Correction method for the energy spectrum of laser-accelerated protons measured by CR-39 track detectors with stepwise energy filters

Abstract

A combination of CR-39 track detectors and a stepwise energy filter is a simple method to measure the energy spectrum of laser-accelerated protons. The number of etch pits in each area of the CR-39 detector is expected to represent the energy spectrum because the different thicknesses of the filters result in different areas into which the energy reaches in CR-39. However, the higher energy regions may overlap depending on the sensitivity of CR-39. To avoid overlapping, i.e., overestimation of the number of etch pits for each energy region, a correction method for the energy spectrum from the number of etch pits was developed. Based on the calculation results of the reaching energy values and incident energy ranges for CR-39, etch pits are selected that should be counted in each area. CR-39 with stepwise energy filters provides a corrected energy spectrum of laser-accelerated protons by applying the developed method.