Cs₂Li(Na)Gd_(1-x)Ce _xCl(Br) crystal scintillators for radiation detection

We grow Cs₂Li(Na)Gd_(1-x)Ce_xCl ₆(Br) crystal scintillators by using Bridgman method for radiation detection (where x = 0.01, 0.1). Grown crystals are all Elpasolite and cubic structure that it is easy to grow even if they are all hygroscopic. X-ray excited luminescence spectra of the subject crystals showed broad emission peaks between 350 and 450 nm, with two overlapping peaks. This emission is caused by transitions from the lowest 5d excited state of Ce³⁺ to the two spin orbit split ²F_5/2 and ²F_7/2 ground state levels. Since the transition is favored, we expect fast decay time and high light output. We measured energy resolution and decay time of grown crystals by using gamma radiation source. Since the grown scintillation crystals contained gadolinium (Gd) which has high Z-number and could be used to efficiently detect gamma rays or x-rays in many applications such as computerized tomography (CT), positron emission tomography (PET), single photon emission computed tomography (SPECT) and homeland security. Also lithium (Li) and Gd contained crystals could be promising candidates for neutron detection.