Author: Arnaudon, L.
Paper Title Page
MOPC054 The LHC RF System - Experience with Beam Operation 202
 
  • P. Baudrenghien, M. E. Angoletta, T. Argyropoulos, L. Arnaudon, J. Bento, T. Bohl, O. Brunner, A.C. Butterworth, E. Ciapala, F. Dubouchet, J. Esteban Muller, D.C. Glenat, G. Hagmann, W. Höfle, D. Jacquet, M. Jaussi, S. Kouzue, D. Landre, J. Lollierou, P. Maesen, P. Martinez Yanez, T. Mastoridis, J.C. Molendijk, C. Nicou, J. Noirjean, G. Papotti, A.V. Pashnin, G. Pechaud, J. Pradier, J. Sanchez-Quesada, M. Schokker, E.N. Shaposhnikova, D. Stellfeld, J. Tückmantel, D. Valuch, U. Wehrle, F. Weierud
    CERN, Geneva, Switzerland
 
  The LHC RF system commissioning with beam and physics operation for 2010 and 2011 are presented. It became clear in early 2010 that RF noise was not a lifetime limiting factor: the crossing of the much feared 50 Hz line for the synchrotron frequency did not affect the beam. The broadband LHC RF noise is reduced to a level that makes its contribution to beam diffusion in physics well below that of Intra Beam Scattering. Capture losses are also under control, at well below 0.5%. Longitudinal emittance blow-up, needed for ramping of the nominal intensity single bunch, was rapidly commissioned. In 2011, 3.5 TeV/beam physics has been conducted with 1380 bunches at 50 ns spacing, corresponding to 55% of the nominal current. The intensity per bunch (1.3 ·1011 p) is significantly above the nominal 1.15 ·1011. By August 2011 the LHC has accumulated more than 2 fb-1 integrated luminosity, well in excess of the 1 fb-1 target for 2011.  
 
TUOAA03 The Linac4 Project at CERN 900
 
  • M. Vretenar, L. Arnaudon, P. Baudrenghien, C. Bertone, Y. Body, J.C. Broere, O. Brunner, M.C.L. Buzio, C. Carli, F. Caspers, J.-P. Corso, J. Coupard, A. Dallocchio, N. Dos Santos, R. Garoby, F. Gerigk, L. Hammouti, K. Hanke, M.A. Jones, I. Kozsar, J.-B. Lallement, J. Lettry, A.M. Lombardi, L.A. Lopez Hernandez, C. Maglioni, S.J. Mathot, S. Maury, B. Mikulec, D. Nisbet, C. Noels, M.M. Paoluzzi, B. Puccio, U. Raich, S. Ramberger, C. Rossi, N. Schwerg, R. Scrivens, G. Vandoni, J. Vollaire, S. Weisz, Th. Zickler
    CERN, Geneva, Switzerland
 
  As the first step of a long-term programme aiming at an increase in the LHC luminosity, CERN is building a new 160 MeV H linear accelerator, Linac4, to replace the ageing 50 MeV Linac2 as injector to the Proton-Synchrotron Booster (PSB). Linac4 is an 86-m long normal-conducting linac made of an H source, a Radio Frequency Quadrupole (RFQ), a chopping line and a sequence of three accelerating structures: a Drift-Tube Linac (DTL), a Cell-Coupled DTL (CCDTL) and a Pi-Mode Structure (PIMS). The civil engineering has been recently completed, and construction of the main accelerator components has started with the support of a network of international collaborations. The low-energy section up to 3 MeV including a 3-m long 352 MHz RFQ entirely built at CERN is in the final construction phase and is being installed on a dedicated test stand. The present schedule foresees beam commissioning of the accelerator in the new tunnel in 2013/14; the moment of connection of the new linac to the CERN accelerator chain will depend on the LHC schedule for long shut-downs.  
slides icon Slides TUOAA03 [10.347 MB]