Scintillation performance of the TlSr2I5 (Eu2+) single crystal

TlSr₂I₅: Eu²⁺ is a newly discovered scintillator that show promising scintillation properties for X- and γ-ray spectroscopy applications. Two zone vertical Bridgman technique is used for the growth of this scintillator. Luminescence properties of the grown crystals are measured under X-ray excitation at room temperature. Pure and Eu²⁺ doped crystals contained broad emission bands between 445 and 670 nm peaking at 528 nm and 430-600 nm peaking at 463 nm, respectively. Energy resolution, light yield and decay time profiles are studied under 662 keV γ-ray excitation using ¹³⁷Cs radioactive source. Energy resolution of 4.2% (FWHM) is obtained for 3 mol% Eu²⁺ doped crystal. For the same sample, light yield of 70,000 ph/MeV is also obtained. Three and two decay constants are observed for the pure and Eu²⁺ doped samples, respectively at room temperature. Effective Z-number and density are found to be 61 and 5.30 g/cm³, respectively.