Development of Field Deployable Alpha-In-Air Monitor System Based on Resistive Electrode Thick Gas Electron Multiplier

Abstract

In a radiological emergency, the emergency response team needs to identify potential health hazards in the environment. One of the hazards is particles that emit alpha radiation in the environment. It is challenging to detect alpha radiation and dangerous gases reliably and accurately from remote distances, to secure the safety of response team members. The development of a compact, robust alpha-in-air monitoring unit that is suitable for field tests and employs a resistive electrode thick gas electron multiplier (RETGEM) is underway at Canadian Nuclear Laboratories. A hybrid RETGEM detector with a double-RETGEM structure was constructed and tested by using a mixture of P-10 counting gas with ambient air at various ratios. Alpha particles were emitted by a calibrated Cm-244 source. After adjusting the parameters of the detector for optimal work conditions, an electronic read- out signal induced by the ionizing radiation of alpha particles was successfully observed. This paper will present the approach of the double-RETGEM structure and lessons that we have learned for addressing detector-related issues to obtain electron multiplication in the ambient air.