TUP1WA —  WG-A   (19-Jun-18   14:00—15:30)
Chair: G. Franchetti, GSI, Darmstadt, Germany
Paper Title Page
High Intensity Proton Studies at RAL  
  • C.R. Prior
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  This talk is about High Intensity Proton Studies at RAL.  
slides icon Slides TUP1WA01 [27.949 MB]  
TUP1WA02 Fixed Field Accelerators and Space Charge Modeling -1
  • A. Adelmann
    PSI, Villigen PSI, Switzerland
  • C.T. Rogers
    STFC/RAL/ISIS, Chilton, Didcot, Oxon, United Kingdom
  • S.L. Sheehy
    STFC/RAL/ASTeC, Chilton, Didcot, Oxon, United Kingdom
  The efforts of the Fixed Field Accelerators FFA (formerly known as FFAG accelerators) community to address the high intensity challenge are reviewed. Starting from analytic estimates and linear models for space charge computation, the current possibilities of precise 3D models for start to end modeling are discussed.  
slides icon Slides TUP1WA02 [9.488 MB]  
TUP1WA03 Beam Instabilities After Injection to the LHC -1
  • H. Timko, T. Argyropoulos, I. Karpov, E.N. Shaposhnikova
    CERN, Geneva, Switzerland
  Long-lasting phase oscillations have been observed at injection into the LHC since its first start-up with beam. These oscillations, however, were not leading to noticeable losses or blow-up in operation, and were therefore not studied in detail. In 2017, dedicated measurements with high-intensity bunches revealed that oscillations can lead to losses even slightly below the baseline intensity for the high-luminosity upgrade of the LHC. For the first time, high-resolution bunch profile acquisitions were triggered directly at injection and the formation of large-amplitude non-rigid dipole oscillations was observed on a turn-by-turn basis. First simulations can reproduce this instability via bunch filamentation that takes place after injection, depending on the mismatch between the bunch and bucket size in momentum at injection.  
slides icon Slides TUP1WA03 [2.166 MB]