Calibration and use of a 5-inch diameter lithium glass detector

Abstract A 5 in-diam. by 0.5 in-thick lithium glass scintillator has been calibrated from 50 eV to 8 MeV neutron energy using the 10 B(n,α) and H(n,p) cross sections as standards. Monte Carlo calculations of the detector efficiency have been made and found to agree with observed values below 250 keV and to disagree above that energy. The scintillator efficiency has been found to increase at energies above 1 MeV due to detection of gamma rays from inelastic neutron scattering. The detector has been used to measure neutron spectra at intermediate energies by the time-of-flight technique. A systematic method is presented for removing background gamma rays that does not require the use of a depleted lithium glass scintillator or the use of pulse shape discrimination.