Influence of ionization cross-section data on the Monte Carlo calculation of nanodosimetric quantities

In this work, we discuss the effect of cross-section data in the determination of nanodosimetric quantities, such as ionization cluster-size distributions and mean cluster sizes. In particular, two different theoretical approaches to determine secondary electron distributions after proton interactions in nitrogen and propane were tested by means of a Monte Carlo code. The results show that differences of 10–15% in the cross-section data lead to differences of up to 10–20% in the calculated mean cluster sizes, especially at low energies, suggesting the need for new, reliable and consistent experimental cross-section data.