Radical Yield Measurements in Irradiated Aqueous Solutions: II. Radical Yields with 10.9-Mev Deuterons, 21.3- and 3.4-Mev Alpha Particles, and B(n, α) Li Recoil Radiations

Abstract

Solutions containing ferric sulfate, cupric sulfate, and formic acid in 0.01 N H2SO4 were irradiated with ionizing radiations of high linear energy transfer (LET), and the product yields measured. Information has thus been obtained concerning the effect on the yield of free H and OH radicals of (1) increasing concentration of radical scavengers, and (2) increasing LET of the incident radiation. Measurements have also been carried out of the yield of ferric ion in aerated and de-aerated ferrous sulfate solutions in 0.01 N and 0.8 N H2SO4, induced by similar types of radiation. Striking departures are observed from the predictions of simple theories based on homogeneous kinetics which have proved adequate in interpreting the effects of gamma-rays on the same systems. It is concluded that with radiations of high LET even the secondary stages of the reaction mechanism take place in track zones in which the concentrations of the intermediate chemical species are changing rapidly with time.