The performance of the CMS ECAL Preshower detector at LHC
Presented by Zong-Kai LIU
Track: 01 - Early Experience and Results from LHC
The Preshower detector is part of the CMS endcap electromagnetic calorimeter, located in front of the lead tungstate crystals. It is composed of two lead absorbers and two orthogonal planes of silicon strip sensors. The purpose of the Preshower is to identify two closely spaced photons from pi0 decays, which allow an additional rejection of background for Higgs to two photon decay channel. A brief overview of the design of the Preshower, the response to beam commissioning, first in-situ absolute calibration, occupancy and the performance of Preshower-crystal cluster matching will be presented.