Europium-doped barium halide X-ray scintillators

Single crystals of europium-doped barium chloride, bromide, and iodide were investigated under x-ray and γ-ray excitation. The Eu2+-related x-ray excited luminescence is at 402, 404, and 425 nm for the chloride, bromide, and iodide, respectively. BaCl2:Eu2+ has the most promising scintillation properties of the systems investigated. The light yield is about 20,000 ± 2,000 photons per MeV of absorbed γ-ray energy, the energy resolution for the 662 keV photopeak is 9% ± 1%, and the scintillation decay time is (390 ± 40) ns. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)