ACORDE,a cosmic ray detector in ALICE.Firsts simulation studies

摘要

ACORDE (A COsmic Ray DEtector in ALICE) will be part of the ALICE detector at LHC and its objective is to provide a cosmic ray trigger (level 0).ACORDE will consist of an array of plastic scintillators placed on the top sides of the ALICE magnet.We describe the measurements that can be done with these counters in conjunction with some other components of ALICE and we give the first results of the performances of ACORDE.A simulation program,which includes the environment of ALICE and the rock above it,has been developed within the AliRoot framework to study atmospheric muons and multimuon events.The momentum spectrum and angular distribution of muons at the ground surface and at the top side of the ALICE magnet are shown.Preliminary results on the momentum resolution of muons detected by the TPC encourage the proposed Measurements.