Developing and Test of Fast Neutron Detectors Array for Spectroscopy

Nine 100x100x600 mm3 plastic scintillators, formerly built for the neutron time of flight measurements at iThemba LABS, were refurbished. The position resolution of these detectors was determined using muon cosmic rays and coincident measurement techniques. Average position resolution of ∼ 4.28 cm (FWHM) was found. In order to predict the time spectrum of the large-volume detector Monte Carlo simulations have been performed. These simulations aimed at anticipating the separation of statistical neutrons, prompt gamma rays and uncorrelated gamma rays from the fast neutrons emitted in the reaction of interest. One of the neutron detectors was tested using fast neutrons from the 232 Th(α,xn) reaction at 42 MeV .