GEANT4-DNA simulation of temperature-dependent and pH-dependent yields of chemical radiolytic species.

]. To validate our modifications, two sets of simulations were performed. A) A water cube with 1.0 km sides and a pH of 7 was irradiated with an isotropic electron source of 1 MeV. The end time was 1 µs. The temperatures varied from 25 °C to 150 °C. B) Same setup as A) was used, however, the temperature was set to 25 °C while the pH varied from 5 to 9. The results were compared with published experimental and simulated work.
Main results: The IRT method in GEANT4-DNA was successfully modified to simulate G-values for radiolytic species at different temperatures and pH values. Our temperature-dependent results agreed with experimental data within 0.64% to 9.79%, and with simulated data within 3.52% to 12.47%. The pH-dependent results agreed well with experimental data within 0.52% to 3.19% except at pH of 5 (15.99%) and with simulated data within 4.40% to 5.53%. The uncertainties were below ± 0.20%. Overall our results agreed better with experimental than simulation data.
Significance: Modifications in GEANT4-DNA code enabled calculation of G-values for radiolytic species at different temperature and pH values.