Online neutron/gamma discrimination and source detection using CLYC(Ce) scintillator: A sequential approach

We develop a sequential approach for online neutron/gamma discrimination and source detection using CLYC(Ce) scintillator. This approach consists of a dynamic k-means clustering algorithm, a density-based filter and a sequential probability ratio test. Compared to traditional methods, the proposed one has three advantages: (a) it does not require a prior threshold value for pulse shape parameter (PSP), (b) it automatically drops troublesome pulses which cannot be easily classified as neutron or gamma-ray, (c) it makes decision of whether a source exists during the detection (when the received pulses are adequate) instead of after a rigid detecting period. Experiment results show that under a neutron flux density of 11.16/cm² s, the average detection time for a ²³⁹Pu–Be source is 0.56 s for 95% confidence coefficient and 0.91 s for 99% confidence coefficient.