Performance study of the FoCal detector sensors using cluster size data

Abstract

The FoCal is a proposed upgrade for the ALICE detector. The FoCal is an electromagnetic sampling calorimeter which uses digital pixel counting to measure the energy of the incoming particle. An important aspect of the detector response is the cluster size. In this thesis the goal was to examine if there is any external factor that can influence the cluster size. Factors investigated in this study are the incoming angle of the cosmic muons and the position of the cluster on the sensor. A simulation is performed to compare with the data and to see if the charge sharing model gives a realistic view of the observations. In the measured data no dependence between the cluster size and angle was found. Only when the angles in the simulation were larger than could be measured there was a dependence found. For the positional dependence the difference in the cluster size between the different channels was measured. Here there was no significant difference found.