Author/Authors :
Alexeev، نويسنده , , M. and Birsa، نويسنده , , R. and Bradamante، نويسنده , , F. and Bressan، نويسنده , , A. and Dalla Torre، نويسنده , , S. and Duic، نويسنده , , V. Di Giorgi، نويسنده , , M. and Gobbo، نويسنده , , B. and Levorato، نويسنده , , S. and Martin، نويسنده , , A. and Sbrizzai، نويسنده , , G. and Schiavon، نويسنده , , P. and Sozzi، نويسنده , , F. and Tessarotto، نويسنده , , F.، نويسنده ,
Abstract :
We present an indirect measurement of possible long term variations of the CsI quantum efficiency in solid state photocathodes in MWPC. This type of photon detectors has been used since 2001 in the Cherenkov Imaging detector RICH-1 of the COMPASS experiment at CERN SPS. Data from six years of COMPASS data taking are used to evaluate the mean number of detected photons per particle. The results do not indicate any severe CsI quantum efficiency ageing effect.
Keywords :
rich , MWPC , CsI quantum efficiency , UV photons , COMPASS
