Using the waveforms from a digital electronic system, an offline analysis technique on pulse shape discrimination (PSD) has been developed to improve the neutron-gamma separation in a bar-shaped NE-213 scintillator that couples to a photomultiplier tube (PMT) at each end. The new improved method, called the ``valued-assigned PSD'' (VPSD), assigns a normalized fitting residual to every waveform as the PSD value. This procedure then facilitates the incorporation of longitudinal position dependence of the scintillator, which further enhances the PSD capability of the detector system. In this paper, we use radiation emitted from an AmBe neutron source to demonstrate that the resulting neutron-gamma identification has been much improved when compared to the traditional technique that uses the geometric mean of light outputs from both PMTs. The new method has also been modified and applied to a recent experiment at the National Superconducting Cyclotron Laboratory (NSCL) that uses an analog electronic system.
@article{arxiv.2001.07518,
title = {Value-assigned pulse shape discrimination for neutron detectors},
author = {F. C. E. Teh and J. -W. Lee and K. Zhu and K. W. Brown and Z. Chajecki and W. G. Lynch and M. B. Tsang and A. Anthony and J. Barney and D. Dell'Aquila and J. Estee and B. Hong and G. Jhang and O. B. Khanal and Y. J. Kim and H. S. Lee and J. W. Lee and J. Manfredi and S. H. Nam and C. Y. Niu and J. H. Park and S. Sweany and C. Y. Tsang and R. Wang and H. Wu},
journal= {arXiv preprint arXiv:2001.07518},
year = {2021}
}