Pulse-shape discrimination of the new plastic scintillators in neutron–gamma mixed field using fast digitizer card

Comparison of Neutron-Gamma Separation Qualities of Various Organic Scintillation Materials and Liquid Scintillator LSB-200

In this work, we compare the pulse-shape discrimination (PSD) properties of newly developed liquid scintillator LSB-200, EJ-299-33A, BC-501A, stilbene, p-terphenyl, and Hidex Aqualight in neutron field generated by the LVR-15 reactor with silicon filter utilization. Pulses from the scintillators are processed by the Neutron-Gamma spectrometer. This spectrometric system with fast digitizer card contains two analog–digital converters with a resolution of 12 bits and sampling frequency 500 × 106 Hz. For photomultiplier linearity improvement, the active divider has been used. Measured data from scintillators have been processed using the integration method and compared. The results are presented.

Enhanced performance of a pulsed neutron detector by the plastic scintillator with a photonic crystal

A detector based on the plastic scintillator film with large-area photonic crystals has been designed and demonstrated for measuring pulsed neutron flux. Compared with the reference detector, the neutron sensitivity and the gamma sensitivity of the detector using the scintillator film with photonic crystals were enhanced by more than 20%, which is attributed to the improved light extraction efficiency and the controllable angular profile of scintillation light by the photonic crystal. The application of the photonic crystals is beneficial to the improvement of the signal-to-noise ratio of the detector in the calibration experiment, thus expanding the lower limit of the measurable neutron flux without sacrificing the ratio of the neutron sensitivity to the gamma sensitivity. This research indicates that photonic crystals play an important role in the fields where scintillation photons need to be extracted and collected as many as possible.