Author: Boogert, S.T.
Paper Title Page
MOCL1 Beam Instrumentation at the Accelerator Test Facility 2 26
 
  • S.T. Boogert
    JAI, Egham, Surrey, United Kingdom
  • S.T. Boogert
    Royal Holloway, University of London, Surrey, United Kingdom
 
  The Accelerator Test Facility 2 (ATF2) is a scaled demonstrator system for final focus beam lines of linear high energy colliders. Four OTR (Optical Transition Radiation) monitors have been installed at the ATF2. Major characteristics is the fast measurement of projected (2D) and intrinsic (4D) emittances and the coupling corrections with skew quadrupole magnets at the upstream. The high resolution cavity beam position monitor (BPM) system is a part of the ATF2 diagnostics. Two types of cavity BPMs are used, C-band operating at 6.426 GHz, and S-band at 2.888 GHz with an increased beam aperture. The resolution of the C-band system with attenuators was determined to be approximately 250 nm and 1 μm for the S-band system. Without attenuation the best recorded C-band cavity resolution was 27 nm. A laser-wire transverse electron beam size measurement system has been constructed and operated at the ATF2 beam line at KEK. A special set of electron beam optics was developed to generate an approximately 1μm vertical focus at the laser-wire location. Systematic measurements of a micron beam size have been successfully executed.  
slides icon Slides MOCL1 [6.059 MB]  
 
MOPC27 Cavity Beam Position Monitor System for ATF2 120
 
  • S.T. Boogert
    Royal Holloway, University of London, Surrey, United Kingdom
  • S.T. Boogert, F.J. Cullinan, Y.I. Kim, A. Lyapin, J. Snuverink
    JAI, Egham, Surrey, United Kingdom
  • T. Tauchi, N. Terunuma, J. Urakawa
    KEK, Ibaraki, Japan
  • G.R. White
    SLAC, Menlo Park, California, USA
 
  The Accelerator Test Facility 2 (ATF2) in KEK, Japan, is a prototype scaled demonstrator system for the final focus required for a future high energy lepton linear collider. The ATF2 beam-line is instrumented with a total of 38 C- and S- band resonant cavity beam position monitors (CBPM) with associated mixer electronics and digitizers. The current status of the BPM system is described, including a study of the CBPM performance over a three week period, including systematic effects such as charge, bunch length and beam offset dependence. The BPM system is routinely used for beam based alignment, wakefield kick measurements and dispersion measurements, the operational experience and example measurements are also reported.  
 
TUPC19 First Beam Tests of a Prototype Cavity Beam Position Monitor for the CLIC Main Beam 411
 
  • F.J. Cullinan, S.T. Boogert, A. Lyapin, J.R. Towler
    JAI, Egham, Surrey, United Kingdom
  • W. Farabolini, T. Lefèvre, L. Søby, M. Wendt
    CERN, Geneva, Switzerland
 
  Beam position monitors (BPMs) throughout the CLIC (Compact Linear Collider) main linac and beam delivery system must routinely operate at 50 nm resolution and be able to make multiple position measurements within a single 156 ns long bunch train. A prototype cavity beam position monitor, designed to demonstrate this performance, has been tested on the probe beamline of CTF3 (the CLIC Test Facility). Sensitivity measurements of the dipole mode position cavity and of the monopole mode reference cavity have been made. The characteristics of signals from short and long bunch trains and the dominant systematic effects have also been studied.  
 
TUPC20 Technologies and R&D for a High Resolution Cavity BPM for the CLIC Main Beam 415
 
  • J.R. Towler, T. Lefèvre, L. Søby, M. Wendt
    CERN, Geneva, Switzerland
  • S.T. Boogert, F.J. Cullinan, A. Lyapin
    JAI, Egham, Surrey, United Kingdom
 
  The Main Beam (MB) LINAC of the Compact Linear Collider (CLIC) requires a beam orbit measurement system with a high spatial (50 nm) and high temporal (50 ns) resolution to resolve the beam position within the 156 ns long bunch train, traveling on an energy-chirped, minimum dispersive trajectory. A 15 GHz prototype cavity BPM has been commissioned in the probe beam-line of the CTF3 CLIC Test Facility. The performance and technical details of this prototype installation are discussed in this paper, including the 15 GHz analog down-converter, the data acquisition and the control electronics and software. An R&D outlook is given for the next steps, which requires a system of 3 cavity BPMs to investigate the full resolution potential.  
 
TUPC22 Cavity Beam Position Monitor in Multiple Bunch Operation for the ATF2 Interaction Point Region 419
 
  • Y.I. Kim, D.R. Bett, N. Blaskovic Kraljevic, S.T. Boogert, P. Burrows, G.B. Christian, M.R. Davis, A. Lyapin, C. Perry
    JAI, Oxford, United Kingdom
  • J.C. Frisch, D.J. McCormick, J. Nelson, G.R. White
    SLAC, Menlo Park, California, USA
  • Y. Honda, T. Tauchi, N. Terunuma, J. Urakawa
    KEK, Ibaraki, Japan
 
  The Accelerator Test Facility 2 (ATF2) at KEK, Japan, is a scaled test beam line for the international linear collider (ILC) final focus system. There are two goals: firstly, to demonstrate focusing to 37 nm vertical beam size; secondly, to achieve a few nanometer level beam orbit stability at the focus point (the Interaction Point (IP)) in the vertical plane. High-resolution beam position monitors around the IP area (IPBPMs) have been developed in order to measure the electron beam position in that region with a resolution of a few nanometers in the vertical plane. Currently, the standard operation mode at ATF2 is single bunch, however, multiple bunch operation with a bunch spacing similar to the one foreseen for the ILC (around 300 ns) is also possible. IPBPMs have a low Q value resulting in a decay time of about 30 ns, and so should be able to measure the beam position of individual bunches without any significant performance degradation. The IPBPMs in the ATF2 extraction beam line have been tested in multibunch regime. This paper analyses the signals, processing methods and results for this mode.  
poster icon Poster TUPC22 [1.050 MB]  
 
WEPC46 Beam Delivery Simulation (BDSIM): A Geant4 Based Toolkit for Diagnostics and Loss Simulation 799
 
  • S.T. Boogert
    Royal Holloway, University of London, Surrey, United Kingdom
  • S.T. Boogert, S.M. Gibson, R. Kwee-Hinzmann, L.J. Nevay, J. Snuverink
    JAI, Egham, Surrey, United Kingdom
  • L.C. Deacon
    CERN, Geneva, Switzerland
 
  BDSIM is a Geant4 and C++ based particle tracking code which seamlessly tracks particles in accelerators and particle detectors, including the full range of particle interaction physics processes in Geant4. The code has been used to model the backgrounds in the International Linear Collider (ILC), Compact Linear Collider (CLIC), Accelerator Test Facility 2 (ATF2) and more recently the Large Hadron Collider (LHC). This paper outlines the current code and possible example applications and presents a roadmap for future developments.  
 
FRWAJ4
Experience on the ATF2 Cavity BPM System  
 
  • S.T. Boogert
    JAI, Egham, Surrey, United Kingdom
  • S.T. Boogert
    Royal Holloway, University of London, Surrey, United Kingdom
 
  Steward focused on the ATF2 cavity BPM relevant parts of his IBIC ATF2 beam diagnostics presentation. He summarized the experience on the BPM system over long operational periods, e.g. calibration, drifts, but discussed also the problems of large beam offsets, which are limiting the resolution. Of particular interest was his comparison of calculated and measured wakefield effects.  
slides icon Slides FRWAJ4 [0.299 MB]  
 
MOPC27 Cavity Beam Position Monitor System for ATF2 120
 
  • S.T. Boogert
    Royal Holloway, University of London, Surrey, United Kingdom
  • S.T. Boogert, F.J. Cullinan, Y.I. Kim, A. Lyapin, J. Snuverink
    JAI, Egham, Surrey, United Kingdom
  • T. Tauchi, N. Terunuma, J. Urakawa
    KEK, Ibaraki, Japan
  • G.R. White
    SLAC, Menlo Park, California, USA
 
  The Accelerator Test Facility 2 (ATF2) in KEK, Japan, is a prototype scaled demonstrator system for the final focus required for a future high energy lepton linear collider. The ATF2 beam-line is instrumented with a total of 38 C- and S- band resonant cavity beam position monitors (CBPM) with associated mixer electronics and digitizers. The current status of the BPM system is described, including a study of the CBPM performance over a three week period, including systematic effects such as charge, bunch length and beam offset dependence. The BPM system is routinely used for beam based alignment, wakefield kick measurements and dispersion measurements, the operational experience and example measurements are also reported.  
 
MOPF16 Sub-Micrometre Resolution Laserwire Transverse Beam Size Measurement System 243
 
  • L.J. Nevay
    JAI, Egham, Surrey, United Kingdom
  • A.S. Aryshev, N. Terunuma, J. Urakawa
    KEK, Ibaraki, Japan
  • S.T. Boogert, P. Karataev, K.O. Kruchinin
    Royal Holloway, University of London, Surrey, United Kingdom
  • L. Corner, R. Walczak
    Oxford University, Physics Department, Oxford, Oxon, United Kingdom
 
  The laserwire system at the Accelerator Test Facility 2 (ATF2) is a transverse beam profile measurement system capable of measuring a micrometre-size electron beam. We present recent results demonstrating a measured vertical size of 1.16 ± 0.06 μm and a horizontal size of 110.1 ± 3.8 μm. Due to the high aspect ratio of the electron beam, the natural divergence of the tightly focussed laser beam across the electron beam width requires the use of the full overlap integral to deconvolve the scans. For this to be done accurately, the propagation of the 150 mJ, 167 ps long laser pulses was precisely measured at a scaled virtual interaction point.  
 
WEAL2 Extremely Low Emittance Beam Size Diagnostics with Sub-Micrometer Resolution Using Optical Transition Radiation 615
 
  • K.O. Kruchinin, S.T. Boogert, P. Karataev, L.J. Nevay
    Royal Holloway, University of London, Surrey, United Kingdom
  • A.S. Aryshev, M.V. Shevelev, N. Terunuma, J. Urakawa
    KEK, Ibaraki, Japan
  • B. Bolzon
    The University of Liverpool, Liverpool, United Kingdom
  • B. Bolzon, T. Lefèvre, S. Mazzoni
    CERN, Geneva, Switzerland
 
  Transverse electron beam diagnostics is crucial for stable and reliable operation of the future electron-positron linear colliders such as CLIC or Higgs Factory. The-state-of-the-art in transverse beam diagnostics is based on the laser-wire technology. However, it requires a high power laser significantly increases the cost of the laser-wire system. Therefore, a simpler and relatively inexpensive method is required. A beam profile monitor based on Optical Transition Radiation (OTR) is very promising. The resolution of conventional OTR monitor is defined by a root-mean-square of the so-called Point Spread Function (PSF). In optical wavelength range the resolution is diffraction limited down to a few micrometers. However, in * we demonstrated that the OTR PSF has a structure which visibility can be used to monitor vertical beam size with sub-micrometer resolution. In this report we shall represent the recent experimental results of a micron-scale beam size measurement. We shall describe the entire method including calibration procedure, new analysis, and calculation of uncertainties. We shall discuss the hardware status and future plans.
* P. Karataev et al., Physical Review Letters 107, 174801 (2011).
 
slides icon Slides WEAL2 [5.120 MB]  
 
WEPC46 Beam Delivery Simulation (BDSIM): A Geant4 Based Toolkit for Diagnostics and Loss Simulation 799
 
  • S.T. Boogert
    Royal Holloway, University of London, Surrey, United Kingdom
  • S.T. Boogert, S.M. Gibson, R. Kwee-Hinzmann, L.J. Nevay, J. Snuverink
    JAI, Egham, Surrey, United Kingdom
  • L.C. Deacon
    CERN, Geneva, Switzerland
 
  BDSIM is a Geant4 and C++ based particle tracking code which seamlessly tracks particles in accelerators and particle detectors, including the full range of particle interaction physics processes in Geant4. The code has been used to model the backgrounds in the International Linear Collider (ILC), Compact Linear Collider (CLIC), Accelerator Test Facility 2 (ATF2) and more recently the Large Hadron Collider (LHC). This paper outlines the current code and possible example applications and presents a roadmap for future developments.  
 
FRWAJ4
Experience on the ATF2 Cavity BPM System  
 
  • S.T. Boogert
    JAI, Egham, Surrey, United Kingdom
  • S.T. Boogert
    Royal Holloway, University of London, Surrey, United Kingdom
 
  Steward focused on the ATF2 cavity BPM relevant parts of his IBIC ATF2 beam diagnostics presentation. He summarized the experience on the BPM system over long operational periods, e.g. calibration, drifts, but discussed also the problems of large beam offsets, which are limiting the resolution. Of particular interest was his comparison of calculated and measured wakefield effects.  
slides icon Slides FRWAJ4 [0.299 MB]