• B. Goddard, I.V. Agapov, E. Carlier, L. Ducimetière, E. Gallet, M. Gyr, L.K. Jensen, O.R. Jones, V. Kain, T. Kramer, M. Lamont, M. Meddahi, V. Mertens, T. Risselada, J.A. Uythoven, J. Wenninger, W.J.M. Weterings
  CERN, Geneva

Initial commissioning of the LHC beam dump system with beam took place in August and September 2008. The preparation, setting-up and the tests performed are described together with results of the extractions of beam into the dump lines. Analysis of the first detailed aperture measurements of extraction channels and kicker performance derived from dilution sweep shapes are presented. The performance of the other equipment subsystems is summarised, in particular that of the dedicated dump system beam instrumentation.

• M. Meddahi, I.V. Agapov, K. Fuchsberger, B. Goddard, W. Herr, V. Kain, V. Mertens, D.P. Missiaen, T. Risselada, J.A. Uythoven, J. Wenninger
  CERN, Geneva
• E. Gianfelice-Wendt
  Fermilab, Batavia

Funding: Work partly supported by Fermilab, operated by Fermi Research Alliance, LLC under Contract No. DE-AC02-07CH11359 with the United States Department of Energy

Through May to September 2008, further beam commissioning of the SPS to LHC transfer lines was performed. For the first time, optics and dispersion measurements were also taken in the last part of the lines, and into the LHC. Extensive trajectory and optics studies were conducted, in parallel with hardware checks. In particular dispersion measurements and their comparison with the beam line model were analysed in detail and led to propose the addition of a “dispersion-free” steering algorithm in the existing trajectory correction program.