Pulse-Shape Discrimination Capabilities of the RMD Plastic Scintillator as Compared to the EJ-299-33 Plastic Scintillator

Advances in plastic scintillation compositions have led to new scintillation detectors capable of correctly identifying neutron and gamma-ray photon pulses through pulse shape discrimination (PSD). The goal of this paper is to explore the PSD capabilities of a plastic scintillator produced by Radiation Monitoring Devices, Inc. (RMD) and compare it to both the EJ-309 liquid scintillator and the EJ-299-33 plastic scintillator [5]. Neutron time of flight data was taken from 252Cf for all the RMD plastic and EJ-309 detectors, and a PSD algorithm was applied to each detector. The study shows that the RMD plastic has adequate PSD, with a figure of merit of 0.86 for a threshold of 120 keVee. This compares favorably to the PSD for the EJ-299-33 figure of merit of 0.82, but the EJ-309 liquid detector gives a figure of merit of 1.44 at the same measurement threshold. In addition, the neutron detection efficiency for the RMD detector is within 3% of the EJ-299-33 detector, but the EJ-309 liquid detector is 1.6 times more efficient.