THE RESPONSE OF A HPGE DETECTOR WITH A BGO SHIELD TO HIGH-ENERGY GAMMA-RAYS

The response of a HPGe (82%) detector with a BGO anti-Compton shield has been studied for the 15.1 MeV gamma-rays produced by the reaction D(B-11,n gamma)C-12 and for the 6.13 MeV gamma-rays produced by a Pu-238-C-13 source. The energy deposited in the HPGe and in the BGO was measured for each detected gamma-ray. The sum energy and the spectra of the HPGe in anticoincidence with the BGO were obtained and compared to simulated spectra calculated with the GEANT libraries. The measured energy resolution for the 15.1 MeV gamma-rays emitted by C-12 is 209 keV. Due to the velocity (beta = 0.05) of C-12, the Doppler broadening contribution to the measured FWHM is 140 keV. For the 6.13 MeV gamma-rays emitted by the Pu-238-C-13 source, the measured energy resolution was 132 keV.