Developments in mathematical expressions to map 3D ionization cluster size distribution in the nanodosimeter

Nanodosimetry strives to link phenomenological dosimetric concepts like radiation quality and relative biological effectiveness to measurable physical quantities related to the track structure of ionizing radiation. The ultimate goal of nanodosimetry is to determine novel dosimetric quantities such as ionization cluster size distribution. The ionization cluster size is defined as the number of ionizations generated in a target volume of nanometer scaling (DNA dimension) by a primary particle and its secondary electrons. The indigenously fabricated nanodosimeter consists of a positive ion detector made up of 576 holes in 52 arrays where each hole represents a detector. At present, the nanodosimeter gives the cumulative signal which is collected from all the 576 detectors. In order to get ionization cluster size distribution three dimensionally, it is necessary to isolate the signal produced by the individual detector. As the detector structure has a common detector between two array of detectors, it is possible to isolate the signal by measuring the signal corresponds to each array of detectors and solving a series of linear equations