Calibration of the ALICE Photon Spectromter (PHOS) using the neutral pion to gamma gamma decay

Abstract

The Large Hadron Collider (LHC) is under construction beneath the border between Switzerland and France. If it is successful, it will accelerate and collide protons at 7 T eV per proton in center of mass. Furthermore, it will collide lead (Pb) nuclei at 2.76 T eV per nucleon. ALICE is a LHC experiment dedicated to heavy ion physics. It will have two electro-magnetic calorimeters. One of these, the PHOton Spectrometer (PHOS), will provide high precision coverage at mid- rapidity in about 1/3 of the full azimuthal angle. We will go into the details of one of these techniques, calibration using neutral pions (π 0 ). Furthermore, we will present an implementation of this technique and the result of the implementation used on simulated data. Lastly, we will attempt to evaluate the techniques effectiveness.