Monte Carlo simulation of a liquid scintillation counter using geant4 code

Abstract

This paper presents a first approach to the use of the GEANT4 Monte Carlo (MC) technique in liquid scintil-lation counting (LSC) applied to measurements in radiological laboratories. The GEANT4 software was developed by RD44,a worldwide collaboration of national institutes, laboratories, and large high-energy physics experiments. GEANT4 is a pub-lic software package composed of tools that can be used to accurately simulate the passage of particles through matter. TheGEANT4 catalog of processes at optical wavelengths includes refraction and reflection at medium boundaries, bulk absorp-tion, and Rayleigh scattering. Processes that produce optical photons include the Cherenkov effect, transition radiation, andscintillation.The simulated setup includes a vial containing the scintillation cocktail in between 2 opposite photomultipliers tubes (PMTs)working in sum-coincidence mode. The decay of several beta emitters (such as 14C and 3H) can be simulated, as well as alphaor EC emitters. Additionally, significant information could be obtained, such as the energy deposited by decay into the scin-tillation cocktail or the light output generated into the scintillation cocktail. GEANT4 is a useful tool for efficiency calibra-tion, stopping power calculations, or wall effect studies for different scintillation cocktails and geometries.