Benchmark study for energy deposition by energetic electrons in thick elemental slabs: Monte Carlo results and experiments

The energy deposition profiles when electrons with 0.5 MeV to 2 MeV kinetic energies impinge on a slab of elemental targets are presented in this paper. The target materials studied were single elements with atomic numbers between 6 and 73, thus covering representative low to high Z materials. The energy deposition profiles were computed using TIGER, the 1-D module of the Integrated Tiger Series (ITS) version 3.0, and MCNP4C. The targets were divided into the scoring subzones of 0.025r₀ thickness in all Monte Carlo simulations, where r₀ is the continuous slowing down approximation (CSDA) range of the incident electrons. Then, the computed profiles were compared to available experimental values. The comparison showed that the MCNP4C results followed the experimental data more closely than TIGER, especially in the broad peak regions. In general, however, the agreement of the energy deposition profiles computed by either code with the measured data was acceptable within the combined uncertainties of experiments and calculations. The observed discrepancies between the MCNP and TIGER results were due to different energy-indexing algorithms employed in the two codes. However, it was also found that the MCNP results were dependent on the user selection of the scoring subzone thickness, thus the MCNP simulations are subjected to some arbitrariness.