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

Abstract

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 Co-60. For a 2.5-cm-thick 95 cm(3) crystal the results were SE/FE = 0.000 48 0.000 20 and 0.003 25 0.000 24 for 1173 and 1332 keV gamma-rays, respectively, and DE/FE = 0.000 90 0.000 17 and 0.003 41 0.000 11 for 1173 and 1332 keV, respectively. For a 3.0-cm-thick 84 cm(3) crystal the results were SE/FE = 0.000 67 0.000 32 and 0.003 79 0.000 27 for 1173 and 1332 keV respectively, and DE/FE = 0.001 05 0.000 28 and 0.004 29 0.000 16 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.