Point Source Function to Determine HPGe Detector γ-ray Peak Efficiency for Large Volume Samples

Based on HPGe spectrometers, the full energy peak efficiencies at different height sample radius were obtained by the ²⁴¹Am, ¹³⁷Cs, ⁶⁰Co mixed point sources, and the function parameters about the full energy peak efficiencies of point sources based on radius and height were fixed. The 59.54, 661.66, 1 173.2, 1 332.5 keV γ-ray’s detection efficiencies of 75 mm×25 mm sample were obtained，based on integrality radius and height of point sources. The detection efficiencies integrality by point sources function were consistent with the results of standard source and LabSOCS in 10%. Therefore, the calibration method of standard source is feasible. And this method was applied in calculating any shape sample. The integrality sphere source’s detection efficiency was consistent with the results of LabSOCS in 10%.