Characteristic of a Cs2LiLaBr6:Ce scintillator detector and the responses for fast neutrons

The elpasolite crystal CLLB is proposed to detect both γ-ray and thermal neutron events with the ability to distinguish them by pulse shape discrimination (PSD) method. Pulse shapes of γ-ray, alpha particle, thermal and fast neutron events were measured and determined that PSD can be performed to separate γ-ray from alpha and thermal neutron events with a Figure of Merit (FoM) 1.23. The γ-ray non-proportional response is less than 2% in the energy region of 59.6 keV-4438 keV. Fast neutron responses for CLLB scintillator were investigated and analyzed using deuterium tritium (DT) reaction neutrons. The activity of 511 keV γ-ray emitted by 78Br and 80Br can reaches up to ∼0.709 Bq⋅n−1, some high-energy events at 15 MeVee - 18 MeVee were found that generated according to the reaction 6Li(n, T)4He.