Neutron Response of the EJ-254 Boron-Loaded Plastic Scintillator

Organic scintillators doped with capture agents provide a detectable signal for neutrons over broad energy range. This work characterizes the fast and slow neutron response of EJ-254, an organic plastic scintillator 5% natural boron loading by weight. For neutrons, primary mechanism light generation in is n-p elastic scattering. To study response, proton yield EJ-254 was measured at 88-Inch Cyclotron Lawrence Berkeley National Laboratory. Using broad-spectrum source double time-of-flight technique, obtained range approximately 270 keV to 4.5 MeV determined be agreement other comprised same polymer base. isolate AmBe polyethylene moderator made incident on surrounded array EJ-309 observation detectors. Events target coincident signature 477.6 $\gamma$ ray (resulting from deexcitation residual $^{7}$Li nucleus following capture) were identified. Pulse shape discrimination used evaluate temporal differences scintillation signals arising $\gamma$-ray fast/slow interactions. Clear separation between not achieved feature observed overlap both bands. Taking into account electron nonproportionality, neutron-capture 89.4$\pm$1.1 keVee.