Development and Benchmarking of Charged Particle Propagation Methods in G4-ASPP

Abstract

Abstract A new transport tool that simultaneously accounts for the impacts of external electromagnetic fields and bulk shielding material on charged particle dynamics, G4-ASPP, was developed to streamline active radiation shielding assessment and design for spacecraft. Transport simulations were performed to assess the accuracy and speed of G4-ASPP particle propagation methods in electromagnetic fields against standard methods. The time-step-based Velocity-Verlet propagation method and an analogous distance-stepping method used in G4-ASPP were derived. The symplecticity and phase-space conservation properties of each method are discussed. Results suggest the implementation of a 4th-order Runge-Kutta distance-stepping method into G4-ASPP to improve trajectory accuracy without sacrificing much speed.