Improvement of photonuclear reaction model below 140 MeV in the PHITS code

Noda, Shusaku; Hashimoto, Shintaro  ; Sato, Tatsuhiko   ; Fukahori, Tokio  ; Chiba, Satoshi*; Niita, Koji*

The author improved the photonuclear reaction model in the PHITS code for incident photon energy below 140 MeV. There are three major improvements: (1) JENDL Photonuclear Data File (JENDL/PD-2004) is adopted to determine the total reaction cross section, (2) the evaporation model for the giant resonance of some light nuclei is modified considering the isospin selection rule, and (3) the quasideuteron disintegration process is implemented in the JAERI Quantum Molecular Dynamics model. The improved PHITS code can contribute to various practical applications such as neutron dose estimation in X-ray therapy.