Beam test of a PIN-diode read out PWO calorimeter with electron energies from 5 to 40 GeV at CERN SPS

The large-area silicon photodiode PIN is one of the candidates for the lead tungstenate photon detector readout in the large heavy ion collision experiment ALICE. The PIN-diode was assembled with the lead tungstate crystal and a low-noise preamplifier into a complete detector unit. A beam test of a 5 $\times $ 5 detector unit matrix was carried out on the SPS accelerator at CERN. The energy resolution was measured with the electron beam energy ranging from 5 to 40 GeV. The summation correction method was implemented, and an excellent linearity of the signal peak value of the detector versus the nominal beam energy was obtained. In addition, a preliminary study of the punch-through effect in the high energy range was performed. A bulge of high-energy signals was identified at beam energies above 10 GeV, but only accounting for less than 1% of the accumulated statistics. Considering the mean energy of the excess is twice large than the regular signal, it was probably mainly due to the accumulation caused by two electrons hitting the detector at the same time, rather than the punch-through effect.