• T. Aumeyr, G.A. Blair, S.T. Boogert, G.E. Boorman, A. Bosco
  JAI, Egham, Surrey
• K. Balewski, E. Elsen, V. Gharibyan, G. Kube, S. Schreiber, K. Wittenburg
  DESY, Hamburg

The PETRA-III Laser-wire, a Compton scattering beam size measurement system at DESY, uses an automated mirror to scan a Q-switched laser across the electron beam and is developed from the system previously operated at PETRA-II. This paper reports on recent upgrades of the optics, vacuum vessel and data acquisition. First beam profile measurements are also presented.

• M. Micheler, G.A. Blair, G.E. Boorman, V. Karataev, K. Lekomtsev
  JAI, Egham, Surrey
• R. Corsini, A.E. Dabrowski, T. Lefèvre
  CERN, Geneva
• S. Molloy
  Royal Holloway, University of London, Surrey

A setup for the investigation of Coherent Diffraction Radiation (CDR) from a conducting screen as a tool for non-invasive longitudinal electron beam profile diagnostics has been designed and installed in the Combiner Ring Measurement (CRM) line of the CLIC Test Facility (CTF3, CERN). In this report the status of the monitor development and results on the interferometric measurements of CDR spectra are presented. The CDR signal correlation with an RF pickup and a streak camera is reported. The future plans for the system improvements are also discussed.

• H. Burkhardt
  CERN, Geneva
• G.A. Blair, L.C. Deacon
  Royal Holloway, University of London, Surrey

We report on a study of muon backgrounds in CLIC. For this we combined halo and tail generation using HTGEN with detailed tracking by BDSIM of impacting halo particles and resulting secondaries from the collimation spoilers to the detector.