Electronic collisions with molecules of biological relevance.

Abstract

Experimental studies of radiation damage in living tissue indicate that it is not just the primary ionizing particle responsible for the bulk of the radiation damage, but also secondary species generated by the ionizing particle. There is much interest in how these secondary particles, commonly electrons, interact with bio-molecules and in particular DNA. In this thesis, I report relative triple differential cross section measurements for the electron impact ionization of formic acid, tetrahydrofuran and thymine. Formic acid can be considered one of the simplest building blocks for biological systems, particularly in the formation of glycine and amino acids. Tetrahydrofuran is a simple ring structure that can be used as a good approximation to the sugar component of the deoxyribose backbone. Thymine, together with cytosine, guanine and adenine, are the DNA bases and their interactions with electrons are considered to be of great importance. Single differential cross sections for elastic electron interactions with cytosine and thymine are also reported.