Optimization of a GEM-based detector to measure tritium and discriminate against other radiation types

Abstract

Tritium poses a radioprotection issue, in the Canadian Nuclear industry due to the operation of its fleet of Canadian Deuterium Uranium (CANDU) heavy water reactors. Although it is a less penetrative radionuclide, tritium is shown to have a detrimental effect on the human body when ingested, inhaled or absorbed. GEM detectors have proven to be very useful in the detection of low energy ionizing radiation, with their ability to multiply electrons via avalanches and amplify the signal thereby increasing the ease of detection. This work aims to optimize the design of the collection plate of a GEM-based tritium monitor in order to discriminate between short and long-range beta particles and electrons. The THGEM gain was also investigated with experimental and computational modelling. Recommendations include modification of the collection plate and increasing the gain of the detector to improve the efficiency of tritium detection and discrimination against other radiation types.