Optimization and characterization of a coincidence beta-ray spectrometer.

Appl Radiat Isot

Department of Physics and Astronomy, McMaster University, Hamilton, L8S 4L8, Canada.

Published: February 2024

Aimed at beta spectrometry and dosimetry for mixed beta-gamma fields, a Si-plastic scintillator coincidence beta-ray spectrometer has been developed. The spectrometer collects pure beta-ray spectra by rejecting the gamma-ray detection events through coincidence. Both pulse height and arrival time of each detection event were recorded in list mode by a compact digital processing system. Spectral measurements were carried out using mixed beta-gamma fields from Sr/Y and Cs sources for various beta and gamma count rates to evaluate the system performance. Coincidence beta spectra were collected for four fixed beta count rates (7.3-241 cps) from Sr/Y while the gamma count rate from Cs was varied from 500 to 8000 cps. The coincidence beta spectrum was stable and unperturbed by the gamma detection events for most measurements while notable perturbation was observed in the low energy region when the beta to gamma count ratio is very low.

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http://dx.doi.org/10.1016/j.apradiso.2023.111144DOI Listing

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