Possibilities of fast hadron and electron dicrimination in electromagnetic sampling calorimeter

The possibilities of fast hadron rejection using minimal information about the longitudinal shower structure were analysed. Together with the total energy deposition, the energy deposited in the part of the shower Λxo thick located at a distance of xo from the calorimeter face was used. The value of the rejection R is shown to depend essentially on Λxo and xo and quite large possibilities exist for the effective rejections of a hadron with momentum >5GeV/c on the level of R<2x10-3 for the well known particle momentum, and R<0,1+0,2 for unknown one. In the second case it is establiched that the rejection factor decreases with the calorimeter length, and quantitative estimates at different energies are given. 14 refs