Low-background Shielding for a Well-type Ge Detector

Abstract

A lead-shielding was constructed for a welltype Ge detector to utilize low-level r spectrometry. Background counting rate was investigated under lead thickness of 5-25 cm. It has been confirmed that selection of low activity materials for the construction of the detector has advantage to reduce the contribution of background deu to natural radioactivities. N₂ gas was helpful to reduce the contribution of atmospheric radon daughters especially during ofd ventilation period.