Characterization and performance of co-axial HPGe detectors

High purity germanium (HPGe) detectors are deployed globally for gamma-radiation spectroscopy due to their superior energy resolution. In this work, the essential characteristics of n and p-type HPGe detectors, such as energy resolution, efficiency, minimum detectable activity (MDA), and peak shape were studied for the purpose of characterization and performance optimization. The results are obtained for various source-detector configurations in a wide energy range of 40–1408 keV using gamma sources, such as 109 Cd, 57 Co, 137 Cs, 54 Mn, 65 Zn, 60 Co, and 152 Eu. Scanning (distance, lateral, and radial) of the detectors was performed using different gamma sources to understand the orientation of the crystal with its active volume and counting efficiency and to characterize the geometry in detail. The ambient background around the n-type HPGe was reduced using Pb-shielding. As a result, an 85.85% suppression was observed in the mean integral window of 40–2700 keV. The characterization and performance tests of the detectors convincingly suggest that both the detectors can be deployed for environmental radioactivity explorations.