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arXiv · 2112.07440

Geant4 modeling of the bremsstrahlung converter optimal thickness for studying the radiation damage processes in organic dyes solutions

Abstract

This work is dedicated to computer modeling of the parameters of a tungsten converter for studying the processes of radiation damage during the interaction of ionizing radiation with solutions of organic dyes. Simulation was carried out in order to determine the optimal thickness of the converter under predetermined experimental conditions. Experimental conditions include: energies and type of primary particles, radiation intensity, target dimensions, relative position of the radiation source and target. Experimental studies of the processes of radiation damage occurring in solutions of organic dyes are planned to be carried out using the linear electron. The tungsten converter is used to generate a flux of bremsstrahlung gamma rays. One modeling problem is determination of the converter thickness at which the flux of bremsstrahlung gamma will be maximal in front of the target. At the same time, the flow of electrons and positrons in front of the target should be as low as possible. Another important task of the work is to identify the possibility of determining the relative amount of radiation damage in the target material by the Geant4 modeling method. Computational experiments were carried out for various values of the converter thickness - from 0 mm (converter is absent) to 8 mm with a step of 1 mm. The developed program operates in a multithreaded mode. The G4EmStandardPhysics_option3 model of the PhysicsList was used in the calculations. A detailed analysis of the obtained data has been performed. As a result of the data analysis, the optimal value of the tungsten converter thickness was obtained.

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Tetiana Malykhina, Vladimir Kovtun, Valentin Kasilov, Sergey Gokov. 2021-12-14. Geant4 modeling of the bremsstrahlung converter optimal thickness for studying the radiation damage processes in organic dyes solutions. https://doi.org/10.26565/2312-4334-2021-4-10

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