Leigh's new NSF grant will help him and his students establish a new electron spectrometer based on a magnetic beam principle to help mitigate traditional technological limitations of electron scattering experiments. 

Leigh Hargreaves with physics students

Once developed, the experiments Leigh proposes will allow detailed measurements of electron cross sections for two important biological compounds, uracil and thymine. The cross sections are key to understanding electron transport through biological matter. 

Professor Hargreaves joined the faculty fall 2014 and began building his electron scattering experiment based on a gift instrument from his home institution Flinders University Adelaide and mentor Professor Michael Brunger.

Pioneering work some 15 years ago demonstrated that low-energy electrons readily break DNA strands in biological tissue and are therefore genotoxic. This discovery contradicted conventional wisdom that such electrons were too low in energy to initiate chemistry. Moreover, given such electrons are created in copious quantities in radiation therapy, the research further suggested that cancer patients were receiving actual radiation doses higher than intended.

The physics community has since given much attention to biomolecules to better understand the nature of electron interactions with DNA. While significant advances have been made, technological limitations of electron scattering experiments have thus far precluded study of some of the most important targets. 

Leigh is committed to advancing the careers of young scientists and involving them in laboratory atomic physics. He expects to include three or more students per year, developing a variety of transferable skills in laboratory technology. The data collected by their experiments will facilitate advanced dosimetry modelling with the potential for improving cancer patient safety during radiation therapy.