Towards a compact experimental setup for gas-based microdosimetry

Microdosimetry measures the stochastics of imparted energy at the micrometre scale, and is a reliable experimental technique to monitor complex radiation fields such as those used in hadron therapy. At the Legnaro National Laboratories of INFN, miniaturized gas-based microdosimeters were developed specifically for this kind of applications. However, their use outside research facilities has been hindered by the encumbrance of the gas-flow system which is used to preserve gas purity and of the high-resolution analog electronic chain. To overcome this drawback, a new detector designed to work without gas flow was developed recently. The stability and reproducibility of its response in sealed conditions were studied in two measuring shifts one year apart from each other, both with the analog electronic chain and with a compact digital acquisition system. Preliminary results confirm the possibility to operate the detector with a very compact experimental setup, which could be a major advantage in clinical facilities.