Estimation of Yields of OH Radicals in Water Irradiated by Ionizing Radiation

• DOI: 10.1269/jrr.46.333
• Publication Date: 2005-10-06T05:55:58Z
• Authors: Hiroshi YAMAGUCHI; Yukio UCHIHORI; Nakahiro YASUDA; Masashi TAKADA; Hisashi KITAMURA
• Keywords: 0301 basic medicine; Kinetics; 03 medical and health sciences; 0302 clinical medicine; Models, Chemical; Hydroxyl Radical; Radiation, Ionizing; Water; Computer Simulation; Dose-Response Relationship, Radiation; Linear Energy Transfer; Radiation Dosage; 7. Clean energy

The yield of OH radical induced by ionizing radiation was estimated by an empirical model; a prescribed diffusion model for a spur of single size applying to neutral water. Two representative spur distances were introduced, one for an incident primary charged particle and one for a representative secondary electron, to calculate chemical yields among active species in a spur. The total yield from the track was a combination of these primary and secondary yields. Two coefficients of this combination were the parameters of the present model. Based on an optimization of these parameters by existing experimental Fricke G-values, the present model estimates the yields of OH at the microsecond timescale after an irradiation, in a unified manner from electrons to heavy ions. The predicted yields of OH around the nanosecond timescale after an irradiation may be a relevant basis for a study on the mechanisms of radiation effects. This prediction by the present model was exemplified for electrons, photons and heavy ions (proton, helium, carbon, neon, argon and iron).