A compact scintillator-based detector for high energy neutron spectrometry

A compact neutron spectrometer consisting of a 6 mm × 6 mm × 120 mm prism of EJ-276 plastic scintillator capable of pulse shape discrimination coupled to a single silicon photomultiplier is described. In principle this device will be capable of spectroscopic measurements exceeding 100 MeV using unfolding analyses with detector response functions measured at neutron time-of-flight facilities. A characterisation of the device is described and illustrated with measurements of the detector response made at three fast neutron facilities with energies between 5.0 MeV and 63.5 MeV. Nearly mono-energetic detector response functions were used to produce neutron energy spectra by unfolding light output distributions measured with the detector in the energy range of interest.