The response of an aluminum-scintillator calorimeter to electrons near the critical energy from 50 to 150 MeV and comparisons with the EGS4 program predictions
We measured electron shower transport through a finely granulated calorimeter composed of alternating layers of aluminum and plastic scintillator for electron energies of 53, 108 and 144 MeV. These data were in the transition region near to the critical energies for both aluminum and carbon. Previous measurements in this region suggested deviations from the predicted calorimeter energy resolution; however, our data were in agreement with resolutions calculated using the EGS4 computer program. We made detailed measurements of the penetration depth of electrons and their electromagnetic showers into the calorimeter, as well as the size of gaps where the energy was transported by neutral particles. These measurements were also found to be in general agreement with the EGS4 predictions. However, there was one significant discrepancy, the data showed significantly deeper shower penetration into the calorimeter than predicted by the program.