Rapid compton camera imaging for source terms investigation in the nuclear decommissioning with a subset-driven origin ensemble algorithm

Abstract

As the nuclear facilities (e.g. nuclear power plants) built in the last century gradually reached their life cycle, some nuclear facilities entered the decommissioning stage. Radioactivity measurement runs through the entire process of nuclear decommissioning, and source terms investigation is particularly important. Compton camera is a new technical method in nuclear facility decommissioning, and has the unique advantage of direct visualization of radiation pollution in nuclear facilities. This paper proposed a subset-driven origin ensemble algorithm with resolution recovery, which is suitable for rapid reconstruction of large space via Compton cameras. The proposed algorithm can correct the projection data deviation caused by the inherent spatial and energy resolution of the Compton camera as well as the Doppler broadening effect, and realize the rapid positioning of the spatial radiation source within a few seconds. We used both the Monte Carlo simulation based on Geant4 and the experiments of the double-layer Compton camera prototype to verify the feasibility of this new algorithm in real-time radiation source detection. This research can provide a promising method for the spatial radiation field reconstruction of nuclear facilities based on Compton cameras and the refined management of nuclear facilities decommissioning.