A CRYOGENICALLY COOLED SINGLE-CRYSTAL BGO ANTI-COMPTON SPECTROMETER

The construction and experimental results of a novel compact anti-Compton spectrometer system are reported. The device consists of a large BGO scintillation crystal with a cylindrical well. Inside the well, a 56 mm diameter, 57 mm high (n-type) germanium crystal is mounted. The entire assembly is cooled down to 104 K. Scintillation light from the BGO crystal is detected by a 127 mm diameter PM tube. The assembly has the advantage of a compact design and the absence of any material between the Ge and the BGO crystal. A Peak-to-Total ratio of 0.60 is obtained with a Co-60 source and 0.74 with a Cs-137 source.