Scintillation Properties of LiF/(K0.75Rb0.25)2CuCl3 Composites for Thermal Neutron Detection

K 0.75 Rb 0.25 ) 2 CuCl 3 composites were developed and their scintillation properties were investigated.Samples with mass ratios of LiF to (K 0.75 Rb 0.25 ) 2 CuCl 3 of 1:3, 1:2, 1:1, 2:1, and 3:1 were prepared, and the 1:3 and 1:2 samples showed the highest signal intensity in the pulse height spectra under thermal neutron irradiation using 252 Cf.The signal intensities corresponded to light yields below 9000 photons/neutron.The estimated / ratio of the 1:3 sample was high (0.62), and the high / ratio characteristic was also observed in the commercial LiF/ZnS:Ag composite.The temperature dependence of X-ray-induced scintillation spectra from room temperature to 200 showed that the emission intensity of (K 0.75 Rb 0.25 ) 2 CuCl 3 decreased more significantly at high temperatures than that of the lithium glass GS20.