Silicon Detector Measurements of Energy Deposition in Aluminum by Monoenergetic Electrons

The energy depos ited at various depths in aluminum by incident monoenergetic electrons has been measured with a silicon-semiconductor, transmission detector. Beams of monoenergetic electrons with incident energies of 0.50, 0.75, and 1.0 MeV were directed normally on a semi-infinite slab of aluminum in which a 0.196-mm silicon detector was positioned at various depths. The pulse-height distributions recorded with the detector were converted to absorbed-energy distributions from which the probability of energy absorption per incident electron in the specific layer, as well as the absorbed energy as a function of depth in the material, could be determined. The curves of absorbed energy as a function of depth obtained for aluminum at each energy were compared to those calculated by Berger and Seltzer, employing a Monte Carlo method. Good agreement is shown between calculations and measurements.