Response of LaBr3:Ce scintillation detector itself to fast neutrons

The LaBr3:Ce scintillator had been proved to be not only a promising gamma rays detector, but also a potential neutron detector. This dual response performance provided a possibility for the application of the LaBr3:Ce scintillator in neutron-gamma joint survey. However, the reported application of the detector in neutron detection depended on time-of-flight technique, which limited its application in the actual radiation field. To make the detector be useful for neutron measurement in actual mixed neutron-gamma fields, the responses of the LaBr3:Ce detector itself to fast neutrons were studied. Some specific neutron-induced peaks emitted in the neutron inelastic interaction with the detector were proposed. Based on these peaks, the LaBr3:Ce detector could be directly applied to neutron detection without time-of-flight technology. The response relationship between the counts of these neutron-induced gamma peaks in energy deposition spectrum of the detector and neutron ambient dose equivalent exhibited good linearity. The verification experiments were conducted with a 3 in x 3 in LaBr3:Ce detector in the reference calibration field formed by the Am-241-Be neutron source. In the neutron ambient dose equivalent rates range from 14.6 mu Sv h(-1) to 183.0 mu Sv h(-1), the linear response relationship was proved available. The studied results provided foundation for simultaneous neutron and gamma ambient dose equivalent measurements based on the LaBr3:Ce detector in mix radiation fields.