Study of some factors affecting the performance of microstrip gas chambers in an LHC environment

A study of neutron-induced interaction processes in MicroStrip Gas Counters is presented. The MicroStrip Gas Counter (MSGC) is a particle detector intended for use as part of the proposed ATLAS experiment at the LHC in CERN. An overview of ATLAS is presented and the principles of operation of the MSGC are described. Results from the operation of an MSG test chamber in the lab are presented. The results from an experiment to measure the signal produced in MSGCs by low energy neutrons at the ISIS synchrotron are presented and an account is given of a Monte Carlo model which simulates neutron-induced signals in MSGCs. The results from the model are compared with those from the neutron irradiation experiment at ISIS. The model is used to make predictions of the neutron-induced signal in MSGCs at ATLAS where a high background flux of low energy neutrons is expected. The model makes predictions of the spectrum and rate of neutron-induced counts and calculates the neutron-induced occupancy and charge loading of MSGCs in ATLAS. The model predicts that neutron interactions in the chamber will result in very large pulses being produced. The model predicts that these pulses could result in an increase in the occupancy of MSGCs of up to 7 [percent] and an increase in charge loading of up to 160 [percent].