LiBaF3, a thermal neutron scintillator with optimal n-γ discrimination

We report on the scintillation properties of a LiBaF3 crystal when irradiated with thermal neutrons or gamma rays. The scintillator exhibits cross luminescence and self-trapped-exciton luminescence. The former does not show up under thermal neutron irradiation, whereas both give a response under gamma irradiation. This offers a unique opportunity for thermal neutron-gamma discrimination. The effectiveness of the method is demonstrated.