Accurate determination of cellular S-values for monoenergetic electron sources and beta emitting radionuclides using Geant4-DNA Monte Carlo code

In this paper, cellular S-values for monoenergetic electron sources with energy from 1 to 70keV and the Auger-electron emitting radionuclides Tc-99m and In-111 were calculated in liquid water using the Geant4 Monte Carlo toolkit with the low energy extension Geant4-DNA. The results were compared to corresponding MIRD database and the differences were calculated. Differences between Geant4-DNA and MIRD results up to 70% were found; However, for the present monoenergetic sources and radionuclides, they mostly remain below 20%. Calculated S-values in this paper, were in good agreement to S-values obtained in the other literatures. This study is an important step for performing cellular dosimetry which the results would improve the treatment planning in the country.