Author: Alves, D.
Paper Title Page
MOCO03 Estimation of Longitudinal Profiles of Ion Bunches in the LHC Using Schottky-Based Diagnostics 44
 
  • K. Łasocha, D. Alves
    CERN, Meyrin, Switzerland
 
  The Large Hadron Collider (LHC) Schottky monitors have been designed to measure various parameters of relevance to beam quality, namely tune, momentum spread and chromaticity. We present another application of this instrument - the evaluation of longitudinal bunch profiles. The relation between the distribution of synchrotron amplitudes within the bunch population and the longitudinal bunch profile is derived from probabilistic principles. Our approach, limited to bunched beams with no intra-bunch coherent motion, initially fits the cumulative power spectral density of acquired Schottky spectra with the underlying distribution of synchrotron amplitudes. The result of this fit is then used to reconstruct the bunch profile using the derived model. The results obtained are verified by a comparison with measurements from the LHC Wall Current Monitors.  
slides icon Slides MOCO03 [48.066 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-MOCO03  
About • paper received ※ 04 September 2019       paper accepted ※ 08 September 2019       issue date ※ 10 November 2019  
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TUPP034 Analysis of Quadrupolar Measurements for Beam Size Determination in the LHC 392
 
  • D. Alves, M. Gąsior, T. Lefèvre
    CERN, Meyrin, Switzerland
 
  Due to limitations with non-invasive beam size diagnostics in the LHC, particularly during the energy ramp, there has been an interest to explore quadrupolar-based measurements for estimating the transverse beam size, and hence determining the transverse emittance. This technique is especially attractive as it is completely passive and can use the existing beam position instrumentation. In this work, we perform an analysis of this method and present recent measurements taken during energy ramps. Quadrupolar-based measurements are compared with wire-scanner measurements and a calibration strategy is proposed to overcome present limitations.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-TUPP034  
About • paper received ※ 03 September 2019       paper accepted ※ 09 September 2019       issue date ※ 10 November 2019  
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THAO01 Cherenkov Diffraction Radiation as a tool for beam diagnostics 658
 
  • T. Lefèvre, D. Alves, M. Bergamaschi, A. Curcio, O.R. Jones, R. Kieffer, S. Mazzoni, N. Mounet, A. Schlogelhofer, E. Senes
    CERN, Geneva, Switzerland
  • M. Apollonio, L. Bobb
    DLS, Oxfordshire, United Kingdom
  • A. Aryshev, N. Terunuma
    KEK, Ibaraki, Japan
  • M.G. Billing, Y.L. Bordlemay Padilla, J.V. Conway, J.P. Shanks
    Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
  • V.V. Bleko, S.Yu. Gogolev, A.S. Konkov, J.S. Markova, A. Potylitsyn, D.A. Shkitov
    TPU, Tomsk, Russia
  • K.V. Fedorov, D.M. Harryman, P. Karataev, K. Lekomtsev
    JAI, Egham, Surrey, United Kingdom
  • J. Gardelle
    CEA, LE BARP cedex, France
  • K. Łasocha
    Marian Smoluchowski Institute of Physics, Jagiellonian University, Kraków, Poland
 
  During the last three years, the emission of Cherenkov Diffraction Radiation (ChDR), appearing when a relativistic charged particle moves in the vicinity of a dielectric medium, has been investigated with the aim of providing non-invasive beam diagnostics. ChDR has very interesting properties, with a large number of photons emitted in a narrow and well-defined solid angle, providing excellent conditions for detection with very little background. This contribution will present a collection of recent beam measurements performed at several facilities such as the Cornell Electron Storage Ring, the Advanced Test Facility 2 at KEK, the Diamond light source in the UK and the CLEAR test facility at CERN. Those results, complemented with simulations, suggest that the use of both incoherent and coherent emission of Cherenkov diffraction radiation could open up new beam instrumentation possibilities for relativistic charged particle beams.  
slides icon Slides THAO01 [10.658 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IBIC2019-THAO01  
About • paper received ※ 09 September 2019       paper accepted ※ 10 September 2019       issue date ※ 10 November 2019  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)