Measurement of absorbed dose distributions in a plastic phantom irradiated by 40- and 65-MeV quasi-monoenergetic neutrons

In order to validate dose evaluation methods for radiation shielding design of accelerator facilities, absorbed dose distributions in a plastic phantom of 30×30×30 cm3 slab were measured for 40- and 65-MeV quasi-monoenergetic neutrons with a tissue-equivalent proportional counter and a tissue-equivalent ionization chamber. The measured distributions were compared with the calculated ones from the energy deposition of charged particles and neutron energy spectra by using the Monte Carlo codes, HETC-3STEP and MORSE-CG/KFA, respectively. As a result, it was revealed that the calculation method used in the present work was applicable to absorbed dose evaluation for intermediate energy neutrons with high accuracy.