Results of a beam test of the combined lead glass and PWO cells detector for the COMPASS electromagnetic calorimeter

Results of a beam test of the combined PWO ( 20×20×200 mm³ in size) and lead glass ( 38×38×450 mm³ in size) cells for a COMPASS electromagnetic calorimeter prototype are described. The dependence of total energy deposited in a combined calorimeter as a function of distance L between front faces of lead glasses and PWO cells has been measured for electrons of different energies. An optimal value for L is obtained. The energy resolution is measured for the combined calorimeter. The position accuracy is estimated. The comparison of the measured characteristics of the calorimeter prototype with Monte Carlo simulation results is shown.