Investigation of spectral emulation for HPGe gamma-ray response generation

Abstract To address high-count-rate conditions in advanced reactor online monitoring, a novel combined simulation-emulation approach is investigated. High count rate dependent gamma-ray spectra are generated using spectral emulation hardware. The performance of the emulator was assessed using measured gamma-ray spectra of progressive complexity including Cs-137, Co-60, and multi-line Eu-154 sources at different count rates. The experimental spectra and their corresponding emulated spectra from the three sources were compared. The emulation results verified that key characteristics of the measured spectra were maintained in the emulated spectra. The study proceeded with the emulation of a simulated gamma-ray spectrum of pebble bed reactor fuel. Spectral distortions were observed as the count rate increased. It was concluded that the emulator is capable of generating accurate HPGe detector responses, including for high count rates conditions.