Author: Findlay, A.
Paper Title Page
MOPS009 Probing Intensity Limits of LHC-type Bunches in the CERN SPS with Nominal Optics 610
 
  • B. Salvant, G. Adrian, D.J. Allen, O. Andujar, T. Argyropoulos, J. Axensalva, J. Baldy, H. Bartosik, S. Cettour Cave, F. Chapuis, J.F. Comblin, K. Cornelis, D.G. Cotte, K. Cunnington, H. Damerau, M. Delrieux, J.L. Duran-Lopez, A. Findlay, J. Fleuret, F. Follin, P. Freyermuth, H. Genoud, S.S. Gilardoni, A. Guerrero, S. Hancock, K. Hanke, O. Hans, R. Hazelaar, W. Höfle, L.K. Jensen, J. Kuczerowski, Y. Le Borgne, R. Maillet, D. Manglunki, S. Massot, E. Matli, G. Metral, B. Mikulec, E. Métral, J.-M. Nonglaton, E. Ovalle, L. Pereira, F.C. Peters, A. Rey, J.P. Ridewood, G. Rumolo, J.L. Sanchez Alvarez, E.N. Shaposhnikova, R.R. Steerenberg, R.J. Steinhagen, J. Tan, B. Vandorpe, E. Veyrunes
    CERN, Geneva, Switzerland
 
  Some of the up­grade sce­nar­ios of the high-lu­mi­nos­i­ty LHC re­quire large in­ten­si­ty per bunch from the in­jec­tor chain. Sin­gle bunch beams with in­ten­si­ties of up to 3.5 to 4·1011 p/b and nom­i­nal emit­tances were suc­cess­ful­ly pro­duced in the PS Com­plex and de­liv­ered to the SPS in 2010. This con­tri­bu­tion pre­sents re­sults of stud­ies with this new in­tense beam in the SPS to probe sin­gle bunch in­ten­si­ty lim­i­ta­tions with nom­i­nal gamma tran­si­tion. In par­tic­u­lar, the ver­ti­cal Trans­verse Mode Cou­pling In­sta­bil­i­ty (TMCI) thresh­old with low chro­matic­i­ty was ob­served at 1.6·1011 p/b for sin­gle nom­i­nal LHC bunch­es in the SPS. With in­creased ver­ti­cal chro­matic­i­ty, larg­er in­ten­si­ties could be in­ject­ed, stored along the flat bot­tom and ac­cel­er­at­ed up to 450 GeV/c. How­ev­er, sig­nif­i­cant loss­es and/or trans­verse emit­tance blow up were then ob­served. Lon­gi­tu­di­nal and trans­verse op­ti­miza­tion ef­forts in the PSB, PS and SPS were put in place to min­i­mize this beam degra­da­tion and suc­ceed­ed to ob­tain sin­gle 2.3·1011 p/b LHC type bunch­es with sat­is­fy­ing pa­ram­e­ters at ex­trac­tion of the SPS.  
 
WEPS020 Study of an Energy Upgrade of the CERN PS Booster 2526
 
  • K. Hanke, O. Aberle, M. E. Angoletta, W. Bartmann, S. Bartolome, C. Bertone, A. Blas, J. Borburgh, D. Bozzini, A.C. Butterworth, C. Carli, P. Dahlen, T. Dobers, A. Findlay, R. Folch, N. Gilbert, J. Hansen, T. Hermanns, S. Jensen, P. Le Roux, L.A. Lopez Hernandez, E. Mahner, A. Masi, B. Mikulec, Y. Muttoni, A. Newborough, D. Nisbet, M. Nonis, S. Olek, M.M. Paoluzzi, S. Pittet, B. Puccio, V. Raginel, I. Ruehl, J. Tan, B. Todd, W.J.M. Weterings, M. Widorski
    CERN, Geneva, Switzerland
 
  CERN’s LHC in­jec­tor chain will have to de­liv­er beams with ul­ti­mate bril­liance as the LHC is head­ing for in­creased lu­mi­nos­i­ty in the com­ing years. In order to over­come bot­tle­necks in the in­jec­tor chain, an in­crease of the beam trans­fer en­er­gy from the CERN Pro­ton Syn­chrotron Boost­er (PSB) to the Pro­ton Syn­chrotron (PS) has been in­ves­ti­gat­ed as a pos­si­ble up­grade sce­nario. This paper gives an overview of the tech­ni­cal so­lu­tions and sum­ma­rizes the con­clu­sions of the fea­si­bil­i­ty study.  
 
WEPS022 Ions for LHC: Performance of the Injector Chain 2529
 
  • D. Manglunki, M. E. Angoletta, P. Baudrenghien, G. Bellodi, A. Blas, T. Bohl, C. Carli, E. Carlier, S. Cettour Cave, M. Chanel, K. Cornelis, H. Damerau, A. Findlay, S.S. Gilardoni, S. Hancock, J.M. Jowett, D. Kuchler, S. Maury, E. Métral, S. Pasinelli, M. Schokker, G. Tranquille, B. Vandorpe, U. Wehrle, J. Wenninger
    CERN, Geneva, Switzerland
 
  The first LHC Pb ion run took place at 1.38 A TeV/c per beam in au­tumn 2010. After a short pe­ri­od of run­ning-in, the in­jec­tor chain was able to fill the col­lid­er with up to 137 bunch­es per ring, with an in­ten­si­ty of 108 Pb ions/bunch, about 50% high­er than the de­sign value. This yield­ed a lu­mi­nos­i­ty of 3E25 Hz/cm2, al­low­ing the ex­per­i­ments to ac­cu­mu­late just under 10 in­verse mi­cro­barn each dur­ing the four week run. We re­view the per­for­mance of the in­di­vid­u­al links of the in­jec­tor chain, and ad­dress the main is­sues lim­it­ing the LHC lu­mi­nos­i­ty, in view of reach­ing 1026 Hz/cm2 in 2011, and sub­stan­tial­ly be­yond when the LHC en­er­gy in­creas­es after the long shut­down in 2013-14.