Chemical Yields of Ionizing Particles in Aqueous Solutions: Effect of Energy of Protons and Deuterons

Abstract

Ferric ion yields are reported for protons in the energy range from 0.3 to 2.0 Mev and for deuterons in the range from 3.5 to 21.5 Mev. Variations of beam energy using protons and deuterons was accomplished by placing appropriate aluminum absorbers between the target box window and the cell. The charge input to the solution was neutralized by the electron current flow from ground through a 105 ohm resistor to a platinum wire immersed in the solution beyond the range of the particles. Mica windows were employed on the irradiation cells and yield-absorber curves were obtained for aluminum and mica absorbers using 2.5 Mev protons to correct for energy loss in the mica. The aqueous solutions irradiated consisted of (a) 1mN FeSO4, 0.8 N H2SO4, lm[image] NaCl and (b) 1mN FeSO4, 10 m[image] CUSO4, and 10mN H2SO4 Go(Fe+++), ferric ions produced/100 ev varied from 10.86 to 6.90 as the deuteron energy decreased from 21.16 to 3.47 Mev andGo(Fe+++) decreased from 8.00 to 7.16 as the proton energy decreased from 1.99 to 0.29 Mev. Go(Fe+++-Cu++) increased from 1.02 to 1.81 over the deuteron energy range, 21.24 to 3.35 Mev and Go(Fe+++ Cu++) increased from 1.58 to 2.60 over the proton energy range 1.99 -0.29 Mev. The significance of these yields in terms of free radical and molecular product distribution along the track of ionizing particles in aqueous solutions is discussed.