Using Geant4 Monte Carlo toolkit to evaluate a low power X-ray tube generator configuration

G Hoff; E E Streck; A Lai; V Fanti; B Golosio; C D Nascimento; E G Souza

doi:10.1016/j.apradiso.2020.109487

Using Geant4 Monte Carlo toolkit to evaluate a low power X-ray tube generator configuration

Appl Radiat Isot. 2021 Feb:168:109487. doi: 10.1016/j.apradiso.2020.109487. Epub 2020 Oct 24.

Authors

G Hoff¹, E E Streck², A Lai³, V Fanti³, B Golosio³, C D Nascimento⁴, E G Souza⁴

Affiliations

¹ Physics Department, University of Cagliari, Monserrato, Italy; Department of Cagliary, National Institute of Nuclear Physics, Monserrato, Italy; Medical Physics and Radioprotection Service, Hospital de Clínicas de Porto Alegre, Porto Alegre, Brazil. Electronic address: ghoff.gesic@gmail.com.
² Physics College at Pontifical Catholic University of Rio Grande do Sul (retired professor), Porto Alegre, Brazil.
³ Physics Department, University of Cagliari, Monserrato, Italy; Department of Cagliary, National Institute of Nuclear Physics, Monserrato, Italy.
⁴ Graduate Program in Computer and Electronic Engineering at Catholic University of Pelotas, Pelotas, Brazil.

PMID: 33339703
DOI: 10.1016/j.apradiso.2020.109487

Abstract

Monte Carlo technique has been widely used as an important tool to develop new irradiation equipment, prototype medical equipment parts, and test methodologies for dosimetry. In this manuscript, we present a methodology to design a low power X-ray tube generator using the Geant4 Monte Carlo toolkit. The simulations were performed considering a large number of variables, namely, the material composition of the target track, the window thickness, and the air pressure of the X-ray tube. The X-ray production was simulated considering monoenergetic electron beams impinging on targets of tungsten and copper with incident kinetic energies ranging from 20 keV to 60 keV and initial divergences from 5° to 30°. For the polyenergetic emission, a conservative approach with Gaussian energy distribution was adopted. The analysis indicates that among the evaluated parameters, the incident kinetic energy, and the target material produced the most notable changes in the spectra shape and conversion efficiency (CE), significantly impacting the X-ray tube design. The studies provide a reliable methodology to explore general configurations for X-ray tube generators, defining the best geometry, material compositions, and thicknesses to be used on spectroscopy applications.

Keywords: Monte Carlo simulation; Transport models; X-ray generator design; X-ray sources.