Nanodosimetry - on the tracks of biological radiation effectiveness

Biological effectiveness of a certain absorbed dose of ionizing radiation depends on the radiation quality, i. e. the spectrum of ionizing particles and their energy distribution. As has been shown in several studies, the biological effectiveness is related to the pattern of energy deposits on the microscopic scale, the so-called track structure. Clusters of lesions in the DNA molecule within site sizes of few nanometers play a particular role in this context. This work presents a brief overview of nanodosimetric approaches to relate biological effects with track structure derived quantities and experimental techniques to derive such quantities.