Tl2LaCl5 (Ce3+): New Fast and Efficient Scintillator for X- and   {\gamma}-ray detection
  Scintillation properties of the new Tl2LaCl5: xCe3+ where x = 0, 0.5, 1 and 10 mole % (TLC: Ce3+) single crystals are presented. Two zones vertical Bridgman technique is used for the growth of this scintillation material. High Z-number (79) of this material offer excellent detection efficiency for X- and {\gamma}-rays. Grown samples are characterized under X- and {\gamma}-rays excitation in order to find the emission wavelength, energy resolution, light yield, and decay time. Emission spectra exhibit Ce3+ emission bands between 350 - 550 nm and peaking at 389 nm. The obtained energy resolution and light yield increases with high Ce-concentration. Energy resolution and light yield of 10%Ce-doped sample are found to be 6.9% (FWHM) and 51,000+-5000 ph/MeV, respectively at room temperature. For the grown samples, two exponential decay time constants are found. The measured decay time constants showed variation in their values with respect to Ce-concentrations in the host crystal. Fast decay time constant of 31 ns with 87% light emission is found for 10%Ce sample. Scintillation results suggested that TLC will be one of the promising next generation scintillator for the medical imaging techniques such as Positron Emission Tomography (PET). 
H. J. Kim, Gul Rooh, Sunghwan Kim
cond-mat.mtrl-sci