Gamma Detection with Point-Contact HPGe: DEGA Prototype

A brief overview of a new point-contact (PC) high-purity germanium (HPGe) detector will be given. The new detector, named GROVER, combines GRETA and LEGEND technology to provide unprecedented dynamic range (gamma-ray efficiency and resolution) in a single, relatively small package. GROVER was funded through an ORNL ICE award project. The cryostat houses 4 p-type point-contact detectors with precut geometries of 8-cm diameter and 7-cm length. The crystals have no center hole and a thin entrance window for low-energy efficiency. The unusual geometry is modeled after GRETA for efficient packing of up to 30 modules in a 4pi shell with an expected efficiency of roughly 30% at 1 MeV. The GROVER detector is a prototype designed for the DEcay Germanium Array (DEGA) of the FRIB Decay Station (FDS). The detector will also be deployed at ORNL for various work involving the reactor HFIR. The prototype is currently being characterized, and waveform analysis filters are being optimized.