Optimizing a Broad Energy High Purity Germanium (BEGe) Detector Operated at Shallow Depth in Abu Dhabi

Abstract

In this work we present the characterization of a Broad Energy Germanium (BEGe) type High Purity Germanium (HPGe) detector, with a carbon fiber entrance window thickness of 0.6 mm and an active area of 6305 mm2, operated at shallow depth (~ 8m) in Abu Dhabi, UAE. A 1.6 keV Full Width Half Maximum (FWHM) was obtained for the 662 keV peak of 137Cs. A muon veto was applied, reducing the background by 8 % (for energies greater than 100 keV). Flushing the volume around the detector endcap with nitrogen gas, to remove radon and thus its progeny, further reduced the background by ~3 %. A thorough analysis for the shaping filter parameters showed that the detector has better resolution at low rise-time values (2 - 5 us) especially for low energy gamma (<600keV), keeping the flattop value fixed at 1.1 us.