Speaker
Description
Radon emanation remains a dominant background in rare-event search experiments such as neutrinoless double beta decay and dark matter detection, motivating the development of high-sensitivity assay systems for material screening and detector validation. As a noble gas, radon can outgas of detector materials and circulate within experimental volumes, making it particularly challenging to mitigate. Its short-lived progeny can plate out onto detector surfaces, introducing long-lived radioactive contamination that can mimic or obscure rare signals.
This work presents the development of a low-background radon assay facility at the University of Windsor in Canada. The system is based on electrostatic collection chambers (ESCs), which detect radon by collecting positively charged progeny onto a detector surface using an applied electric field, followed by alpha spectroscopy. Multiple detector volumes, ranging from 5 L to 15 L, are implemented to study performance and optimize sensitivity. In addition, alternative designs are being explored to improve collection efficiency, including scintillation light collection, larger-area PIN diodes, and modified detector geometries.
The facility is designed to operate multiple ESCs with low level of background inside a clean room, targeting sensitivities at the level of tens of μBq. It is intended to serve as a central radon assay platform in Canada, supporting material screening and radon detector R&D for next-generation low-background rare-event search experiments.