Speakers
Description
The accurate modeling of charged-particle transport and energy loss, or stopping power, in hot, dense matter is a foundational challenge in high-energy-density physics and aneutronic nuclear fusion research, particularly for the proton-boron (p-$^{11}$B) reaction. Standard Monte Carlo simulation tools, such as Geant4, are optimized for cold-matter interactions and fail to account for the collective plasma effects critical to the self-heating and energy balance of a fusion fuel.
To address this gap, a customized physics framework was developed and implemented within the Geant4 toolkit. This framework involved creating a novel physics class to override the default energy loss calculations for energetic alpha particles. The custom implementation incorporates advanced theoretical models, specifically the Modified Li-Petrasso (MLP) and Novel Single Scattering Model (NSSM), which account for the plasma's temperature and density. Plasma order parameters were first calculated and confirmed that the p-$^{11}$B target operates within the ideal, non-degenerate, and linear response regime, thereby justifying the analytical models used.
The primary finding is the successful numerical validation of the custom Geant4 implementation. Comparative analysis demonstrates that the simulation accurately tracks alpha particle stopping power across the relevant parametric range, showing strong agreement with established analytical benchmarks. This work successfully moves the simulation of p-$^{11}$B alpha particle transport from theoretical concept to a validated, implementable transport code, providing a necessary predictive tool for modeling thermalization, energy deposition profiles, and burn-up fraction in next-generation aneutronic fusion devices.