Fluorescence Processes and Scintillation of CeF3\text{}_{3} Crystal Excited by UV and X-Ray Synchrotron Radiation

Photoluminescence properties of CeF$\text{}_{3}$ have been investigated. Two kinds of emitting centers have been identified: regular Ce$\text{}^{3+}$ sites exhibiting two close emission bands (285 and 300 nm) and a fast fluorescence (20 ns) and several physically different perturbed Ce$\text{}^{3+}$ sites giving rise to a broad emission band near 340 nm and a longer fluorescence (30-40 ns) the decay time of which varies with wavelength. An energy transfer occurs between these two kinds of centers. Scintillation properties have been studied under UV and X-ray excitation. The additional fast decay always observed at short time under ionizing radiation is interpreted by a temperature dependent luminescence quenching phenomenon due to high excitation density