Recent developments and benchmarking of the PHITS code

最近のPHITSの開発動向及びそのベンチーマーク結果

Sihver, L.*; Mancusi, D.*; 佐藤 達彦   ; 仁井田 浩二*; 岩瀬 宏*; 岩元 洋介   ; 松田 規宏  ; 中島 宏; 坂本 幸夫

Sihver, L.*; Mancusi, D.*; Sato, Tatsuhiko; Niita, Koji*; Iwase, Hiroshi*; Iwamoto, Yosuke; Matsuda, Norihiro; Nakashima, Hiroshi; Sakamoto, Yukio

PHITSは、NMTC及びMCNPモデルを用いて核子・中間子輸送過程を、JAM, JQMD及びGEMモデルを用いて核反応過程を模擬できる汎用粒子輸送計算コードである。近年行ったベンチマーク試験の結果、PHITSは、電荷変換核反応断面積をやや過小評価することが判明した。本発表では、そのベンチマーク試験結果について述べるとともに、PHITSの精度向上のために行った核反応モデルの改良について詳しく説明する。

The General-Purpose Particle and Heavy-Ion Transport code System (PHITS) is based on NMTC and MCNP for nucleon/meson and neutron transport respectively; it includes the JAM hadron cascade model for high energy particle-induced reactions and JQMD for nucleus-nucleus collisions; the evaporation and/or fission stage of the reactions is handled by the GEM code. The experimental partial fragmentation cross sections appear to be systematically underestimated by a factor which is independent on the fragment species within the same data set. However, the simulated neutron energy spectra show generally a good agreement with measurements, and so do the attenuation and Bragg curves. These observations stimulate further benchmarking and give directions on possible improvements to be applied to the code in the near future.