USE OF NUCLEAR MATERIALS IDENTIFICATION SYSTEM’S (NMIS) HIGHER ORDER SIGNATURES (HOS) TO ANALYZE DETECTOR INTERACTIONS

Year
2001
Author(s)
John T. Mihalczo - Oak Ridge National Laboratory
John K. Mattingly - Oak Ridge National Laboratory
J.A. Mullens - Oak Ridge National Laboratory
L.G. Chiang - Oak Ridge National Laboratory
R.B. Oberer - Oak Ridge National Laboratory
Sara A. Pozzi - Department of Nuclear Engineering
Abstract
Cross talk occurs when a particle that is detected in a detector is subsequently detected in a neighboring detector. In this paper a method is proposed to infer the degree and type of neutron and gamma ray cross talk between detectors that are placed side by sid e. To this end, a set of measurements was performed using the Nuclear Materials Identification System (NMIS) to acquire the time-dependent bicovariance functions of the pulses registered by an instrumented 252Cf source and two fast plastic scintillators. The acquired signatures were then analyzed to infer the degree and type of coincidences due to cross talk in relation to “true” coincidences given by the spontaneous fission process. PACS: 29.90.+r, 29.40.Mc, 28.20.Cz Key words: higher order statistics; correlation measurements; cross talk; plastic scintillators; neutron detection; nuclear safeguards