• A.I. Drozhdin, N.V. Mokhov, S.I. Striganov
  Fermilab, Batavia

Funding: Work supported by Fermi Research Alliance, LLC, under contract No. DE-AC02-07CH11359 with the U.S. Department of Energy.

With a fully-operational high-efficient collimation system in the LHC, nuclear interactions of circulating protons with residual gas in the machine beam pipe can be a major sources of beam losses in the vicinity of the collider detectors, responsible for the machine-induced backgrounds. Realistic modeling of elastic and inelastic interactions of 7-TeV protons with nuclei in the vacuum chamber of the cold and warm sections of the LHC ring - with an appropriate pressure profile - is performed with the STRUCT and MARS15 codes. Multi-turn tracking of the primary beams, propagation of secondaries through the lattice, their interception by the tertiary collimators TCT as well as properties of corresponding particle distributions at the CMS and ATLAS detectors are studied in great detail and results presented in this paper.

• K.T. McDonald
  PU, Princeton, New Jersey
• J.R.J. Bennett
  STFC/RAL/ASTeC, Chilton, Didcot, Oxon
• O. Caretta, P. Loveridge
  STFC/RAL, Chilton, Didcot, Oxon
• A.J. Carroll, V.B. Graves, P.T. Spampinato
  ORNL, Oak Ridge, Tennessee
• I. Efthymiopoulos, A. Fabich, F. Haug, J. Lettry, M. Palm, H. Pereira
  CERN, Geneva
• H.G. Kirk, H. Park, T. Tsang
  BNL, Upton, Long Island, New York
• N.V. Mokhov, S.I. Striganov
  Fermilab, Batavia

The MERIT (MERcury Intense Target) experiment was run in the fall of 2007 using 14 and 24 GeV intense proton beams from the CERN PS. It is a proof-of-principle experiment designed to validate a target concept for producing an intense muon source for a future muon collider or neutrino factory. The experiment successfully demonstrated a target technique for multi-MW proton beams that utilizes a free-flowing liquid metal jet within the confines of a high-field solenoid. We describe the experimental strategy and parameters, as well as the results obtained and their implications for future muon-based accelerator facilities.

Slides

• I. Efthymiopoulos, A. Fabich, A. Grudiev, F. Haug, J. Lettry, M. Palm, H. Pereira, H. Pernegger, R.R. Steerenberg
  CERN, Geneva
• J.R.J. Bennett
  STFC/RAL/ASTeC, Chilton, Didcot, Oxon
• O. Caretta, P. Loveridge
  STFC/RAL, Chilton, Didcot, Oxon
• A.J. Carroll, V.B. Graves, P.T. Spampinato
  ORNL, Oak Ridge, Tennessee
• H.G. Kirk, H. Park, T. Tsang
  BNL, Upton, Long Island, New York
• K.T. McDonald
  PU, Princeton, New Jersey
• N.V. Mokhov, S.I. Striganov
  Fermilab, Batavia

The MERIT experiment is a proof-of-principle test of a target system for high power proton beam to be used as front-end for a neutrino factory complex or a muon collider. The experiment took data in autumn 2007 with the fast extracted beam from the CERN Proton Synchrotron (PS) to a maximum intensity of about 30·10¹² protons per pulse. We report results from the portion of the MERIT experiment in which separated beam pulses were delivered to a free mercury jet target with time intervals between pulses varying from 2 to 700 microseconds. The analysis is based on the responses of particle detectors placed along side and downstream of the target.

• H.G. Kirk, H. Park, T. Tsang
  BNL, Upton, Long Island, New York
• J.R.J. Bennett
  STFC/RAL/ASTeC, Chilton, Didcot, Oxon
• O. Caretta, P. Loveridge
  STFC/RAL, Chilton, Didcot, Oxon
• A.J. Carroll, V.B. Graves, P.T. Spampinato
  ORNL, Oak Ridge, Tennessee
• I. Efthymiopoulos, A. Fabich, F. Haug, J. Lettry, M. Palm
  CERN, Geneva
• K.T. McDonald
  PU, Princeton, New Jersey
• N.V. Mokhov, S.I. Striganov
  Fermilab, Batavia

We report on the analysis of data collected from the optical diagnostics of the MERIT experiment which was run at CERN in the fall of 2007. The breakup of the free mercury jet resulting from the impact of intense proton beams from the CERN PS within a magnetic field environment is described.