Pure CaF2 crystal for fast neutron detection.

Pure CaF 2 crystals have been widely used for optical functional crystals due to their good optical properties, mechanical properties, and chemical stability. This study discovered the crystal's pulse shape discrimination (PSD), proving it a promising scintillator for fast neutron detection via the 40Ca neutron capture reaction. Luminescence emission spectra were studied by X-ray luminescence measurements. The maximum emission peak was observed between 250 and 300 nm, corresponding to self-trap exciton emission. The crystal response to gamma, alpha, and neutron were studied under 137Cs, 241Am, and 252Cf radiation sources, respectively. The difference in gamma and alpha decay times enabled the PSD capability of pure CaF 2. Large neutron reaction cross-sections, PSD capability, and good chemical stability make pure CaF 2 crystal candidates for fast neutron beam monitoring detectors. Moreover, the crystal can be used for 40Ca(n,p)40K and 40Ca(n,α)37Ag neutron capture cross-section study. • The paper reports the first study of pure CaF 2 crystal for fast neutron detection. • Light yield of the crystal is 7100 ± 700 photons/MeV. • The crystal has good linearity response, energy resolution is about 9.1% at 662 keV. • PSD was studied for gamma-alpha (FOM = 0.85) and gamma-neutron (FOM = 0.80) separation. [ABSTRACT FROM AUTHOR]