Measurement of single- and double-escape HPGe efficiency ratios for 60 Co

As a by-product of another measurement, ratios of the single-escape (SE) and double-escape (DE) efficiencies relative to the full-energy-peak efficiency (FE) have been measured for two HPGe detectors for 60Co. For a 2.5-cm-thick 95 cm3 crystal the results were SE/FE = 0.00048+/-0.00020 and 0.00325+/-0.00024 for 1173 and 1332 keV gamma-rays respectively, and DE/FE = 0.00090+/-0.00017 and 0.00341+/-0.00011 for 1173 and 1332 keV respectively. For a 3.0-cm-thick 84 cm3 crystal the results were SE/FE = 0.00067+/-0.00032 and 0.00379+/-0.00027 for 1173 and 1332 keV respectively, and DE/FE = 0.00105+/-0.00028 and 0.00429+/-0.00016 for 1173 and 1332 keV respectively. These measurements may be of relevance in connection with Monte Carlo calculations of HPGe detector efficiencies, and may also suggest a path towards improved atomic cross-section measurements.