Author: Cettour Cave, S.
Paper Title Page
TUPME046 Performance of SPS Low Transition Energy Optics for LHC Ion Beams 1667
  • F. Antoniou, G. Arduini, H. Bartosik, T. Bohl, S. Cettour Cave, K. Cornelis, D. Manglunki, Y. Papaphilippou
    CERN, Geneva, Switzerland
  An optics with low transition energy has been developed in the SPS for removing intensity limitations of the LHC proton beam and has become operational towards the second part of the 2012 LHC proton run. This optics was also used for filling the LHC with lead ions during the p/Pb run of the beginning of 2013. The impact of this optics in the performance of the LHC ion beam is studied here, especially with respect to collective effects, at the SPS injection energy. In particular, the potential gain of the increased beam sizes provided by this optics, with respect to losses and emittance blow up due to space-charge and Intrabeam Scattering (IBS) is evaluated. The measured lifetime is compared with the one provided by the Touschek effect and its interplay with RF noise is studied. The models are supported by measurements in the SPS and in the LHC flat bottom.  
WEPEA046 Experimental Observations from the LHC Dynamic Aperture Machine Development Study in 2012 2606
  • M. Giovannozzi, S. Cettour Cave, R. De Maria, M. Ludwig, A. Macpherson, S. Redaelli, F. Roncarolo, M. Solfaroli Camillocci, W. Venturini Delsolaro
    CERN, Geneva, Switzerland
  In view of improving the understanding of the behaviour of the dynamic aperture and to benchmark the numerical simulations performed so far, two experimental sessions have been scheduled at the LHC. The observations of the first sessions have been reported elsewhere[1], while in this paper the latest observations in terms of beam currents, blm losses and beam sizes will be described. The octupolar spool pieces have been used to artificially reduce the dynamic aperture and then induced slow beam losses. Alternating signs have been used in order to probe different configurations. Finally, scans over the strength of the decapolar spool pieces have been performed too.
[1] M. Giovannozzi et al., “First Experimental Observations from the LHC Dynamic Aperture Experiment”, in proceedings of IPAC12, p. 1362
WEPEA061 The First LHC p-Pb run: Performance of the Heavy Ion Production Complex 2648
  • D. Manglunki, M. E. Angoletta, H. Bartosik, G. Bellodi, A. Blas, M.A. Bodendorfer, T. Bohl, C. Carli, E. Carlier, S. Cettour Cave, K. Cornelis, H. Damerau, A. Findlay, S.S. Gilardoni, S. Hancock, J.M. Jowett, D. Kuchler, M. O'Neil, Y. Papaphilippou, S. Pasinelli, R. Scrivens, G. Tranquille, B. Vandorpe, U. Wehrle, J. Wenninger
    CERN, Geneva, Switzerland
  TThe first LHC proton-ion run took place in January-February 2013; it was the first extension to the collider programme, as this mode was not included in the design report. This paper presents the performance of the heavy ion and proton production complex, and details the issues encountered, in particular the creation of the same bunch pattern in both beams.  
THPEA040 Design of a Magnetic Bump Tail Scraping System for the CERN SPS 3228
  • Ö. Mete, J. Bauche, F. Cerutti, S. Cettour Cave, K. Cornelis, L.N. Drøsdal, F. Galleazzi, B. Goddard, L.K. Jensen, V. Kain, Y. Le Borgne, G. Le Godec, M. Meddahi, E. Veyrunes, H. Vincke, J. Wenninger
    CERN, Geneva, Switzerland
  • A. Mereghetti
    UMAN, Manchester, United Kingdom
  The LHC injectors are being upgraded to meet the demanding beam specification required for High Luminosity LHC (HL-LHC) operation. In order to reduce the beam losses which can trigger the sensitive LHC beam loss interlocks during the SPS-to-LHC beam injection process, it is important that the beam tails are properly scraped away in the SPS. The current SPS tail cleaning system relies on a moveable scraper blade, with the positioning of the scraper adjusted over time according to the orbit variations of the SPS. A new robust beam tail cleaning system has been designed which will use a fixed scraper block towards which the beam will be moved by a local magnetic orbit bump. The design proposal is presented, together with the related beam dynamics studies and results from machine studies with beam.