Calculation of the exposure buildup factors for x-ray photons with continuous energy spectrum using Monte Carlo code

Abstract

The exposure buildup factors are very important for the calculation of radiation shielding and also applied radiation. We must distinguish the monoenergetic and continuous energy spectrum gamma source in order to calculate the exposure buildup factors. In this study, the exposure buildup factors for two X-ray continuous energy spectrum (bremsstrahlung) with 5 and 10 MeV endpoint energy were calculated up to depths 10 mfp of water. It was observed that there is a large difference between the obtained exposure buildup factors due to the monoenergetic and continuous energy spectrum gamma source. The calculation results show that the relative differences in 5 MeV energy for 1 mfp to 10 mfp are 114% to 44%, respectively, and also the relative differences in 10 MeV energy for 1 mfp to 10 mfp are 87% to 38%, respectively. Actually, the main purpose of this paper is to illustrate the fact that there is a significant difference between the exposure buildup factor due to the continuous and monoenergetic gamma source. Therefore, radiation staffs must pay more attention to calculate the thickness of the radiation shields for continuous energy gamma source.

Feasibility of using heavy water in order to design of a photoneutron source based on 5 MeV electron linear accelerator

“…Bremsstrahlung radiation has been used as a photon source, and these photons interact with heavy water. In our previous work, from the point of radiation protection we investigated the buildup factors for the emitted bremsstrahlung photons from the tungsten in order to find the correct thickness of the shield [50]. The heavy water is used as photoneutron target for two reasons.…”

A Closer Look on Nuclear Radiation Shielding Properties of Eu3+ Doped Heavy Metal Oxide Glasses: Impact of Al2O3/PbO Substitution

“…This value indicates the thickness of a shielding material at which the intensity of a gamma-ray incident on it is effectively halved. Additionally, critical gamma-ray shielding properties such as mean free path (λ) [28] and effective atomic numbers (Z eff ) [29] were evaluated in relation to gamma-ray attenuation, exposure, and energy absorption build-up factors (EBF and EABF) [30][31][32][33]. On the other hand, we sought to assess the attenuation characteristics of SM glasses against fast neutrons, which may be advantageous for specific applications in neutron-based (i.e., photodisintegration) radiation facilities.…”

Fast Neutron and Gamma-Ray Attenuation Properties of Some HMO Tellurite-Tungstate-Antimonate Glasses: Impact of Sm3+ Ions

“…This quantity provides remarkable information about the thickness of a shielding material at which the intensity of a gamma ray received on it is effectively halved. Additionally, key gamma ray shielding characteristics, such as mean free path (λ) [14], effective atomic numbers (Z eff ) [15] against gamma-ray attenuation, exposure, and energy absorption build-up factors (EBF and EABF) [16][17][18][19][20], were measured throughout the gamma-radiation energy range of 0.015-15 MeV. On the other side, we aimed to evaluate the SM glasses' attenuation properties against fast neutrons, which can be beneficial for special utilizations in neutron used/expected (i.e., photodisintegration) radiation facilities.…”