Study of response uniformity of the LHCb ECAL

Response uniformity of the LHCb electromagnetic calorimeter modules was studied at the beam of high energy muons. Tests of prototype module built with thin (0.5 mm) absorber and scintillator plates were also performed. In addition response variation of the inner ECAL module to 50 GeV electrons was measured. In order to verify our understanding of light collection uniformity a dedicated ray-tracer program for light propagation in different scintillator tiles was developed. Parameters of this program were tuned and checked using experimental data.