A neutron detector may include a neutron counter and a plurality of optical fibers
peripherally arrayed around the counter. The optical fibers have thereon a layer
of scintillator material, whereby an incident fast neutron can transfer kinetic
energy to nuclei in one or more of the optical fibers to produce recoil protons.
The recoil protons interact with the coating to produce scintillation light that
is channeled along the optical fiber or fibers with which the neutron interacted.
The slowed neutron passes into the neutron counter where the neutron effects generation
of a signal coincident with the light produced in the optical fibers in which the
neutron deposited energy.