Gamma and neutron separation using emission wavelengths in Eu:LiCaI scintillators

Abstract

Abstract Scintillators have long been known as radiation detectors and are still used in various applications. Recently, scintillators containing 6Li have been developed as neutron detectors and have attracted attention. 6Li absorbs thermal neutrons and emits α+3H, which is promising as a neutron detector if it can be separated from background gamma rays. We have been developing Eu:LiI–CaI2-based scintillators (Eu:LiCaI) for this purpose. In scintillator detectors, waveform information is generally used to distinguish particles such as neutrons and gamma rays. We propose a new particle identification method using emission wavelength information. In this study, experiments were conducted using Eu:LiCaI crystals, multi-pixel photon counter optical sensors, and long-wavelength cut filters to verify the proposed method. The results of irradiating a 252Cf neutron source and a 60Co gamma-ray source indicate that there is a particle dependence on the output signal ratio with and without filters. This indicates that different types of radiation particles have different emission wavelengths. This is the first demonstration of a wavelength-based particle identification method.