A comparative study of n-γ discrimination and uniformity of long liquid scintillation detectors

Liquid organic scintillators used for neutron spectrometry must be employed with pulse shape discrimination against gamma radiation. As the dimensions of the spectrometer are increased, the uniformity and the n-γ discrimination properties of the spectrometer deteriorate while its efficiency increases. The properties of a NE-213 liquid scintillator of a parallelepiped shape are investigated with respect to the spectrometer length. For the geometry of a point source near the spectrometer wall, it is estimated that a spectrometer of a length of 10-15 cm will display optimal performance. (orig.)