Alignment of the FoCal prototype detector with cosmic muons

Abstract

The Forward Calorimeter (FoCal) is a proposed subdetector upgrade for the ALICE experiment at CERN. In this research we refer to the FoCal prototype, which is a digital sampling electromagnetic calorimeter. In order to properly evaluate the energy resolution of the FoCal prototype the chip positions of the silicon chip sensors have to be well defined with respect to a fixed reference system. An algorithm that takes into account the strong correlation between sensor position and reconstructed track position is put in place. After the first iteration the chip positions are known to within an accuracy of 0.1 mm.