Simulation of a high-energy electron beam transmission through titanium and Kapton\(^\circledR\) thin films

• Published in: arXiv.org 2021-12
• Main Authors: Malykhina, Tetiana, Karpus, Stepan, Shopen, Oleg, Prystupa, Valerii
• Format: Article
• Language: English
• Subjects: Bremsstrahlung; Computer simulation; Electron accelerators; Electron beams; Energy; Energy spectra; High energy electrons; Kapton (trademark); Metal foils; Polyimide resins; Scattering angle; Simulation; Thickness; Thin films; Titanium
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.2112.07487

The results of computer simulation of the high-energy electrons passage through thin layers of titanium (Ti) and polyimide Kapton\(^\circledR\) in the energy range from 3 to 20 MeV are presented. Simulation is carried out using the Geant4 toolkit. The thickness of the Ti foil in the model experiment is 50 microns, the thickness of the Kapton\(^\circledR\) film is 110 microns. The purpose of the calculations is to reveal the possibility of using the Kapton\(^\circledR\) film in the output devices of linear electron accelerators. It was necessary to calculate the probable values of the energy absorbed in a Kapton\(^\circledR\) film and in a Ti foil for each value of primary electrons energy. Another important characteristic is the divergence radius of the electron beam at a predetermined distance from the film, or the electron scattering angle. As a result of calculations, the energy spectra of bremsstrahlung gamma-quanta, formed during the passage of electrons through the materials of the films, are obtained. The most probable values of the energy absorbed in the Ti foil and in the Kapton\(^\circledR\) film are calculated. The scattering radii of an electron beam for the Kapton\(^\circledR\) film and also for the Ti foil at a distance of 20 cm are estimated. It is shown that the ratio of the total amount of bremsstrahlung gamma quanta in the case of use the Kapton\(^\circledR\) film is approximately 0.56 of the total amount of bremsstrahlung gamma quanta when using the Ti foil. The analysis of the calculated data showed that the use of Kapton\(^\circledR\) as a material for the manufacture of output devices for high-energy electron beams is more preferable in comparison to Ti films. The use of Kapton\(^\circledR\) instead of Ti makes it possible to significantly reduce the background of the generated bremsstrahlung gamma quanta and reduce the scattering radius of the electron beam.