High Rfsolution Fast Neutron Spectrometry without Time-of-Flight

Abstract

Performance tests of a spectrometer tube of the type developed by Cuttler and Shalev show that the measurement of fast neutron spectra with this device can be made with an energy resolution previously obtainable only in large time-of-flight facilities. In preliminary tests, resolutions of 16.4 keV for thermal neutrons and 30.9 keV for 1-MeV neutrons were obtained. A broad-window pulse-shape discrimination (PSD) system is used to remove fram pulse-height distributions most of the continua due to 3He-recoil events, noise, and wall effect. Use of PSD improved the energy resolution to 12.9 keV for thermal neutrons and 29.2 keV for l-MeV neutrons. The detector is a viable tool for neutron research at nominally equipped accelerator laboratories.