Simulation of the Kinetic Energy Spectrum of Primary Electron Generated by a 6 keV X-Ray Source in a Gas Volume

TL;DR

This study simulates the kinetic energy spectrum of primary electrons generated by 6 keV X-ray interactions in various gas mixtures, highlighting the dominance of photoelectric effects and spectrum linearity.

Contribution

It provides a partial simulation of primary electron energy spectra for different gases and mixtures, emphasizing the linear combination property of the spectra.

Findings

Spectrum peaks correspond to inner shell ionization energies.

Compton effect is negligible at this energy range.

Energy spectrum of mixtures is a linear combination of individual spectra.

Abstract

With the intention of creating a complete simulation of the Thick GEM detector, this work presents a partial simulation of the interaction of 6 keV X-Ray radiation with a gas volume. For the gas, it was used pure Argon, Xenon and CO2 as well as a mixture of each noble gas with CO2 in a 70\%-30\% proportion. For this range of energy, the dominant physical effect is the photoelectric, therefore knowing the binding energies of the atoms we predict the kinetic energy of the primary electron. A simulated energy spectrum of the primary electron kinetic energy was obtained, which contains peaks corresponding to the inner shell's ionization of the atoms. The spectrum shows very little Compton effect, transferring only small energies (in the order of eVs). We concluded that energy spectrum for the mixture is a linear combination of the spectrum of its individual components.