Radiation dose simulation during laser-plasma proton acceleration experiments and method to increase the measurement resolution of the proton energy spectrum

Abstract

The paper discusses some 3D simulations to compute the ionizing radiation dose during laser-plasma experiments leading to the generation of accelerated protons and electrons. Also, we suggest a new method to increase the measurement resolution of the proton energy spectrum. Monte-Carlo simulations of the radiation doses map around the laser-foil interaction point are performed using Geant4 General Particle Source code and the particular geometry chosen for the experimental setup. We obtain the map of the radiation dose distribution for high-power laser - thin solid target experiments, considering a cubic geometry of the interaction chamber. The computed radiation dose distribution shows a good agreement with various, previously obtained experimental results, and could be a step towards simulating the radiation environment inside of a spacecraft. To characterize the laser-plasma accelerated protons, we introduce a new method to enhance the measurement resolution of the proton energy spectrum by employing a stack of thin solid detectors, preferably CR-39. Each detector is thinner than the Bragg peak region on the Bragg curve that characterizes the loss of kinetic energy as a function of the particle penetration depth in the detector material. The relevance of this method for space radiation characterization and cybersecurity insurance is highlighted.