Coincidence corrections for a multi-detector gamma spectrometer

List mode data acquisition has been utilised in conjunction with a high efficiency gamma-gamma coincidence system, allowing both the energetic and temporal information to be retained for each recorded event. Collected data is re processed multiple Limes to extract any coincidence information from the gamma-spectroscopy system, correct for the time-walk or low-energy events, and remove accidental coincidences horn the projected coincidence spectra. The time-walk correction has resulted in a reduction in the width of the coincidence delay gate of 18.4 +/- 0.4%, and thus an equivalent removal of 'background' coincidences. The correction factors applied to similar to 5.6% of events up to similar to 500 keV for a combined Cs-137 and Co-60 source, and are crucial for accurate coincidence measurements of low-energy events that may otherwise be missed by a standard delay gate. By extracting both the delay gate and a representative 'background' region for the coincidences, a coincidence background subtracted spectrum is projected from the coincidence matrix, which effectively removes similar to 100% of the accidental coincidences (up to 16.6 +/- 0.7% of the total coincidence events seen during this work). This accidental-coincidence removal is crucial for accurate characterisation of the events seen in coincidence systems, as without this correction false coincidence signatures may be incorrectly interpreted. Crown Copyright (C) 2014 Published by Elsevier B.V. All rights reserved.