Low-energy Neutron Measurements with EJ-309 Liquid Scintillator Detectors

Year
2013
Author(s)
S. D. Clarke - Department of Nuclear Engineering & Radiological Sciences, University of Michigan
S. A. Pozzi - Department of Nuclear Engineering & Radiological Sciences, University of Michigan
C. Miller - Department of Nuclear Engineering & Radiological Sciences, University of Michigan
Mark A. Norsworthy - University of Michigan
Abstract
Two high-gain, low-threshold neutron measurements were conducted using EJ-309 organic liquid scintillator detector. In the first measurement, neutrons were generated by a 2 MeV proton beam striking a 304 stainless steel target. The measurement was sensitive to neutrons depositing as low as 175 keV (10 keVee) in the scintillator. The second measurement was conducted using a Cf-252 source and two EJ-309 detectors in a neutron time-of-flight setup. Simulations were conducted of both measurements using the MCNPX-PoliMi code. The well-known Cf-252 neutron spectrum allowed validation of the simulated results. Pulse shape discrimination is difficult at such low thresholds, but the results indicate that low-energy neutron measurement with organic liquid scintillators may be feasible with improved pulse shape discrimination techniques.