Author: Puzo, P.M.
Paper Title Page
TUPC141 LHC Beam Loss Pattern Recognition 1353
 
  • A. Marsili, E.B. Holzer, P.M. Puzo
    CERN, Geneva, Switzerland
 
  One of the systems protecting CERN's Large Hadron Collider (LHC) is the Beam Loss Monitoring system (BLM). More than 3600 monitors are installed around the ring. The beam losses are permanently integrated over 12 different time intervals (from 40 microseconds to 84 seconds). When any loss exceeds the thresholds defined for the integration window, the beam is removed from the machine. Understanding the origin of a beam loss is crucial for machine operation, as it can help to avoid a repeat of the same scenario. The signals read from given monitors can be considered as entries of a vector. This article presents how a loss map of unknown cause can be decomposed using vector based analysis derived from well-known loss scenarios. The algorithms achieving this decomposition are described, as well as the accuracy of the results.  
 
TUPZ002 90 m β* Optics for ATLAS/ALFA 1798
 
  • S. Cavalier, P.M. Puzo
    LAL, Orsay, France
  • H. Burkhardt
    CERN, Geneva, Switzerland
  • A. Peskov
    NNGU, Nizhny Novgorod, Russia
 
  We describe a high β* optics developed for the ATLAS detector at the LHC interaction regions (IR1), Roman Pots have been installed 240 m left and right of IR1 to allow to measure the absolute luminosity and the total elastic cross section for ATLAS with ALFA (Absolute Luminosity for ATLAS). Ultimately, it is planned to preform these measurements at a very high β* of 2625 m. Here we describe a new, intermediate β* = 90 m optics, which has been optimized for compatibility with the present LHC running conditions. We described the main features and expected performance of this optics for ALFA.