Optical and scintillation properties of pure and Ce super(3+) doped GdBr sub(3)

Optical and scintillation properties of pure GdBr sub(3) and GdBr sub(3):2% Ce super(3+) are presented. Under optical excitation, Ce super(3+) luminescence is observed between 350 and 550 nm with maxima at 413 and 446 nm. The Stokes shift is approximately 3400 cm super(-1). GdBr sub(3):2% Ce super(3+) shows a high light output of 44000 plus or minus 4000 photons per MeV of absorbed gamma -ray energy. The scintillation decay curve can be characterized by three decay components with decay times of 20.0 plus or minus 0.1, 212 plus or minus 12 ns and 13.5 plus or minus 0.5 mu s, respectively.