Analysis of dose-let distribution in the human body irradiated by high energy hadrons

Sato, Tatsuhiko   ; Tsuda, Shuichi  ; Sakamoto, Yukio; Yamaguchi, Yasuhiro; Niita, Koji*

For the purposes of radiological protection, it is extremely important to analyse profiles of energy deposition in the human body irradiated by high energy hadrons. We therefore performed Monte Carlo calculations of dose distributions in terms of the LET of ionising particles using a newly developed particle transport code PHITS for incidences of neutrons, protons and pions with energies from 100 MeV to 200 GeV. Based on our calculations, we found that more than 80% and more than 90% of the total deposited energies are imparted by particles with a LET below 10 keV/mm for the irradiations of neutrons and the charged particles, respectively. These results are expected to be useful in micro-dosimetric analysis for elucidating the dependence of the biological effects of irradiation on the incident radiation type and energy.