Bismuth Germanate: A High-Z Gamma-Ray and Charged Particle Detector

The room-temperature scintillation characteristics of single crystals of Bi4Ge3O2 under gamma-ray and alpha-particle excitation have been determined. The wavelength of maximum intensity in the scintillation spectrum is 480 nm. A decay constant of 0.30 microseconds was measured. Scintillation efficiency (pulse height) varied linearly with gamma-ray energy, E, and the resolution varied as E-1/2. 8% pulse height relative to NaI(Tl) with 15% resolution was measured for a 2.2 cm × 1.7 cm crystal under excitation by Cs137 0.662 Mev gamma-rays.