 Three-cell Traveling-wave Superconducting Test Structure cavity, feedback, accelerating-gradient, linac 940
 
  • P.V. Avrakhov, A. Kanareykin
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • S. Kazakov, N. Solyak, G. Wu, V.P. Yakovlev
    Fermilab, Batavia, USA
 
  Use of a superconducting traveling wave accelerating (STWA) structure* with a small phase advance per cell rather than a standing wave structure may provide a significant increase of the accelerating gradient in the ILC linac. For the same surface electric and magnetic fields the STWA achieves an accelerating gradient 1.2 larger than TESLA-like standing wave cavities. The STWA allows also longer acceleration cavities, reducing the number of gaps between them. However, the STWA structure requires a SC feedback waveguide to return the few hundreds of MW of circulating RF power from the structure output to the structure input. A test single-cell cavity with feedback was designed, manufactured and successfully tested** demonstrating the possibility of a proper processing to achieve a high accelerating gradient. These results open the way to take the next step of the TW SC cavity development: to build and test a traveling-wave three-cell cavity with a feedback waveguide. The latest results of the single-cell cavity tests are discussed as well as the design of the test 3-cell TW cavity.
* P. Avrakhov, et al, Phys. of Part. and Nucl. Let, 2008, Vol. 5, No. 7, p. 597
** G. Wu, et al, IPAC 2010, THPD048
 
 
TUP073 Development of an L-band Ferroelectric Phase Shifter simulation, insertion, linac, high-voltage 955
 
  • S. Kazakov, N. Solyak, V.P. Yakovlev
    Fermilab, Batavia, USA
  • J.L. Hirshfield
    Yale University, Physics Department, New Haven, CT, USA
  • A. Kanareykin, E. Nenasheva
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • S.V. Shchelkunov
    Yale University, Beam Physics Laboratory, New Haven, Connecticut, USA
 
  Effective operation of the RF cavities in the superconducting accelerators demands fast, high-power RF vector modulators. Recent progress in development of the new materials, ferroelectrics, having tunable dielectric constant and acceptable losses [*] gives the possibility development of such devises. In previous papers [**-***] the authors described different L-band ferroelectric phase shifter designs . At low RF level high operation speed of 2 degree/nsec was demonstrated in waveguide phase shifter. However, the experiments show that a special technology is to be developed that provides a good electric contact between ceramics and the metallic wall. In present paper a new design of the fast high–power ferroelectric phase shifter is described based on the simple ferroelectric elements.
* A. Kanareykin, et al, IPAC 2010, p. 3987
** S. Kazakov, et al, “Fast Ferroelectric Phase Shifter Design For ERLs,” 45th ICFA Beam Dynamics Workshop, 2009
*** S. Kazakov, et al, PAC2007, p. 599.
 
 
TUP080 Tests of a Tuner for a 325 MHz SRF Spoke Resonator cavity, resonance, SRF, monitoring 973
 
  • Y.M. Pischalnikov, E. Borissov, T.N. Khabiboulline, R.L. Madrak, R.V. Pilipenko, L. Ristori, W. Schappert
    Fermilab, Batavia, USA
 
  Funding: Work is supported by the U.S. Department of Energy
Fermilab is developing 325 MHz SRF spoke cavities for the proposed ProjectX. A compact fast/slow tuner has been developed to compensate microphonics and Lorentz force detuning. The modified tuner design and results of 4K tests of the first prototype are presented.
 
 
TUP082 Test of a Coaxial Blade Tuner at HTS/FNAL cavity, SRF, resonance, cryomodule 976
 
  • Y.M. Pischalnikov, S. Barbanotti, E.R. Harms, A. Hocker, T.N. Khabiboulline, W. Schappert
    Fermilab, Batavia, USA
  • A. Bosotti, C. Pagani, R. Paparella
    INFN/LASA, Segrate (MI), Italy
 
  Funding: Work is supported by the U.S. Department of Energy
Fermilab is building Cryomodule 2 for ILCTA facility at NML. A coaxial blade tuner has been chosen for the CM2 1.3GHz SRF cavities. A summary of results from cold test of the tuners in the Fermilab Horizontal Test Stand will be presented.
 
 
TUP083 Phase and Frequency Locked Magnetrons for SRF Sources resonance, SRF, solenoid, insertion 979
 
  • M. Popovic, A. Moretti
    Fermilab, Batavia, USA
  • M.A.C. Cummings, A. Dudas, R.P. Johnson, M.L. Neubauer, R. Sah
    Muons, Inc, Batavia, USA
 
  Funding: Supported in part by STTR Grant DE-SC0002766
In order to make use of ferrite and/or garnet materials in the phase and frequency locked magnetron, for which Muons, Inc., received a Phase II award, materials must be tested in two orthogonal magnetic fields. One field is from the biasing field of the magnetron, the other from the biasing field used to control the ferrite within the anode structure of the magnetron. A test fixture was built and materials are being tested to determine their suitability. The status of those material tests are reported on in this paper.
 
 
TUP086 Microphonics control for Project X cavity, linac, cryomodule, SRF 988
 
  • W. Schappert, S. Barbanotti, J. Branlard, G.I. Cancelo, R.H. Carcagno, M.S. Champion, B. Chase, I.G. Gonin, A.L. Klebaner, D.F. Orris, T.J. Peterson, Y.M. Pischalnikov, L. Ristori, N. Solyak, V.P. Yakovlev
    Fermilab, Batavia, USA
 
  Funding: Work is supported by the U.S. Department of Energy
The proposed multi-MW Project X facility at Fermilab will employ cavities with bandwidths as narrow as 20 Hz. This combination of high RF power with narrow bandwidths combined requires careful attention to detuning control if these cavities are to be operated successfully. Detuning control for Projects X will require a coordinated effort between the groups responsible for various machine subsystems. Considerable progress in this area has been made over the past year.
 
 
TUP114 Rugged Solid-state RF Amplifiers for Accelerator Applications - Design and Performance from an Industry Perspective rf-amplifier, monitoring, status, target 1053
 
  • S.C. Dillon, B.S. Nobel, J.L. Reid, C.P. Schach, W.J. Villena Gonzales
    Tomco Technologies, Stepney, South Australia, Australia
 
  Recent advances in transistor technology are making solid-state RF amplifiers an increasingly viable alternative to tube systems in accelerator applications. This paper details the development and performance of a range of new high power amplifiers, based on current MOSFET technology, and designed specifically for this application. A generic modular architecture that can be used to construct high power CW amplifier systems operating from HF up to S-band, is detailed. Key design considerations in terms of modularity, redundancy, reliability and cost are discussed.  
 
TUP117 Solid State Direct Drive RF LINAC: High Power Experimental Program cavity, impedance, linac, high-voltage 1056
 
  • T.J.S. Hughes, M. Back, R. Fleck, M. Hergt, R. Irsigler, T. Kluge, J. Sirtl
    Siemens AG, Erlangen, Germany
  • O. Heid
    Siemens AG, Healthcare Technology and Concepts, Erlangen, Germany
 
  We report on a 150MHz λ/4 coaxial resonator driven by 32 integrated class F RF power modules according to our direct drive concept [1,2]. Electric fields of 60MV/m at the resonator gap have been reached, which correspond to 80kW RF power. This power level has been achieved at 160V DC supply voltage, significantly less than the component limits. The observed power and Q values can be explained by a simple equivalent circuit. The model predicts that 64 modules at 160V DC supply voltage may provide 170kW RF power, and that 250V DC supply voltage should yield 400kW. The corresponding 134MV/m gap E field may not be reachable due to vacuum flashover.
* Heid O., Hughes T. THPD002, IPAC10, Kyoto, Japan
** Hergt M et al, 2010 IEEE International Power Modulator and High Voltage Conf., Atlanta GA, USA
*** Heid O., Hughes T. THP068, LINAC10, Tsukuba, Japan
 
 
TUP123 Performance of the 352-MHz 4-kW CW Solid State RF Power Amplifier System using 1-kW Push-pull Devices klystron, cavity, storage-ring, simulation 1059
 
  • D. Horan, G.J. Waldschmidt
    ANL, Argonne, USA
 
  Funding: Work supported by U. S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract No. DE-AC02-06CH11357
Development and testing of a prototype 352-MHz, 4-kW cw solid state rf power amplifier system is underway at the Advanced Photon Source to study and evaluate the performance advantages of an upgrade to solid state rf power technology at the APS. General performance measurement data on the assembled amplifier system is discussed, with emphasis on efficiency improvements possible through the use of dynamic drain voltage control.
 
 
TUP130 Experiments on Voltage Droop Compensation for High Power Marx Modulators high-voltage, factory, linac, simulation 1076
 
  • P. Chen, M. Lundquist, D. Yu
    DULY Research Inc., Rancho Palos Verdes, California, USA
 
  Funding: Work supported by DOE SBIR Phase II grant DE-FG02-08ER85052
Marx modulators, promising higher efficiency, longer lifetime and reduced cost compared with existing hard tube modulator options, are under intensive research. In this article, we describe the progress of work on our voltage droop compensation scheme for a Marx modulator. Experimental results on a compensation circuit at moderate voltage are presented.
 
 
TUP133 Mechanical Design and Fabrication of a New RF Power Amplifier for LANSCE cathode, cavity, rf-amplifier, target 1085
 
  • Z. Chen, M.J. Borden, N.K. Bultman, C.A. Chapman, J. Davis, J.L. Ferris, T.S. Gomez, J.T.M. Lyles, A.C. Naranjo
    LANL, Los Alamos, New Mexico, USA
  • D. Baca, R.E. Bratton, R.D. Summers
    Compa Industries, Inc., Los Alamos, New Mexico, USA
 
  Funding: Work supported by the United States Department of Energy, National Nuclear Security Agency, under contract DE-AC52-06NA25396
A Full-scale prototype of a new 201 MHz RF Final Power Amplifier (FPA) for Los Alamos Neutron Science Center (LANSCE) has been designed, fabricated, assembled and installed in the test facility. This prototype was successfully tested and met the physics and electronics design criteria. With a goal to produce 3.2 MW peak power at 15% duty factor, at the elevation of over 2 km in Los Alamos, The team faced design and manufacturing challenges. The mechanical design of the final power amplifier was built around a Thales TH628 Diacrode®, a state-of-art tetrode power tube*. The main structure includes Input circuit, Output circuit, Grid decoupling circuit, Output coupler, Tuning pistons, and a cooling system. Many kinds of material were utilized to make this new RF amplifier. The FPA is nearly 1000 kg and installed in a beam structural support stand. In this paper, we summarize the FPA design basis and fabrication, plating, and assembly process steps with necessary lifting and handling fixtures. In addition, to ensure the quality of the FPA support structure a finite element analysis with seismic design forces has also been carried out.
* J. Lyles, S. Archuletta, N. Bultman, Z. Chen, et al., “Design of a New VHF RF Power Amplifier System for LANSCE”, IPAC’10, Kyoto, Japan, May 24-28, 2010.
 
 
TUP134 New High Power Test Facility for VHF Power Amplifiers at LANSCE power-supply, DTL, status, monitoring 1088
 
  • J.T.M. Lyles, S. Archuletta, J. Davis, L. Lopez, D. Rees, M.R. Rodriguez, G. M. Sandoval, Jr., A. Steck, D.J. Vigil
    LANL, Los Alamos, New Mexico, USA
  • D. Baca, R.E. Bratton, R.D. Summers
    Compa Industries, Inc., Los Alamos, New Mexico, USA
  • N.W. Brennan
    Texas A&M University, College Station, Texas, USA
 
  Funding: Work supported by the United States Department of Energy, National Nuclear Security Agency, under contract DE-AC52-06NA25396
A new test facility was designed and constructed at Los Alamos Neutron Science Center (LANSCE) for testing the Thales TH628 Diacrode® and TH781 tetrode power amplifiers. Anode power requirements for the TH628 are 28 kV DC, with peak currents of 190 Amperes in long pulses. A new 225 uF capacitor bank supplies this demand. A charging power supply was obtained by re-configuring a 2 MW beam power supply remaining from another project. A traditional ignitron crowbar was designed to rapidly discharge the 88 kJ stored energy. The anode power supply was extensively tested using a pulsed tetrode switch and resistor load. A new Fast Protect and Monitor System (FPMS) was designed to take samples of RF reflected power, anode HV, and various tube currents, with outputs to quench the HV charging supply, remove RF drive and disable the conduction bias pulse to the grid of each tube during fault events. The entire test stand is controlled with a programmable logic controller, for normal startup sequencing and timing, protection against loss of cooling, and operator GUI.
 
 
TUP166 Novel Quench Detection System For HTS Coils target, extraction, power-supply, background 1136
 
  • P.N. Joshi, S. Dimaiuta, G. Ganetis, R.C. Gupta, Y. Shiroyanagi
    BNL, Upton, Long Island, New York, USA
 
  As a part of HTS magnet R&D, small coils are being built and tested to study quench properties in a systematic manner. Fot this purpose, multi-channel quench detection, fast and slow data logger, current ramp controller and energy extraction system was developed. This system had to be flexible, compact, economical and easy to use. The system is based on LabView and FPGA hardware from National Instrument.  
 
TUP175 Fabrication of the Jefferson Laboratory Cryogenic Control Reservoirs vacuum, cryogenics, superconducting-magnet, FEL 1157
 
  • M.L. Seely, E.C. Bonnema, D.J. Carvelli, E.K. Cunningham, E.C. Kasper, G.D. Korecky
    Meyer Tool & MFG, Oak Lawn, Illinois, USA
 
  Meyer Tool and Manufacturing of Oak Lawn IL is manufacturing six Cryogenic Control reservoirs CCRs) for the Jefferson Laboratory. Five of the CCRs will be installed in the new Super High Momentum Spectrometer (SHMS) planned for Jefferson Lab's Hall C and the sixth will be installed in Hall D. Both projects are part of the 12 GeV upgrade to the CEBAF accelerator . The CCRs are a cryogenic distribution box designed by the Jefferson Laboratory. They include internal reservoirs in order to provide a continuous supply liquid helium and liquid nitrogen to magnets through periods of disruption in the external supply. This paper discusses the manufacturing and process measures that were implemented in order to meet the Department of Energy requirements for pressure vessels (10CFR851 Appendix A Part 4), to eliminate brazing flux contamination, and to reduce weld distortion in multiple internal vessels. The CCRs will undergo pressure and vacuum testing at Meyer Tool before being installed by the magnet manufacturer.  
 
TUP178 Current Progress of TAMU3: A Block Coil Stress-managed High Field (>12T) Nb3Sn Dipole dipole, status, collider, target 1163
 
  • E.F. Holik, C.P. Benson, R. Blackburn, N. Diaczenko, T. Elliott, A. Jaisle, A.D. McInturff, P.M. McIntyre, A. Sattarov
    Texas A&M University, College Station, Texas, USA
 
  Funding: This work was supported by the U.S. Department of Energy under Grant DE-FG02-06ER41405
TAMU3 is a block-coil short model dipole which embodies for the first time at high field (>12T) strength the techniques of stress management within the superconducting windings. The dipole consists of two planar racetrack coil assemblies, assembled within the rectangular aperture of a flux return core. Each assembly contains an inner and outer winding, and a high-strength support structure which is integrated within the assembly to intercept the Lorentz stress produced from the inner winding so that it does not accumulate to produce high stress in the outer winding. Iso-static preload is applied by pressurizing a set of thin stainless steel bladders with molten Woods metal and then freezing the metal under pressure. Current technology, difficulties, and present status of construction of magnet assembly will be presented.
 
 
TUP182 In-situ System Identification for an Optimal Control of Magnet Power Supplies power-supply, factory 1172
 
  • X.H. Ke, F. Jenni
    FHNW, Windisch, Switzerland
 
  Funding: Paul Scherrer Institute, Switzerland
In particle accelerators, the magnet power supply system (controller, power stage and magnet) normally has a higher system order (>5). An exact model, representing the behavior of such a system, would be very helpful for an optimal control. For the control, the engineers are mainly not interested in the analytic model, which shows the exact internal mechanisms of the physical system, but, in a model describing the I/O behavior. Moreover, since the real elements do not exactly correspond to the design values, it is desirable to model the power supply system by means of system identification from measured properties. For that, a subspace based identification method is applied, which yields the observer for the self-optimizing high dynamic control of magnet power supplies at the Paul Scherrer Institute (PSI). The only inputs the identification needs are the measured DC-link voltage, the magnet voltage and the magnet current. With that it calculates a corresponding state space model for the system. The whole process is done automatically and in situ, which is a practical and meaningful approach to obtain the exact system information for control design.
 
 
TUP183 Self-optimizing High Dynamic Power Supply Control power-supply, feedback, damping 1175
 
  • X.H. Ke, F. Jenni
    FHNW, Windisch, Switzerland
  • H. Jäckle
    PSI, Villigen, Switzerland
 
  Funding: Paul Scherrer Institute, Switzerland
In 1999, the first fully digitally controlled magnet power supplies were put into operation at PSI (Paul Scherrer Institute, Switzerland). Today, approximately 1000 are in use at PSI and a multiple of that worldwide. This project aims at developing a high performance control scheme for a better dynamic behavior of today's magnet powers supplies, without reducing their excellent static behaviors. The resulting control strategy, an in situ identification based observer, combined with state space and proportional integral (SS-PI) control, leads to a significantly improved dynamic behavior of the existing power supplies. The whole commissioning, including system identification, as well as control parameter determination and optimization, is done automatically on the DSP with support of a PC. The control strategy has been implemented on the existing PSI controller and a 10A-corrector power supply, together with various magnets, by updating the software and/or firmware only. Currently, the new control strategy is being implemented and tested at PSI on a second generation Digital Power Electronic Control System (DPC) controller card.
 
 
TUP188 A New Power Supply System for the IEX Project at the APS power-supply, undulator, polarization, photon 1178
 
  • B. Deriy, M.S. Jaski, J. Wang
    ANL, Argonne, USA
 
  A new beamline providing circularly polarized x-rays that will cover photon energies from 250 eV to 2.5 keV is under development at the APS. Because of the unique requirements of the circular polarizing undulator constructed for this beamline, a new power supply system design is required. The undulator will contain twelve sets of electromagnetic coils – two main, two quasi-periodic, and eight correctors. The undulator will incorporate variable polarization control and reduction of the magnetic fields at so-called quasi-periodic pole locations for the purpose of suppressing the higher-order radiation harmonics. The challenges met in the power supply system design for the project will be discussed.  
 
TUP190 Upgrade of the APS Booster Synchrotron Magnet Ramp booster, dipole, injection, synchrotron 1181
 
  • C. Yao, B. Deriy, G. Feng, H. Shang, J. Wang
    ANL, Argonne, USA
 
  Funding: Work supported by U.S. Department of Energy, Offices of Science, Office of Basic Energy Sciences, under contract No. DE-AC02-06-CH11357
The APS booster is a 7-GeV electron synchrotron with 0.5-second cycle time. Both voltage and current ramp modes were in the original design but only the voltage ramp has been commissioned. Two software-based ramp control programs are used to regulate the current waveform to a linear ramp. The system has been operated for user beam operations for many years. Some instability exists in the ramp correction that requires manual intervention from time to time by the operators. Sensitivity of magnet currents to external changes, such as AC line voltage, harmonic interference from the high-power rf system, etc., has been observed. In order to meet the increased single-bunch-charge requirement of the APS upgrade we need more flexible current ramps such as flat porches for injection and extraction and smooth transitions. Recent efforts to develop an energy-saving operation mode also call for ramp improvement. This paper presents test results of a workstation-based current regulation program and an FPGA-based implementation as a future upgrade.
 
 
TUP191 Booster Main Magnet Power Supply, Present Operation and Potential Future Upgrades power-supply, booster, simulation, feedback 1184
 
  • E.M. Bajon, M. Bannon, G. Danowski, I. Marneris, J. Sandberg, S. Savatteri
    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 Brookhaven Booster Main Magnet Power Supply (MMPS) is a 24 pulse thyristor control supply, rated at 5500 Amps, ±2000 Volts, or 3000 Amps, ±6000 Volts. The power supply is fed directly from the power utility and the peak magnet power is 18 MWatts. This peak power is seen directly at the incoming ac line. This power supply has been in operation for the last 18 years. This paper will describe the present topology and operation of the power supply, the feedback control system and the different modes of operation of the power supply. Since the power supply has been in operation for the last 18 years, upgrading this power supply is essential. A new power supply topology has been studied where energy is stored in capacitor banks. DC to DC converters are used to convert the dc voltage stored in the capacitor banks to pulsed DC voltage into the magnet load. This enables the average incoming power from the ac line to be constant while the peak magnet power is pulsed to ± 18 MWatts. Simulations and waveforms of this power supply will be presented.
 
 
TUP193 NSLS-II Power Supply Controller power-supply, booster, diagnostics, storage-ring 1187
 
  • W. Louie, L.R. Dalesio, G. Ganetis, Y. Tian
    BNL, Upton, Long Island, New York, USA
 
  This paper presents the design of the National Synchrotron Light Source II (NSLS-II) Power Supply Controller (PSC). It consists of a main board, rear module and backplane. The main features of NSLS-II PSC included 256MB DDR2 memory for power supply system diagnostics, high speed serial link between PSC modules, an embedded microprocessor and a 100 Mbps Ethernet port. Each PSC module can be remotely programmed through network. NSLS-II PSC will be used to control power supplies in Storage Ring, Booster Ring and Transport line. The PSC also provides interface for the NSLS-II fast and slow orbits feedback system.  
 
TUP195 Commissioning the ALS Digital Power Supply Controller in the Booster Dipole and Quadrupole Magnet Power Supplies booster, injection, power-supply, quadrupole 1190
 
  • J.M. Weber, T. Scarvie, C. Steier, CA. Timossi
    LBNL, Berkeley, California, USA
 
  Funding: Supported by the U.S. Department of Energy under Contract No. DE-AC02-05CH11231.
The Advanced Light Source (ALS) is a third generation synchrotron light source that has been operating since 1993 at Berkeley Lab. A few years ago, the ALS was upgraded to achieve Top-Off Mode, which required replacing the booster dipole and quadrupole magnet power supplies to increase the peak booster beam energy from 1.5GeV to 1.9GeV. The original analog controller for each power supply has been replaced by a digital power supply controller (DPSC) to improve stability and resolution and provide a remote interface. The DPSC capabilities include 24-bit 100k-point digital reference waveform download and voltage reference generation, and complete digital current loop implementation. The hardware includes an FPGA with an embedded processor running a full EPICS IOC on VxWorks. This paper will present the current functionality of the DPSC as well as performance results from recent commissioning.

 
 
TUP196 SLAC P2 MARX Control System and Regulation Scheme power-supply, interlocks, status, simulation 1193
 
  • D.J. MacNair, M.A. Kemp, K.J.P. Macken, M.N. Nguyen, J.J. Olsen
    SLAC, Menlo Park, California, USA
 
  Funding: Work supported by the U.S. Department of Energy under contract number DE-AC02-76SF00515
The SLAC P2 MARX P2 Modulator consists of 32 cells charged in parallel by a -4000V supply and discharged in series to provide a -120 KV 140 amp 1.6 millisecond pulse. Each cell has a 350uF main storage capacitor. The voltage on the capacitor will droop approximately 640 volts during each pulse. Each cell will have a boost supply that can add up to 700V to the cell output. This allows the output voltage of the cell to remain constant within 0.1% during the pulse. The modulator output voltage control is determined by the -4KV charging voltage. A voltage divider will measure the modulator voltage on each pulse. The charging voltage will be adjusted by the data from previous pulses to provide the desired output. The boost supply in each cell consists of a 700V buck regulator in series with the main capacitor. The supply uses a lookup table for PWM control. The lookup table is calculated from previous pulse data to provide a constant cell output. The paper will describe the modulator and cell regulation used by the MARX modulator. Measured data from a single cell and three cell string will be included.
 
 
TUP208 DESIGNING A BEAM TRANSPORT SYSTEM FOR RHIC’S ELECTRON LENS electron, solenoid, dipole, beam-transport 1205
 
  • X. Gu, W. Fischer, R.C. Gupta, J. Hock, Y. Luo, M. Okamura, A.I. Pikin, D. Raparia
    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.
We designed two electron lenses to apply head-on beam-beam compensation for RHIC; they will be installed near IP10. The electron-beam transport system is an important subsystem of the entire electron-lens system. Electrons are transported from the electron gun to the main solenoid and further to the collector. The system must allow for changes of the electron beam size inside the superconducting magnet, and for changes of the electron position by 5 mm in the horizontal- and vertical-planes.
 
 
TUP217 The Application of 400KW DC Bank for Cryogenic System at NSRRC cryogenics, booster, synchrotron, superconducting-magnet 1217
 
  • H.C. Li, S.-H. Chang, W.-S. Chiou, F. Z. Hsiao, T.F. Lin, H.H. Tsai
    NSRRC, Hsinchu, Taiwan
 
  There will be a power sag (>50% drop) several times and annual maintenance of power company every year that course cryogenic system shutdown and take hours to recover. We install the AC UPS to maintain a steady power supply to the control circuit and low power devices to avoid such incidences. However, the AC UPS is not suitable for the 315-kW compressor with inverter due to the harmonic distortion effect and low power factor. We built two sets of 400-kW DC UPS (also called DC Bank system) to keep two 315-kW compressor in full load operation at least 3 minutes when power sag or power cut-off in 2010. The DC Bank was parallel connect to the inverter, thus, will not affect the inverter operation when DC Bank need to maintenance or failure. This paper presents the configuration of DC Bank and the test of the system. Results show that when the inverter is operated at 242KW with main power cut off, the helium compressor is keeping stable operation for 257 seconds by DC Bank support.  
 
TUP218 Design of a Liquid Helium Transfer System for the TPS Project cryogenics, SRF, storage-ring, electron 1220
 
  • H.H. Tsai, M.H. Chang, S.-H. Chang, W.-S. Chiou, F. Z. Hsiao, H.C. Li, M.-C. Lin, T.F. Lin, C.P. Liu, Ch. Wang
    NSRRC, Hsinchu, Taiwan
 
  The construction of the Taiwan Photon Source (TPS) storage ring is under way, to be completed in mid 2012. The new helium cryogenic system is provided from the Linde Company, to be installed after the TPS storage ring is completed. The super conducting radio frequency (SRF) cavities is needed to maintain the electron energy of storage ring and were operated at refrigeration mode such that the cold helium gas from the cavity cryostat is returned to the refrigerator. One distribution valve box and individual segments of multichannel transfer lines is required to supply the liquid helium and liquid nitrogen to the SRF cavities and recover the gas helium and gas nitrogen back to the cryogenic system. This paper is aimed to present the configuration and design features of the LHe transfer system. The heat load and pressure drop calculation of the transfer system was also presented.  
 
TUP222 Helium Release Rates and ODH Calculations from RHIC Magnet Line Cooling Line Failure vacuum, simulation, injection, collider 1232
 
  • C.J. Liaw, R. Than, J.E. Tuozzolo
    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.
A catastrophic failure of the magnet cooling lines, similar to the LHC superconducting bus failure incident, could discharge cold helium into the RHIC tunnel and cause an Oxygen Deficiency Hazard (ODH) problem. A SINDA/FLUINT® model, which simulated the 4.5K/ 4 atm helium flowing through the magnet cooling system distribution lines, then through a line break into the insulating vacuum volumes and discharging via the reliefs into the RHIC tunnel, had been developed. Arc flash energy deposition and heat load from the ambient temperature cryostat surfaces are included in the simulations. Three typical areas: the sextant arc, the Triplet/DX/D0 magnets, and the injection area, had been analyzed. Results, including helium discharge rates, helium inventory loss, and the resulting oxygen concentration in the RHIC tunnel area, are reported. Good agreement had been achieved when comparing the simulation results, a RHIC sector depressurization test measurement, and some simple analytical calculations.
 
 
TUP223 Cryogenic System for the Energy Recovery Linac and Vertical Test Facility at BNL cryomodule, cryogenics, cavity, vacuum 1235
 
  • R. Than, D.L. Lederle, L. Masi, P. Orfin, R. Porqueddu, V. Soria, T.N. Tallerico, P. Talty, Y. Zhang
    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.
A small cryogenic system and warm helium vacuum pumping system provides cooling to the Energy Recovery Linac's (ERL) cryomodules, a 5-cell cavity and an SRF gun, and a large Vertical Test Dewar. The system consist of a model 1660S PSI (KPS) plant, a 4000 liter storage dewar, subcooler, wet expander, 50 g/s main helium compressor and 170 m3 storage tank. A system description and operating plan is given of the cryogenic plant and cryomodules
 
 
TUP225 Overview of Recent Studies and Modifications Being Made to RHIC to Mitigate the Effects of a Potential Failure to the Helium Distribution System vacuum, cryogenics, factory, feedback 1241
 
  • J.E. Tuozzolo, D. Bruno, A. Di Lieto, G. Heppner, R. Karol, E.T. Lessard, C.J. Liaw, G.T. McIntyre, C. Mi, J. Reich, J. Sandberg, S.K. Seberg, L. Smart, T.N. Tallerico, R. Than, C. Theisen, R.J. Todd, R. Zapasek
    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.
In order to cool the superconducting magnets in RHIC, its helium refrigerator distributes 4.5 K helium throughout the tunnel via a series of distribution and return lines. The worst case for failure would be a release from the magnet distribution line, which operates at 3.5 to 4.5 atmospheres and contains the energized magnet bus. Should the bus insulation system fail or an electrical connection open, there is the potential for releasing up to 70 MJoules of stored energy. Studies were done to determine release rate of the helium and the resultant reduction in O2 concentration in the RHIC tunnel and service buildings. Equipment and components were also reviewed for reliability and the effects of 10 years of operations. Modifications were made to reduce the likelihood of failure and to reduce the amount of helium gas that could be released into tunnels and service buildings while personnel are present. This paper describes the issues reviewed, the steps taken, and remaining work to be done to reduce the hazards.
 
 
TUP228 Design of the EBIS Vacuum System vacuum, ion, solenoid, electron 1247
 
  • M. Mapes, L. Smart, D. Weiss
    BNL, Upton, Long Island, New York, USA
 
  At Brookhaven National Labratory the Electron Beam Ion Source (EBIS) is presently being commisioned. The EBIS will be a new heavy ion pre-injector for the Realativistic Heavy Ion Collider (RHIC). The new pre-injector has the potential for significant future intensity increases and can produce heavy ion beams of all species including uranium. The background pressure in the ionization region of the EBIS should be low enough that it does not produce a significant number of ions from background gas. The pressure in the regions of the electron gun and electron collector can be higher than in the ionization region provided there is efficient vacuum separation between the sections. For injection the ions must be accelerated to 100KV by pulsing the EBIS platform. All associated equipment including the vacuum equipment on the platform will be at a 100KV potential. The vacuum system design and the vacuum controls for the EBIS platform and transport system will be presented as well as the interface with the Booster Ring which has a pressure 10-11 Torr.  
 
TUP238 Development of an Integrated Field Measurement System (IFMS) for NSLS II undulator, insertion, HOM, pick-up 1271
 
  • A. Deyhim, S.W. Hartman, J.D. Kulesza
    Advanced Design Consulting, Inc, Lansing, New York, USA
 
  This paper describes the mechanical design, control instrumentation and software for the Integrated Field Measurement System (IFMS) for the Magnetic Measurement Lab for the National Synchrotron Light Source II (NSLS-II) project at Brookhaven National Laboratory. Insertion devices (IDs) at NSLS II need to be accurately surveyed using an integrated field measurement system prior to insertion into the storage ring and can also be used in the tunnel for final tuning of IDs. It is a fast and precise measurement system required in determining the ID magnetic field integrals. The design is a set of long coils supported by two 3-axis X-Y-Z precision linear and two precision rotary positioning stages. The PC is the primary control unit. Eight stepping motor control cards, eight drivers, one digital I/O board, one 6U PXI card, and one integrator are installed to perform remote control and data acquisition.  
 
TUP253 AGS Tune Jump Power Supply Design and Test power-supply, high-voltage, simulation, resonance 1298
 
  • J.-L. Mi, J.W. Glenn, H. Huang, I. Marneris, P.J. Rosas, J. Sandberg, Y. Tan, W. Zhang
    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.
A horizontal tune jump system has been installed to overcome the horizontal intrinsic spin resonances, which requires jumping the horizontal tune 0.04 units 82 times, 41 up and 41 down. Two quadruple magnets have been installed in AGS ring to do this. The pulsed magnet currents range from about 140 amps near injection to about 1400 amps late. Current pulse rise and fall times are around 100 micro-sec and flat tops time are around 4mS. These quadruples have separate supplies. This tune jump pulse power supply employees all semiconductor parts as the main switches. During dummy load and magnet testing, the test result showed that the power supply could meet the specification. This article will describe some detail of power supply simulation, design and testing. Some test waveform and pictures are presented in this paper.
 
 
TUP255 Solid-State Transmitter for a 2 MW Klystron klystron, cathode, high-voltage, monitoring 1304
 
  • M.K. Kempkes, M.P.J. Gaudreau, T.H. Hawkey, K. Schrock
    Diversified Technologies, Inc., Bedford, Massachusetts, USA
 
  Diversified Technologies, Inc. delivered a transmitter for a 2 MW, 500 MHz klystron manufactured by Communications and Power Industries, Inc. The transmitter design eliminates the need for a large pulse transformer; eliminates the crowbar for greater system availability and klystron reliability, and provides full control and monitoring of critical transmitter functions, settings, and fault diagnostics. The klystron beam power is generated by two high voltage power supplies, each capable of producing 150 kW CW power at 100 kV, with ~0.1% regulation. The transmitter can operate at lower average power in the unlikely event a single power supply goes off-line. The main solid-state switch, a series stack of commercially available IGBTs, delivers a range of HV pulsewidths to the klystron under normal operating conditions, and protects the klystron against arc damage. Should the current in the switch exceed a preset fault threshold value, the switch opens in ~ 1 μs to disconnect the high voltage from the klystron. In this paper, DTI will describe the architecture of the 2 MW klystron transmitter and its present status.  
 
TUP256 Affordable, Short Pulse Marx Modulator high-voltage, pick-up, status, linear-collider 1307
 
  • M.K. Kempkes, J.A. Casey, M.P.J. Gaudreau, R.A. Phillips
    Diversified Technologies, Inc., Bedford, Massachusetts, USA
  • J. Casey
    Rockfield Research, Inc. east, Winchester, Massachusetts, USA
 
  Funding: U.S. Department of Energy
Under a U.S. Department of Energy grant, Diversified Technologies, Inc. (DTI) is developing a short pulse, solid-state Marx modulator. The modulator is designed for high efficiency in the 100 kV to 500 kV range, for currents up to 500 A, pulse lengths of 0.2 to 5.0 μs, and risetimes <300 ns. Key objectives of the development effort are modularity and scalablity, combined with low cost, and ease of manufacture. For short-pulse modulators, this Marx topology provides a means to achieve fast risetimes and flattop control that are simply not available with hard switch or transformer-coupled topologies. In this paper, DTI will describe the new design and provide an update on progress.
 
 
TUP261 The ILC P2 Marx and Application of the Marx Topology to Future Accelerators klystron, power-supply, FEL, high-voltage 1313
 
  • M.A. Kemp, A.L. Benwell, C. Burkhart, J. Hugyik, R.S. Larsen, D.J. MacNair, K.J.P. Macken, M.N. Nguyen, J.J. Olsen
    SLAC, Menlo Park, California, USA
 
  Funding: Work supported by the US Department of Energy under contract DE-AC02-76SF00515.
The SLAC P2 Marx is under development for the ILC linac klystron modulator. Specifications are for an output of 120 kV, 140 A, 1.6 ms pulse width, 5 Hz pulse repetition frequency, and ± 0.5% flat-top. The SLAC P2 Marx builds upon the success of the P1 Marx, which is currently undergoing lifetime evaluation. While the P2 Marx’s target application is the ILC, characteristics of the Marx topology make it equally well-suited for different parameter ranges; for example, increased pulse repetition frequency, increased output current, longer pulse width, etc. Marx parameters such as the number of cells, cell capacitance, and component selection can be optimized for the application. This paper provides an overview of the P2 Marx development including design, fabrication progress, and test results for the modulator and sub-assemblies. High-availability features of the modulator such as the diagnostic/prognostic embedded control system and fault-adaptive automatic reconfiguration will be detailed. In addition, the scalability of the Marx topology to other long-pulse parameter ranges will be highlighted. Topology adaptations for several proposed accelerators will be presented.
 
 
TUP267 LANSCE Drift Tube Linac Water Control System Refurbishment EPICS, linac, drift-tube-linac, monitoring 1319
 
  • P.S. Marroquin, J.D. Bernardin, J.G. Gioia, J.A. Ortiz
    LANL, Los Alamos, New Mexico, USA
 
  Funding: Funding Agency: Work performed under the auspices of the U.S. Department of Energy, under contract DE-AC52-06NA25396.
There are several refurbishment projects underway at the Los Alamos National Laboratory LANSCE linear accelerator. Systems involved are: RF, water cooling, networks, diagnostics, timing, controls, etc. The Drift Tube Linac (DTL) portion of the accelerator consists of four DTL tanks, each with three independent water control systems. The systems are about 40 years old, use outdated and non-replaceable equipment and NIM bin control modules, are beyond their design life and provide unstable temperature control. Insufficient instrumentation and documentation further complicate efforts at maintaining system performance. Detailed design of the replacement cooling systems is currently in progress. Previous design experience on the SNS accelerator water cooling systems will be leveraged. Plans call for replacement of water piping, manifolds, pumps, valves, mix tanks, instrumentation (flow, pressure and temperature) and control system hardware and software. This presentation will focus on the control system design with specific attention on planned use of the National Instruments Compact RIO platform with the Experimental Physics and Industrial Control System (EPICS) software toolkit.
 
 
TUP276 Measurement of Thermal Dependencies of PBG Fiber Properties laser, simulation, acceleration, alignment 1343
 
  • R. Laouar, E.R. Colby, R.J. England, R.J. Noble
    SLAC, Menlo Park, California, USA
 
  Funding: Department Of Energy
Photonic crystal fibers (PCFs) represent a class of optical fibers which have a wide spectrum of applications in the telecom and sensing industries. Currently, the Advanced Accelerator Research Department at SLAC is developing photonic bandgap particle accelerators, which are photonic crystal structures with a central defect used to accelerate electrons and achieve high longitudinal electric fields. Extremely compact and less costly than the traditional accelerators, these structures can support higher accelerating gradients and will open a new era in high energy physics as well as other fields of science. Based on direct laser acceleration in dielectric materials, the so called photonic band gap accelerators will benefit from mature laser and semiconductor industries.
 
 
TUP278 Tuning Method for the 2π/3 Traveling Wave Structures coupling, beam-loading, impedance, linac 1349
 
  • A.S. Setty
    THALES, Colombes, France
 
  To build a constant gradient traveling wave structure, one must perform cold tests under a press in order to tune the different cells individually. For the tests to be valid, the test cells must be terminated by shorting planes located in planes of symmetry in which the electric field vector is normal in such a way that the standing wave "trapped" between them is an exact representation of the instantaneous traveling wave one wishes to study. For the TW structure, the cavities are put three by three under the press. We then try to reduce the contribution of "mixed cells" by adding to one wavelength at 2π/3 mode two-quarter wavelengths. This is possible when the end-cells mode at the same frequency is π/2 instead of 2π/3. These end cells are not included in the final assembly. The setting process will be analysed.  
 
TUP284 AGS Tune Jump System to Cross Horizontal Depolarization Resonances Overview resonance, power-supply, polarization, proton 1361
 
  • J.W. Glenn, L. A. Ahrens, Z. Altinbas, W. Fu, J.-L. Mi, P.J. Rosas, V. Schoefer, 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. Department of Energy.
Two partial snakes overcome the vertical depolarizing resonances in the AGS. But a new type of depolarizing intrinsic resonance from horizontal motion appeared. We reduce these using horizontal tune jumps timed to these resonances. We gain a factor of five in crossing rate with a tune jump of 0.04 in 100 micro-sec. Two quadrapoles, we described in 2009 *, pulse 42 times, the current matching beam energy. The power supplies for these quads will be described in this conference**. The controls for the Jump Quad system is based on a BNL designed Quad Function Generator. Two modules are used; one for timing, and one to supply reference voltages. Synchronization is provided by a proprietary serial bus, the Event Link. The AgsTuneJump application predicts the times of the resonances during the AGS cycle and calculates the power supply trigger times from externally collected tune and energy verses time data and the Low and High PS voltage functions from a voltage to current model of the power supply. The system was commissioned during runs 09 & 10. Beam effects are described elsewhere in this conference***. Details of improvements, operation and the feed forward software will be described.
* JW Glenn, et al “AGS Fast Spin Resonance,-” PAC-09
** JL Mi, et al “AGS Tune Jump Power-” these proceedings
*** L.A.Ahrens, et al "Recent RHIC Motivated Polarized-" these proceedings
 
 
TUP290 Progress on MICE RFCC Module for the MICE Experiment cavity, coupling, vacuum, EPICS 1370
 
  • A.J. DeMello, N. Andresen, M.A. Green, D. Li, S.P. Virostek, M.S. Zisman
    LBNL, Berkeley, California, USA
  • Y. Cao, S. Sun, L. Wang, L. Yin
    SINAP, Shanghai, People's Republic of China
  • A.B. Chen, X.K. Liu, H. Pan, F.Y. Xu
    ICST, Harbin, People's Republic of China
  • M. Reep, D.J. Summers
    UMiss, University, Mississippi, USA
 
  Funding: This work is supported by the Office of Science, United States Department of Energy under DOE contract DE-AC02-05CH11231.
We describe the recent progress on the design and fabrication of the RFCC (RF and Coupling Coil) module for the international Muon Ionization Cooling Experiment (MICE). The MICE cooling channel has two RFCC modules; each has four 201-MHz normal conducting RF cavities and one superconducting solenoid magnet. The magnet is designed to be cooled by three cryocoolers. Fabrication of the RF cavities is complete; design and fabrication of the magnets are in progress. The first magnet is expected to be finished by the end of 2011.
 
 
WEOAN1 Accelerator Timing Systems Overview optics, laser, kicker, FEL 1376
 
  • J. Serrano, P. Alvarez, M.M. Lipinski, T. Włostowski
    CERN, Geneva, Switzerland
 
  Timing systems are crucial ingredients for the successful operation of any particle accelerator complex. They are used not only to synchronize different processes but also to time-stamp and ensure overall coherency of acquired data. We describe fundamental time and frequency figures of merit and methods to measure them, and continue with a description of current synchronization solutions for different applications, precisions and geographical coverage, and some examples. Finally, we describe new trends in timing technology and applications.  
slides icon Slides WEOAN1 [1.122 MB]  
 
WEOBN1 Simultaneous Orbit, Tune, Coupling, and Chromaticity Feedback at RHIC feedback, coupling, betatron, injection 1394
 
  • M.G. Minty, A.J. Curcio, W.C. Dawson, C. Degen, R.L. Hulsart, Y. Luo, G.J. Marr, A. Marusic, K. Mernick, R.J. Michnoff, P. Oddo, V. Ptitsyn, G. Robert-Demolaize, T. Russo, V. Schoefer, C. Schultheiss, S. Tepikian, M. Wilinski
    BNL, Upton, Long Island, New York, USA
  • T. Satogata
    JLAB, Newport News, Virginia, USA
 
  Funding: Work supported by Brookhaven Science Associates, LLC under Contract No. DE-AC02-98CH10886 with the U.S. Department of Energy.
All physics stores at the Relativistic Heavy Ion Collider are now established using simultaneous orbit, tune, coupling, and energy feedback during beam injection, acceleration to full beam energies, during the “beta-squeeze” for establishing small beam sizes at the interaction points, and during removal of separation bumps to establish collisions. In this report we describe the major changes made to enable these achievements. The proof-of-principle for additional chromaticity feedback will also be presented.
 
slides icon Slides WEOBN1 [8.054 MB]  
 
WEOBN2 Real-Time Beam Control at the LHC feedback, diagnostics, coupling, dipole 1399
 
  • R.J. Steinhagen
    CERN, Geneva, Switzerland
 
  At the LHC, real-time feedback systems continually control the orbit, tune, coupling, and chromaticity. Reliable and precise control of these parameters is essential to avoid superconducting magnet quenches or damage to LHC components. The speaker will review the underlying principles and hardware, and describe experiences with these systems during LHC commissioning and operations.  
slides icon Slides WEOBN2 [5.475 MB]  
 
WEOBN3 BOY, A Modern Graphical Operator Interface Editor and Runtime EPICS, feedback, background, status 1404
 
  • X.H. Chen, K.-U. Kasemir
    ORNL, Oak Ridge, Tennessee, USA
 
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy
Taking advantage of modern graphical editor software technology, a new Operator Interface (OPI) editor and runtime - Best OPI, Yet (BOY) - was developed by the Control System Studio (CSS) collaboration. It uses the Eclipse Graphical Editor Framework (GEF) to provide modern graphical editor functions, which makes it easy and intuitive to edit OPIs. Combined with Javascript and configurable rules, it is also easy to create powerful OPIs with complicated client-side logic. By simply providing the name of a Process Variable (PV), it will automatically handle the network connections. The graphical layer is decoupled from the data connection layer, conceptually allowing BOY to connect to arbitrary data sources, with current support including EPICS Channel Access and simulation PVs. BOY is integrated with the CSS platform, which provides inter-operability with other CSS tools. Fundamentally, it could also be integrated with other Eclipse Rich Client Platform (RCP) applications due to its plugin mechanism. We have several screens deployed at the Spallation Neutron Source (SNS), where BOY has proven to be stable in support of SNS operation.
 
slides icon Slides WEOBN3 [3.461 MB]  
 
WEOBN4 Multipurpose Controller Based on a FPGA with EPICS Integration EPICS, monitoring, LLRF, low-level-rf 1407
 
  • P. Echevarria, I. Arredondo, N. Garmendia, H. Hassanzadegan, L. Muguira
    ESS Bilbao, Bilbao, Spain
  • D. Belver, M. del Campo
    ESS-Bilbao, Zamudio, Spain
  • V. Etxebarria, J. Jugo
    University of the Basque Country, Faculty of Science and Technology, Bilbao, Spain
 
  In this work a multipurpose configurable control system is presented. This controller is based on a high performance FPGA for a fast control connected to a Host PC which works as an EPICS server to allow a remote control. The communication between both parts is made by a register bank implemented in the FPGA and which is accessible by the Host PC by means of a Compact PCI bus. The initialization values, the numeric representation of the digital signals and the EPICS database are configured by an XML file. This control scheme has been prototyped for two applications: Low Level RF and Beam Position Monitoring. The former contains three digital loops to control the amplitude and phase of the RF supply and the geometry of the cavity. The latter processes the information from four capacitive buttons to calculate the position of the beam. In both systems, the necessary parameters for the digital processing of the acquired signals (using fast ADCs) and intermediate calculations are stored in the register bank connected to the cPCI bus. These systems are being developed for the ESS-Bilbao facility which will be built in Bilbao, Spain.  
slides icon Slides WEOBN4 [0.621 MB]  
 
WEOBN5 Concept and Architecture of the RHIC LLRF Upgrade Platform LLRF, collider, booster, target 1410
 
  • K.S. Smith, T. Hayes, F. Severino
    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 goal of the RHIC LLRF upgrade has been the development of a stand alone, generic, high performance, modular LLRF control platform, which can be configured to replace existing systems and to serve as a common platform for all new RF systems. The platform is also designed to integrate seamlessly into a distributed network based controls infrastructure, be easy to deploy, and to be useful in a variety of digital signal processing and data acquisition roles. Reuse of hardware, software and firmware has been emphasized to minimize development effort and maximize commonality of system components. System interconnection, synchronization and scaling is facilitated by a deterministic, high speed serial timing and data link, while standard intra and inter chassis communications utilize high speed, non-deterministic protocol based serial links. System hardware configuration is modular and flexible, based on a combination of a main carrier board which can host up to six custom or commercial daughter modules as required to implement desired functionality. This paper will provide an overview of the platform concept, architecture, features and benefits.
 
slides icon Slides WEOBN5 [31.462 MB]  
 
WEOBN6 LARP LHC 4.8 GHz Schottky System Initial Commissioning with Beam pick-up, proton, injection, ion 1413
 
  • R.J. Pasquinelli
    Fermilab, Batavia, USA
  • F. Caspers, O.R. Jones
    CERN, Geneva, Switzerland
  • A. Jansson
    ESS, Lund, Sweden
 
  The LHC Schottky system consists for four independent 4.8 GHz triple down conversion receivers with associated data acquisition systems. Each system is capable of measuring tune, chromaticity, momentum spread in either horizontal or vertical planes; two systems per beam. The hardware commissioning has taken place during the spring and summer of 2010. With nominal bunch beam currents of 1011 protons, the first incoherent Schottky signals were detected and analyzed. This paper will report on these initial commissioning results. A companion paper will report on the data analysis curve fitting and remote control user interface of the system.  
slides icon Slides WEOBN6 [27.117 MB]  
 
WEOCN2 A Non-Destructive Profile Monitor for High Intensity Beams electron, proton, gun, quadrupole 1438
 
  • W. Blokland, S.M. Cousineau
    ORNL, Oak Ridge, Tennessee, USA
 
  Funding: SNS is managed by UT-Battelle, LLC, under contract DE-AC05-00OR22725 for the U.S. Department of Energy.
A non-destructive profile monitor has been installed and commissioned in the accumulator ring of the Spallation Neutron Source (SNS). The SNS Ring accumulates high intensity proton bunches of up to 1.5·1014 protons with a typical peak current of over 50 A and a bunch length of about 0.7 us during a 1 ms cycle. The profile monitor consists of two systems, one for each plane, with electron guns, correctors, defectors, and quadrupoles to produce pulsed electron beams that scan through the proton bunch. The proton bunch EM fields alter the trajectory of the electrons and their projection on a fluorescent screen. The projection is analyzed to determine the transverse profile of the proton bunch. The speaker will describe the theory, hardware, software, analysis, results, and improvements to these electron scanners. The results include a comparison to wire scanner profiles of extracted ring beam.
 
slides icon Slides WEOCN2 [9.476 MB]  
 
WEOCS5 Experience of the Cryogenic System for Taiwan Light Source cryogenics, cavity, status, storage-ring 1466
 
  • F. Z. Hsiao, C.-S. Hwang
    NSRRC, Hsinchu, Taiwan
 
  In Taiwan light source a superconductive cavity and five superconductive magnets are installed in the storage ring. The cryogenic system provides liquid helium and liquid nitrogen with stable pressure. Failure events occurred on the components such as expansion turbine, compressor, and frequency inverter during the past years. A supervision system was developed to monitor the status of the cryogenic system and an automatic call out system was built to notify the operators when abnormal condition appears. To shorten the interruption period of liquid helium supply, the dewar keeps stable and continuous supply of liquid helium and the recovery compressor collets the evaporated helium gas from the cryostat for cases of several hours shutdown of the cryogenic system. Humidity, cleanliness and helium leak tightness are items necessary to be well controlled before connecting new components or application devices to the cryogenic system. The matching between system cooling capacity and heat load is achieved via adjustment of turbine speed, precooling temperature, compressor speed, and heater power.  
 
WEODN1 Overview of System Specifications for Bunch by Bunch Feedback Systems feedback, kicker, damping, coupling 1475
 
  • D. Teytelman
    Dimtel, San Jose, USA
 
  Bunch-by-bunch feedback control of coupled-bunch instabilities has become a ubiquitous feature of storage rings, light sources and colliders. Specifying the requirements for these systems demands knowledge of the instability sources and the accelerator operating parameter space. System requirements include the necessary loop gain and bandwidth, kick voltage, and the overall noise floor. Based on these specifications one can select the system BPMs, processing algorithms, power amplifiers and kickers and make tradeoffs of system cost against necessary performance. Through the use of analytical and experimental techniques this talk will illustrate practical and intelligent choices in this specification process. The approach involves experimental characterization of the accelerator at low or moderate beam currents. Measurements are used to calibrate a parameterized analytical beam dynamics model which can be then extrapolated to nominal beam currents with confidence. The speaker will present example results from several recent installations, highlighting the measurements, the model predictions, and the achieved system performance.  
slides icon Slides WEODN1 [1.755 MB]  
 
WEODN3 Performance Optimization for the LNLS Fast Orbit Feedback System feedback, power-supply, synchrotron, storage-ring 1485
 
  • D.O. Tavares, S.R. Marques
    LNLS, Campinas, Brazil
 
  The Brazilian Synchrotron Light Laboratory (LNLS) has recently commissioned a Fast Orbit Feedback System for its 1.37 GeV third-generation UVX Storage Ring. This paper presents the optimization work which was carried out using the new hardware capabilities. Well known strategies such as singular values conditioning for correction matrix, dynamic control by means of PID or IMC controllers and EVC (Eigenvector constrained) method for minimizing position error in source points were explored. The problem of actuator limitations (saturation and slew rate) was also investigated, providing a new front line for improving orbit stability through feedback.  
slides icon Slides WEODN3 [1.114 MB]  
 
WEODN4 NSLS-II Fast Orbit Feedback with Individual Eigenmode Compensation feedback, emittance, EPICS, storage-ring 1488
 
  • Y. Tian, L.-H. Yu
    BNL, Upton, Long Island, New York, USA
 
  This paper presents the NSLS-II fast orbit feedback system with individual eigenmode compensation. The fast orbit feedback system is a typical multiple-input and multiple-output (MIMO) system. Traditional singular value decomposition (SVD) based fast orbit feedback systems treat each eigenmode the same and the same compensation algorithm is applied to all the eigenmodes. In reality, a MIMO system will have different frequency responses for different eigenmodes and thus it is desirable to design different compensation for each eigenmode. The difficulty with this approach comes from the large amount of computation that needs to be done within the time budget of the orbit feedback system. We designed and implemented the NSLS-II fast orbit feedback (FOFB) system with individual eigenmode compensation by taking advantage of the parallel computation capability of field programmable gate array (FPGA) chips.  
slides icon Slides WEODN4 [1.064 MB]  
 
WEP079 Mathematical Models of Feedback Systems for Control of Intra-Bunch Instabilities Driven by E-Clouds and TMCI feedback, electron, simulation, proton 1621
 
  • C.H. Rivetta, J.D. Fox, T. Mastoridis, M.T.F. Pivi, O. Turgut
    SLAC, Menlo Park, California, USA
  • W. Höfle
    CERN, Geneva, Switzerland
  • R. Secondo, J.-L. Vay
    LBNL, Berkeley, California, USA
 
  Funding: Work supported by the U.S. Department of Energy under contract # DE-AC02-76SF00515 and the US LHC Accelerator Research Program (LARP).
The feedback control of intrabunch instabilities driven by E-Clouds or strong head-tail coupling (TMCI) requires sufficient bandwidth to sense the vertical position and drive multiple sections of a nanosecond scale bunch. These requirements impose challenges and limits in the design and implementation of the feedback system. This paper presents models for the feedback subsystems: receiver, processing channel, amplifier and kicker, that take into account their frequency response and limits. These models are included in multiparticle simulation codes (WARP/CMAD/Head-Tail) and reduced mathematical models of the bunch dynamics to evaluate the impact of subsystem limitations in the bunch stabilization and emittance improvement. With this realistic model of the hardware, it is possible to analyze and design the feedback system. This research is crucial to evaluate the performance boundary of the feedback control system due to cost and technological limitations. These models define the impact of spurious perturbations, noise and parameter variations or mismatching in the performance of the feedback system. The models are validated with simulation codes and measurements of lab prototypes.
 
 
WEP099 Numerical Solution for the Potential and Density Profile of a Thermal Equilibrium Sheet Beam space-charge, focusing, plasma, ion 1659
 
  • S.M. Lund
    LLNL, Livermore, California, USA
  • G. Bazouin
    LBNL, Berkeley, California, USA
 
  Funding: This research was performed under the auspices of the US DOE at the Lawrence Livermore and Lawrence Berkeley National Laboratories under contract numbers DE-AC52-07NA27344 and DE-AC02-05CH11231.
A one-dimensional Vlasov-Poisson model for sheet beams is presented to provide a simple framework for analysis of space-charge effects. Centroid and rms envelope equations including image charge effects are derived and reasonable parameter equivalences with commonly employed 2D transverse models of unbunched beams are established. This sheet beam model is applied to analyze several problems of fundamental interest. First, a sheet beam thermal equilibrium distribution in a continuous focusing channel is constructed and shown to have analogous properties to two- and three-dimensional thermal equilibrium models in terms of the equilibrium structure and Deybe screening properties. Second, the simpler formulation for sheet beams is exploited to explicitly calculate the distribution of particle oscillation frequencies within a thermal equilibrium beam. It is shown that as space-charge intensity increases, the frequency distribution becomes broad which suggesting robust stability properties for beams with strong space-charge.
 
 
WEP111 Beam Breakup in Dielectric Wakefield Accelerating Structures: Modeling and Experiments simulation, solenoid, wakefield, focusing 1689
 
  • P. Schoessow, C.-J. Jing, A. Kanareykin, A.L. Kustov
    Euclid TechLabs, LLC, Solon, Ohio, USA
  • A. Altmark
    LETI, Saint-Petersburg, Russia
  • W. Gai, J.G. Power
    ANL, Argonne, USA
 
  Funding: Work supported by USDOE SBIR program.
Beam breakup (BBU) effects resulting from parasitic wakefields limit considerably the intensity of the drive beam that can be transported through a dielectric accelerating structure and hence the accelerating field that can be achieved. We have been developing techniques to control BBU effects using a quadrupole channel or solenoid surrounding the wakefield device. We report here on the status of simulations and experiments on BBU and its mitigation, emphasizing an experiment at the Argonne Wakefield Accelerator facility using a 26 GHz dielectric wakefield device fitted with a solenoid to control BBU. We present calculations based on a particle-Green’s function beam dynamics code (BBU-3000) that we are developing. The code allows rapid, efficient simulation of BBU effects in advanced linear accelerators.
 
 
WEP152 Parallel Optimization of Beam-Beam Effects in High Energy Colliders luminosity, simulation, collider, beam-beam-effects 1770
 
  • J. Qiang, R.D. Ryne
    LBNL, Berkeley, California, USA
 
  Funding: Work supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231.
Beam-beam effects limit luminosity in high energy colliders. Parallel beam-beam simulation codes were developed to study those beam-beam effects and to help the collider design. In this paper, we will present a parallel optimization algorithm integrating together with the parallel beam-beam simulation to optimize the luminosity of the colliding beams. This algorithm is based on a differential evolutionary global optimization method and takes advantage of the two-level parallelization in both parallel search and parallel objective function evaluation. This significantly increases the scalability of the simulation on peta-scale supercomputers and reduces the time for finding the optimal working point.
 
 
WEP153 Simulation Results of a Feedback Control System to Damp Electron Cloud Single-Bunch Transverse Instabilities in the CERN SPS feedback, simulation, kicker, electron 1773
 
  • R. Secondo, J.-L. Vay, M. Venturini
    LBNL, Berkeley, California, USA
  • J.D. Fox, C.H. Rivetta
    SLAC, Menlo Park, California, USA
  • W. Höfle
    CERN, Geneva, Switzerland
 
  Funding: Work supported by the US-DOE under Contract DE-AC02-05CH11231 and the US-LHC Accelerator Research Program (LARP).
Transverse Single-Bunch Instabilities due to Electron Cloud effect are limiting the operation at high current of the SPS at CERN. Recently a high-bandwidth Feedback System has been proposed as a possible solution to stabilize the beam and is currently under study. We analyze the dynamics of the bunch actively damped with a simple model of the Feedback in the macro-particle code WARP, in order to investigate the limitations of the System such as the minimum amount of power required to maintain stability. We discuss the feedback model, report on simulation results and present our plans for further development of the numerical model.
 
 
WEP199 Estimation of Ecloud and TMCI Driven Vertical Instability Dynamics from SPS MD Measurements - Implications for Feedback Control feedback, simulation, injection, synchrotron 1861
 
  • O. Turgut, A. Bullitt, J.D. Fox, G. Ndabashimiye, C.H. Rivetta, M. Swiatlowski
    SLAC, Menlo Park, California, USA
  • W. Höfle, B. Salvant
    CERN, Geneva, Switzerland
  • R. Secondo
    LBNL, Berkeley, California, USA
 
  Funding: Work supported by the U.S. Department of Energy under contract # DE-AC02-76SF00515 and the US LHC Accelerator Research Program (LARP).
We present analysis of beam motion data obtained in high intensity SPS MD studies in 2009 and 2010. The single-bunch vertical E-cloud motion seen in parts of the bunch train after injection shows large tune shifts (roughly 0.02 above the 0.185 tune) developing between tail and head of unstable bunches. The unstable vertical motion has spectral content up to roughly 1.2 GHz and a quasi-periodic growth and decoherence relaxation oscillation effect is seen with time scales of hundred turns. Beam slice FFT and RMS techniques are illustrated to extract parameters important for the design of wide-band vertical feedback system, such as a growth rates of unstable motion, tune shifts within a single bunch and characterization of the bandwidth of the unstable structures within a bunch. We highlight the impact of synchrotron motion and injection transients on a proposed vertical processing channel. We present our MD plans including the beam driving process, developments in reduced model / identification techniques to extract dynamics from experimental and simulation data.
*J. Fox et al., ‘‘SPS Ecloud Instabilities - Analysis Of Machine Studies And Implications For Ecloud Feedback,'' IPAC'10, WEPEB052
 
 
WEP205 A Gap Clearing Kicker for Main Injector kicker, injection, booster, simulation 1870
 
  • I. Kourbanis, P. Adamson, J. Biggs, B.C. Brown, D. Capista, C.C. Jensen, G.E. Krafczyk, D.K. Morris, D.J. Scott, K. Seiya, S.R. Ward, G.H. Wu, M.-J. Yang
    Fermilab, Batavia, USA
 
  Funding: Operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy.
Fermilab Main Injector has been operating at high Beam Power Levels since 2008 when multi-batch slip stacking became operational. In order to increase the beam power even further we have to address the localized beam loss due to beam left over in the Injection Kicker Gap during slip stacking. A set of Gap Clearing Kickers that kick any beam left in the injection gap to the beam abort have been installed during the summer of 2009 and became operational in October 2010. The kicker performance and its effect on beam losses will be described.
 
 
WEP209 Reliability Study of the AIRIX Induction Accelerator over a Functioning Period of Ten Years (2000-2010) electron, vacuum, high-voltage, diagnostics 1882
 
  • H. Dzitko, A. Georges, B. Gouin, M. Mouillet
    CEA, Pontfaverger-Moronvilliers, France
 
  AIRIX is a high current (19 MeV, 2 kA) electron linear induction accelerator used as a 60 ns single shot X-ray source for hydrodynamic experiments. As single shot experiments are performed with the AIRIX facility, the best performances and a high reliability level must be met for each experiment. A high availability is also a key issue for the successful development of hydrotest projects. The AIRIX accelerator has been running for hydroshot experiments since 2000 and several thousands electron and X-ray beams have been produced. This paper outlines the reliability results of the AIRIX accelerator over a functioning period of ten years. Failure rates for each main subsystems are shown : injector, accelerating cells, high voltage generators, and measurement chains. We also give an overview of the most probable faults, with the associated occurrence rates, which can alter the X source of the AIRIX machine over this ten year period.  
 
WEP277 Operational Findings and Upgrade Plans on the Superconducting Electron Accelerator S-DALINAC recirculation, electron, linac, quadrupole 1999
 
  • F. Hug, C. Burandt, J. Conrad, R. Eichhorn, M. Kleinmann, M. Konrad, T. Kürzeder, P.N. Nonn, N. Pietralla, S.T. Sievers
    TU Darmstadt, Darmstadt, Germany
 
  Funding: DFG through SFB 634.
The S-DALINAC is a superconducting recirculating electron accelerator with a final energy of 130 MeV. It operates in cw at 3 GHz. It accelerates beams of either unpolarized or polarized electrons and is used as a source for nuclear- and astrophysical experiments at the university of Darmstadt since 1987. We will report on the operational findings, recent modifications and on the future upgrade plans: First results from the new digital rf control system, the injector current upgrade and the improved longitudinal working point will be presented. In addition, an overview of the future plans, namely installing an additional recirculation path and two scraper systems will be given.
 
 
THOAS3 Status of the Oak Ridge Spallation Neutron Source (SNS) RF Systems klystron, linac, rfq, neutron 2050
 
  • T.W. Hardek, M.T. Crofford, Y.W. Kang, M.F. Piller, A.V. Vassioutchenko
    ORNL, Oak Ridge, Tennessee, USA
  • S.W. Lee, M.E. Middendorf
    ORNL RAD, Oak Ridge, Tennessee, USA
 
  The SNS has been delivering production neutrons for five years with first beam delivered to the neutron target at the end of April 2006. On September 18, 2009 SNS officially reached 1 megawatt of beam on target marking the achievement of a decades-old dream of providing a U.S. megawatt class pulsed spallation source. The SNS is now routinely delivering 1 megawatt of beam power to the neutron target at over 85 percent of the scheduled beam time. The present effort is aimed at increasing availability eventually to 95 percent and gradually increasing the intensity to the 1.4 megawatt design level. While the RF systems have performed well since initial installation some improvements have been implemented. This paper provides a review of the SNS RF Systems, an overview of the performance of the various components and a detailed review of RF related issues addressed over the past several years.  
slides icon Slides THOAS3 [2.759 MB]  
 
THOCS1 Would >50 MV/m be Possible with Superconducting RF Cavities? cavity, accelerating-gradient, superconducting-RF, electron 2119
 
  • T. Tajima
    LANL, Los Alamos, New Mexico, USA
 
  Several laboratories are working on the development of thin-film superconductor technology to overcome the fundamental limit of ~50 MV/m accelerating gradient with niobium SRF cavities. Efforts at LANL attempt to enhance the sustainable surface magnetic field by coating thin layers of superconductors, such as MgB2 on top of niobium. The coating techniques being developed and the results of RF critical field and surface resistance measurements that were obtained in collaboration with other national laboratories, universities and industry will be presented.  
slides icon Slides THOCS1 [0.751 MB]  
 
THOCS4 RF Power Upgrade for CEBAF at Jefferson Laboratory klystron, solenoid, cavity, cryomodule 2127
 
  • A.J. Kimber, R.M. Nelson
    JLAB, Newport News, Virginia, USA
 
  Funding: Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177.
Jefferson Laboratory (JLab) is currently upgrading the 6GeV Continuous Electron Beam Accelerator Facility (CEBAF) to 12GeV. As part of the upgrade, RF systems will be added, bringing the total from 340 to 420. Existing RF systems can provide up to 6.5 kW of CW RF at 1497 MHZ. The 80 new systems will provide increased RF power of up to 13 kW CW each. Built around a newly designed and higher efficiency 13 kW klystron developed for JLab by L-3 Communications, each new RF chain is a completely revamped system using hardware different than our present installations. This paper will discuss the main components of the new systems including the 13 kW klystron, waveguide isolator, and HV power supply using switch-mode technology. Methodology for selection of the various components and results of initial testing will also be addressed.
 
slides icon Slides THOCS4 [3.364 MB]  
 
THOCS5 Resonance Control in SRF Cavities at FNAL cavity, LLRF, SRF, resonance 2130
 
  • Y.M. Pischalnikov, W. Schappert
    Fermilab, Batavia, USA
  • M. Scorrano
    INFN-Pisa, Pisa, Italy
 
  Funding: Work is supported by the U.S. Department of Energy
An adaptive Least Squares algorithm to control Lorentz force detuning in SRF cavities has been developed and tested in the HTS at FNAL. During open-loop tests in the FNAL HTS, the algorithm was able to reduce LFD in a 9-cell 1.3 GHz elliptical cavity operating at 35 MV/m from 600 Hz to less than 10 Hz during both the fill and the flattop. The algorithm was also able to adapt to changes in the gradient of the cavity and to changes in the pulse length.
 
slides icon Slides THOCS5 [3.572 MB]  
 
THP016 Design of an Achromatic and Uncoupled Medical Gantry for Radiation Therapy quadrupole, optics, dipole, radiation 2163
 
  • N. Tsoupas, D. Kayran, V. Litvinenko, W.W. MacKay
    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.
We are presenting the layout and the optics of a beam line to be used as a medical gantry in radiation therapy. The optical properties of the gantry’s beam line are such as to make the beam line achromatic and uncoupled. These two properties make the beam spot size, which is delivered and focused by the gantry, on the tumor of the patient, independent of the angular orientation of the gantry. In this paper we present the layout of the magnetic elements of the gantry, and also present the theoretical basis for the optics design of such a gantry.
* N. Tsoupas et. al. “Uncoupled achromatic tilted S-bend” Presented at the 11th Biennial European Particle Accelerator Conference, Genoa, Italy, June 23-27,2008
 
 
THP051 An Overview of Normal Conducting Radio Frequency Projects and Manufacturing Capabilities at Radiabeam Technologies, LLC linac, gun, simulation, radio-frequency 2214
 
  • R.B. Agustsson, S. Boucher, X.D. Ding, L. Faillace, P. Frigola, A.Y. Murokh, S. Storms
    RadiaBeam, Santa Monica, USA
 
  Radiabeam Technologies is currently designing, engineering and fabricating 8 different Normal Conducting Radio Frequency (NCRF) accelerating and diagnostic structures. These NCRF programs include compact X-band industrial systems, laboratory grade NCRF photoinjectors, deflecting cavities and High-Gradient structures. Nearly all aspects of these NCRF structures’ lifecycle are performed in house, including design, 3D electromagnetic and thermomechanical modeling, engineering, fabrication, cleaning and RF cold testing, tuning, and RF power testing. An overview of these varied projects along with references to more detailed publications presented in this conference are provided. Details concerning specific processes applicable to all of the above mentioned RF projects are also discussed.  
 
THP060 RHIC 12x150A Current Lead Temperature Controller: Design and Implementation monitoring, power-supply, target, cryogenics 2238
 
  • C. Mi, D. Bruno, N.M. Day, A. Di Lieto, G. Ganetis, K. Hamdi, G. Heppner, J.P. Jamilkowski, W. Louie, J. Sandberg, S.K. Seberg, C. Sirio, J.E. Tuozzolo, K.L. Unger
    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
There are 60 12×150A current leads distributed in 6 RHIC service buildings; each current lead delivers power supply current from room temperature to cryogenic temperature in RHIC. Due to the humid environment, condensation frequently occurs and ice was quickly formed during operation, especially during an extensive storage period. This condition generated warnings and alarms that personal had to respond to, in order to provide temporary solutions, to keep the machine operational. A temperature control system was designed to avoid such occasions. We will discuss design, implementation and some results of this design in this paper.
 
 
THP121 Open-source Software System for Multi-author Documents EPICS 2345
 
  • L. Emery
    ANL, Argonne, USA
 
  Funding: Work supported by U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under contract No. DE-AC02-06CH11357
An efficient means was developed to manage multi-author documents using software components not usually run together that are both freely available and free of cost: Concurrent Version Software (CVS), LaTeX typesetting software, and the Unix make utility. Together they solve the main problem with multi-author documents: losing track of "latest" version, tracking author contributions, and a strict enforcement of document format. APS has used this system for two large documents with about a dozen authors each: a 2007 white paper (150 pages) on a ERL proposal and a chapter (200 pages) of the APS Upgrade CDR. We stress the use of LaTeX because the plain-text format is amenable to version comparisons and the macro-based system allows last-minute global format changes. Several contributions from APS to this conference actually use this system.
 
 
THP173 Design of the SRF Driver ERL for the Jefferson Lab UV FEL FEL, wiggler, linac, quadrupole 2435
 
  • C. Tennant, S.V. Benson, G.H. Biallas, K. Blackburn, J.R. Boyce, D.B. Bullard, J.L. Coleman, C. Dickover, D. Douglas, F.K. Ellingsworth, P. Evtushenko, C.W. Gould, J.G. Gubeli, F.E. Hannon, D. Hardy, C. Hernandez-Garcia, K. Jordan, J.M. Klopf, J. Kortze, M. Marchlik, S.W. Moore, G. Neil, T. Powers, D.W. Sexton, M.D. Shinn, R.L. Walker, F.G. Wilson, S. Zhang
    JLAB, Newport News, Virginia, USA
 
  Funding: Support by DoE Contract DE-AC05-060R23177.
We describe the design of the SRF ERL providing the CW electron drive beam at the Jefferson Lab UV FEL. Based on the same 135 MeV linear accelerator as – and sharing portions of the recirculator with – the Jefferson Lab 10 kW IR Upgrade FEL, the UV driver ERL uses a novel bypass geometry to provide transverse phase space control, bunch length compression, and nonlinear aberration compensation (including correction of RF curvature effects) without the use of magnetic chicanes or harmonic RF. Stringent phase space requirements at the wiggler, low beam energy, high beam current, and use of a pre-existing facility and legacy hardware subject the design to numerous constraints. These are imposed not only by the need for both transverse and longitudinal phase space management, but also by the potential impact of collective phenomena (space charge, wakefields, beam break-up (BBU), and coherent synchrotron radiation (CSR)), and by interactions between the FEL and the accelerator RF system. This report addresses these issues and presents the accelerator design solution that now successfully supports FEL lasing.
 
 
THP217 Frequent Fill Top-Off Injection at SPEAR3 injection, feedback, linac, power-supply 2531
 
  • J.J. Sebek, S. Allison, S.M. Gierman, X. Huang, J.A. Safranek, J.F. Schmerge, K. Tian, C. Wermelskirchen
    SLAC, Menlo Park, California, USA
 
  Funding: Work supported by the U.S. Department of Energy under contract number DE-AC02-76-SF00515
SPEAR3 beam is now delivered to users in a "frequent fill" mode in which beam is injected into the storage ring, with beam-line shutters open, on a periodic schedule so that the beam current is kept constant to within 1% of its average value. This goal was achieved with the constraints of having the SPEAR3 injector run at very high reliability and ensuring that there would be no challenges to the beam containment system in this operational mode. This paper presents the accelerator development, the hardware changes, and the software developed to implement this operational mode.
 
 
THP222 Drive Laser System for the Advanced Photo-Injector Project at the LBNL laser, cathode, electron, emittance 2537
 
  • J. Feng, D. Filippetto, H.A. Padmore, F. Sannibale, R.P. Wells
    LBNL, Berkeley, California, USA
  • M. J. Messerly, M.A. Prantil
    LLNL, Livermore, California, USA
 
  Funding: This work was supported by the Director of the Office of Science of the US Department of Energy under Contract no. DEAC02-05CH11231.
The electron photo-gun of the Advanced Photo-injector EXperiment project (APEX) at the LBNL will be driven by a compact fiber laser for different photo-cathode experiments during the initial phase of the project. The fiber laser, developed at the Lawrence Livermore National Laboratory, is designed to deliver μJ/pulse at 1064 nm system that is frequency doubled to deliver light at 532nm with 1MHz repetition rate and 1ps pulse length optimized for photo-emission with multi-alkali antimonide cathodes. For Cs2Te and diamond amplifier cathodes, the 4th harmonic will be generated by doubling frequency again in a non-linear crystal. Due to the requirement of small emittance for the electron beam, the laser pulse will be shaped in space and time for 532nm and UV lights, in general with a constant intensity in cross section with a sharp radial cutoff, and elliptical or rectangular distribution in the longitudinal plane. Diagnostics of the laser beam itself and of the cathode will be integrated with techniques such as cross- correlation, streak camera, and virtual cathode imaging, not only to monitor the laser pulse but also to provide automated feedbacks.
 
 
THP225 Characterization and Suppression of the Electromagnetic Interference Induced Phase Shift in the JLab FEL Photo – Injector Advanced Drive Laser System FEL, laser, shielding, electron 2546
 
  • F.G. Wilson, D.W. Sexton, S. Zhang
    JLAB, Newport News, Virginia, USA
 
  The new drive laser for the photo-cathode gun used in the JLab FEL facility had been experiencing various phase shifts on the order of tens of degrees (>20° at 1497 MHz or >40ps) when changing the Advanced Drive Laser (ADL) micro-pulse frequencies. These phase shifts introduce multiple complications when trying to setup the accelerator for operation, ultimately inhibiting the robustness and overall performance of the FEL. Through rigorous phase measurements and systematic characterizations, we discovered the problems could be attributed to EMI coupling into the ADL phase control loop system, and subsequently resolved the issue of phase shift to within tenths of a degree (<0.5° at 1497 MHz or <1ps). The diagnostic method developed and the knowledge gained through the entire process will prove to be invaluable for future designs of similar systems.