Spatial resolution of neutron-position scintillation detectors

An Intense Pulsed Neutron Source (IPNS) was recently built at Argonne. From the point of view of neutron detection a pulsed source has two characteristics which are basically different from those of a steady-state source such as a reactor: broad spectrum of neutron energies in which a greater fraction of the flux is in the epithermal range, and high instantaneous neutron flux. A detector to be used with a pulsed source should therefore have: high neutron detection efficiency extending to epithermal energies, and high instantaneous count-rate capability. In response to these requirements a new neutron position-sensitive detector was developed. The detector is comprised of an array of photomultiplier tubes coupled to a thin 6Li-glass scintillator. The principle of operation is similar to that of the Anger gamma-ray camera used in nuclear medicine