Luminescence and scintillation properties of TlCdCl₃ crystal

We report the photoluminescence and the scintillation properties of a newly developed thallium cadmium chloride (TlCdCl₃) crystal. This crystal will provide excellent detection efficiency for X- and γ-rays due to its high effective atomic number (Z_eff = 68.7) and density (ρ = 5.31 g/cm³). The crystal sample can be easily prepared from the melt using the Bridgman method. The photoluminescence band appeared near the wavelength of 450 nm under excitation at 270 nm. By tri-exponential equation fitting with a deconvolution of instrumental response, the photoluminescence decay time value was found to be approximately 24 ns (∼77.6%), 60 ns (∼19.8%) and 870 ns (∼2.6%). An X-ray-induced scintillation spectrum showed a broad emission band near the wavelength of 450 nm. The scintillation decay time constant was estimated to be approximately 2.6 ns (∼8%), 45 ns (∼47%) and 170 ns (∼45%) using a tri-exponential fitting. The scintillation light yield reached 2200 photons/MeV calibrated with a GSO commercial scintillator.