Abstract:
Calibrating the detection efficiency accurately is the key work to the gas activity measurement by HPGe detector gamma spectrometer method. The gas samples operation is difficult because of their state and characters, especially when the half-lives of gases are short. It is not convenient to calibrate the detection efficiency by real gas calibration source. The paper introduces a new calibration source named simulation gas calibration source, it can replace gas standard source to calibrate detection efficiency of HPGe detector and to monitor the stability of the detection efficiency daily. The matrix density of the simulation gas calibration source is only 0.043 g/cm
3 and the self-absorption of this source is less than 0.5%. The efficiency calibrated by this source is in coincidence with reference value well.