Scintillation properties of Ce-doped LiAlO2 for neutron detection

Abstract

Undoped and Ce-doped LiAlO2 single crystals, a novel neutron scintillator, were synthesized by the floating zone method, and the photoluminescence and scintillation properties were investigated. Under X-ray irradiation, all the synthesized crystals showed luminescence due to oxygen vacancies with decay time constants of 250 ns and 2 ¯s, and Ce-doped LiAlO2 crystals showed luminescence due to the 5d4f transition of Ce3+ with a decay time constant of 40 ns as well. In the pulse height spectra under neutron irradiation from 252Cf, the synthesized crystals exhibited thermal neutron peak, and scintillation light yields increased by doping of Ce. Furthermore, neutron and gamma-ray pulse shape discrimination was examined, and 0.5 and 1.0 % Ce-doped ones showed a distinction of neutron and gamma-ray events.