Transport of secondary electrons and reactive species in ion tracks

TL;DR

This paper analytically investigates the transport and effects of secondary electrons and reactive species generated by ions in tissue-like media, providing insights into energy distribution, radical formation, and potential shock wave initiation.

Contribution

It introduces an analytical model for secondary electron transport, energy deposition, and reactive species evolution in ion tracks, advancing understanding of ion-matter interactions.

Findings

Radial energy loss distribution informs initial dose modeling.

Distribution of solvated electrons in water is characterized.

Reactive species formation and diffusion are quantitatively analyzed.

Abstract

The transport of reactive species brought about by ions traversing tissue-like medium is analysed analytically. Secondary electrons ejected by ions are capable of ionizing other molecules; the transport of these generations of electrons is studied using the random walk approximation until these electrons remain ballistic. Then, the distribution of solvated electrons produced as a result of interaction of low-energy electrons with water molecules is obtained. The radial distribution of energy loss by ions and secondary electrons to the medium yields the initial radial dose distribution, which can be used as initial conditions for the predicted shock waves. The formation, diffusion, and chemical evolution of hydroxyl radicals in liquid water are studied as well.