Author: Bartosik, H.
Paper Title Page
MOPPD059 Proposal of a Dummy Septum to Mitigate Ring Irradiation for the CERN PS Multi-Turn Extraction 499
  • M. Giovannozzi, H. Bartosik, D. Bodart, J. Borburgh, R.J. Brown, S. Damjanovic, S.S. Gilardoni, B. Goddard, C. Hernalsteens, M. Hourican, M. Widorski
    CERN, Geneva, Switzerland
  High activation of the magnetic extraction septum of the CERN PS machine was observed due to the losses of the continuous beam extracted via the Multi-Turn Extraction (MTE) method. The resulting activation is however incompatible with safe operation so a mitigation measure was required and found, namely the installation of a passive dummy septum to protect the actual one seems to provide the required reduction in activation in the extraction area. The shielded dummy septum is intended to absorb particles during the rise time of the MTE extraction kickers, avoiding the beam impact on the blade of the active magnetic extraction septum. The principle of the proposed modifications of the PS layout will be presented together with the studies aimed at finalising the new configuration.  
WEPPR072 Increasing Instability Thresholds in the SPS by Lowering Transition Energy 3096
  • H. Bartosik, G. Arduini, T. Argyropoulos, T. Bohl, S. Cettour-Cave, K. Cornelis, J. Esteban Muller, W. Höfle, Y. Papaphilippou, G. Rumolo, B. Salvant, E.N. Shaposhnikova
    CERN, Geneva, Switzerland
  A new optics for the SPS with lower transition energy was tested experimentally during 2010-2011, showing a significant increase of the single bunch instability thresholds at injection, due to the 3-fold increase of the slip factor. This paper summarizes the series of performed machine studies for different LHC bunch structures and intensities. In particular, the search of the TMCI threshold in the new optics is presented. Observations on the longitudinal multi-bunch stability are compared between the nominal and the low-transition optics. Finally, optics variants with higher vertical tunes are discussed, which can allow to further increase the TMCI and vertical instability thresholds by reducing the vertical beta function.  
THPPP012 Performance of the CERN Heavy Ion Production Complex 3752
  • D. Manglunki, M. E. Angoletta, H. Bartosik, G. Bellodi, A. Blas, T. Bohl, C. Carli, E. Carlier, S. Cettour Cave, K. Cornelis, H. Damerau, I. Efthymiopoulos, A. Findlay, S.S. Gilardoni, S. Hancock, J.M. Jowett, D. Kuchler, S. Maury, M. O'Neil, Y. Papaphilippou, S. Pasinelli, R. Scrivens, G. Tranquille, B. Vandorpe, U. Wehrle, J. Wenninger
    CERN, Geneva, Switzerland
  The second LHC ion run took place at 1.38 A TeV/c per beam in autumn 2011; more than 100 inverse microbarns was accumulated by each of the experiments. In addition, the LHC injector chain delivered primary Pb and secondary Be ion beams to fixed target experiments in the North Area. This paper presents the current performance of the heavy ion production complex, and prospects to further improve it in the near future.