Radiolysis of the Fricke Dosimeter with ⁵⁸Ni and ²³⁸U Ions:  Response for Particles of High Linear Energy Transfer

Abstract

The radiation chemical yields of the Fricke dosimeter have been determined for incident nickel and uranium ions with energies of up to 470 and 3780 MeV, respectively. Track segment yields have been determined from the observed energy dependences. Experiments utilizing both aerated and deaerated solutions indicate that at the very high values of linear energy transfer (LET) exhibited by these ions in water (a maximum of 5000 and 17 000 eV/nm, respectively) a significant fraction of radicals escape from the track. The radiation chemical yield of H atoms for both ions is found to be ∼10% of the value with fast electrons. The data also suggest that there is a substantial yield of an oxidizing species produced by particles of very high LET. A comparison of the results with particles of lower LET is made.

Irradiation-driven molecular dynamics: a review

“…The transport of radicals by the collective flow does not only propagate the radicals much faster than diffusion but also prevents their recombination, both by their spreading and by creating harsh conditions in which the formation of the O-O bond is suppressed [33]. These results are in line with the observations made for the only reported data for water radiolysis with very high-LET ions [79], where unusually large amounts of radicals escaped ion tracks.…”

Hydrogen Peroxide Production in the Radiolysis of Water with Heavy Ions

“…The effect of track structure on radiolytic yields with high LET particles has been investigated in aqueous solutions. − Most of the results concern the yields of molecular hydrogen and of the radicals formed by water radiolysis (H, OH, HO 2 ). No experimental data are available on the yields of hydrogen peroxide obtained with heavy ions as a function of the concentration of added scavengers, and there are few studies at neutral pH.…”

The role of shock waves on the biodamage induced by ion beam radiation

“…• Has the increased amount of radicals escaping high-LET ion's tracks observed by LaVerne and Schuler (1996) been observed by other authors? Has some explanation to this effect been yet proposed?…”

“…Also, an experiment of water radiolysis for very high-LET Ni and U ions was reported by LaVerne and Schuler (1996). In this experiment, it was observed that a significant fraction of free radicals could escape the ion's track.…”