Features and applications of the analytical model for estimating terrestrial cosmic-ray fluxes; PARMA/EXPACS

Sato, Tatsuhiko   

Evaluation of the temporal and locational variations of cosmic ray fluxes generated through extensive airshower is very important for estimating cosmogenic nuclide yields, radiation doses for aircrews, and soft-error rates of semi-conductor devices. We therefore performed the EAS simulation using the Particle and Heavy Ion Transport code System PHITS. By fitting the results of the EAS simulation, we developed an analytical model for instantaneously estimating the cosmic-ray fluxes nearly anytime and anywhere in the Earth's atmosphere. The model is named PARMA/EXPACS, and used for various applications such as the estimation of cosmogenic nuclide production rates, and the analysis of footprint characteristics for soil moisture monitoring with cosmic-ray neutrons. The detail features and applications of PARMA/EXPACS will be presented at the meeting.