Scintillation characteristics of nonstoichiometric phases formed in MF2–GdF3–CeF3 system Part II. (M=Ba), scintillation of Ba1−xCexF2+x (0.1⩽x⩽0.45) fluorite type crystals

Among three different Ce-concentrations (10, 27 and 45 mol%) which we tested, the 27 mol% sample showed by far the best radiation hardness and the maximum fast component fraction in the luminescence. For this Ce-concentration, the scintillation intensity was about 30% of that in pure BaF2 (within a 1 μs gate) and comparable to that in CeF3. The decay constant of scintillation was about 38 ns. The melting curve of the Ba1−xCexF2+x solid solutions has a maximum at approximately 27 mol% CeF3. The congruent character of the melt with this composition, which should be related with specific structural defects configuration in anionic sublattice, could be the reason for the excellent radiation hardness observed in the Ba0.73Ce0.27F2.27 crystal.