Author/Authors :
Abbon، نويسنده , , P. and Albrecht، نويسنده , , E. and Alexakhin، نويسنده , , Yu.A. Alexandrov، نويسنده , , Yu. and Alexeev، نويسنده , , G.D. and Alekseev، نويسنده , , M.G. and Amoroso، نويسنده , , A. and Angerer، نويسنده , , H. and Anosov، نويسنده , , V.A. and Bade?ek، نويسنده , , B. and Balestra، نويسنده , , F. and Ball، نويسنده , , J. and Barth، نويسنده , , J. and Baum، نويسنده , , G. and Becker، نويسنده , , M. and Bedfer، نويسنده , , Y، نويسنده ,
Abstract :
The COMPASS experiment makes use of the CERN SPS high-intensity muon and hadron beams for the investigation of the nucleon spin structure and the spectroscopy of hadrons. One or more outgoing particles are detected in coincidence with the incoming muon or hadron. A large polarised target inside a superconducting solenoid is used for the measurements with the muon beam. Outgoing particles are detected by a two-stage, large angle and large momentum range spectrometer. The setup is built using several types of tracking detectors, according to the expected incident rate, required space resolution and the solid angle to be covered. Particle identification is achieved using a RICH counter and both hadron and electromagnetic calorimeters. The setup has been successfully operated from 2002 onwards using a muon beam. Data with a hadron beam were also collected in 2004. This article describes the main features and performances of the spectrometer in 2004; a short summary of the 2006 upgrade is also given.
Keywords :
Scintillating fibre detector , Micromegas detector , GEM detector , Drift chamber , Straw tube detector , RICH detector , Calorimetry , DAQ , Front-end electronics , Fixed-target experiment , Hadron structure , Polarised DIS , Polarised target , Silicon microstrip detector , MWPC
