A realistic solution of overcoming disadvantage of Compton suppression spectrometer

To achieve low detection limits for radionuclide analysis, Compton continuum suppression gamma-ray spectrometer has been used for several decades. The most serious disadvantage arises when radionuclides measured have cascade gamma emissions. This is a major limitation of the technique in environmental sample analysis. The digital list-mode data acquisition techniques in conjunction with time stamped pulse analysis method presented in this paper recovers the undesired full-energy-peak (FEP) coincidence losses for cascade radionuclides while retains suppression of true Compton events to keep the improved detection limit, thus extending the usefulness of the anti-Compton spectroscopy. In this study, software are developed to analyse the radionuclides with a relative simple decay scheme, such as ²²Na, ⁶⁰Co and ⁸⁸Y, and a complex decay scheme, such as ^125Sb, ¹³⁴Cs, ¹⁵²Eu and ¹⁵⁴Eu. The results indicated that in the reconstruct anticoincidence spectra the FEP restoration efficiency, both for minor and major peaks, is near 100%.