Features of Particle and Heavy Ion Transport code System (PHITS) version 3.02

TLDR

The paper summarizes the basic features of PHITS3.02, focusing on the physics models and new functions added since PHITS2.52. PHITS3.02 implements condense‑history and track‑structure methods for electron and positron transport, introduces new tallies, a radioisotope source‑generation function, and software tools for medical physics applications. The upgrade improves accuracy, extends applicable energy ranges, and has attracted over 3,000 users in accelerator design, radiation shielding, medical physics, and cosmic‑ray research.

Abstract

We have upgraded many features of the Particle and Heavy Ion Transport code System (PHITS) and released the new version as PHITS3.02. The accuracy and the applicable energy ranges of the code were greatly improved and extended, respectively, owing to the revisions to the nuclear reaction models and the incorporation of new atomic interaction models. Both condense history and track-structure methods were implemented to handle the electron and positron transport, although the latter is reliable only for simulations in liquid water. In addition, several user-supportive functions were developed, such as new tallies to efficiently obtain statistically better results, radioisotope source-generation function, and software tools useful for applying PHITS to medical physics. Owing to the continuous improvement and promotion of the code, the number of registered users has exceeded 3,000, and it is being used in diverse areas of study, including accelerator design, radiation shielding and protection, medical physics, and cosmic-ray research. In this paper, we summarize the basic features of PHITS3.02, especially those of the physics models and the functions implemented after the release of PHITS2.52 in 2013.