Author: Baudrenghien, P.
Paper Title Page
TUPAB256 Investigation of Damping Effects of the Crab Cavity Noise Induced Emittance Growth 2054
 
  • N. Triantafyllou, L.R. Carver, A. Wolski
    The University of Liverpool, Liverpool, United Kingdom
  • F. Antoniou, H. Bartosik, P. Baudrenghien, X. Buffat, R. Calaga, Y. Papaphilippou, N. Triantafyllou
    CERN, Meyrin, Switzerland
  • L.R. Carver
    ESRF, Grenoble, France
  • T. Mastoridis
    CalPoly, San Luis Obispo, California, USA
 
  Crab cavities will be installed at the two main interaction points (IP1 and IP5) of the High Luminosity LHC (HL-LHC) in order to minimize the geometric reduction of the luminosity due to the crossing angle. Two prototype crab cavities have been installed into the SPS machine and were tested with a proton beam in 2018, to study the expected emittance growth induced by RF noise. The measured emittance growth was found to be a factor 2-3 lower than predicted from the available analytical and computational models. Damping mechanisms from the transverse impedance, which is not included in the available theories, are studied as a possible explanation for the observed discrepancy.  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-TUPAB256  
About • paper received ※ 18 May 2021       paper accepted ※ 18 June 2021       issue date ※ 23 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)  
 
THPAB200 Cavity Control Modelling for SPS-to-LHC Beam Transfer Studies 4168
 
  • L.E. Medina Medrano, T. Argyropoulos, P. Baudrenghien, H. Timko
    CERN, Meyrin, Switzerland
 
  Funding: Research supported by the HL-LHC project.
To accurately simulate injection losses in the LHC and the High-Luminosity LHC era, a realistic beam distribution model at SPS extraction is needed. To achieve this, the beam-loading compensation by the SPS cavity controller has to be included, as it modulates the bunch positions with respect to the rf buckets. This dynamic cavity control model also allows generating a more realistic beam halo, from which the LHC injection losses will mainly originate. In this paper, the implementation of the present SPS cavity controller in CERN’s Beam Longitudinal Dynamics particle tracking code is described. Just like in the machine, the feedback and feedforward controls are included in the simulation model, as well as the generator-beam-cavity interaction. Benchmarking against measurements of the generated beam distributions at SPS extraction are presented.
 
poster icon Poster THPAB200 [4.164 MB]  
DOI • reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2021-THPAB200  
About • paper received ※ 18 May 2021       paper accepted ※ 27 July 2021       issue date ※ 26 August 2021  
Export • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)