title: Estimation of yields of OH radicals in water irradiated by ionizing radiation.
abstract: 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).
authors.affiliation: Space and Particle Radiation Science Research Group, National Institute of Radiological Sciences 9-1, Anagawa 4, Inage-ku, Chiba 263-8555, Japan. yamag@nirs.go.jp
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Yamaguchi
authors.forename: Yukio
authors.initials: Y
authors.lastname: Uchihori
authors.forename: Nakahiro
authors.initials: N
authors.lastname: Yasuda
authors.forename: Masashi
authors.initials: M
authors.lastname: Takada
authors.forename: Hisashi
authors.initials: H
authors.lastname: Kitamura
mesh_terms: D003198:Computer Simulation; D004307:Dose-Response Relationship, Radiation; D017665:Hydroxyl Radical / Q000138:chemical synthesis* / Q000528:radiation effects*; D007700:Kinetics; D018499:Linear Energy Transfer; D008956:Models, Chemical; D011829:Radiation Dosage; D011839:Radiation, Ionizing; D014867:Water / Q000737:chemistry*
chemical_list: D014867:Water; D017665:Hydroxyl Radical