Update on a ZnO:Ga Alpha Particle Detector for a Portable Neutron Generator for the Nuclear Materials Identification System (NMIS)

Year
2006
Author(s)
John T. Mihalczo - Oak Ridge National Laboratory
J.T. Mihalczo - Oak Ridge National Laboratory
Paul A. Hausladen - OAK RIDGE NATIONAL LABORATORY
John S. Neal - Oak Ridge National Laboratory
John S. Neal - Oak Ridge National Laboratory
David Koltick - Purdue University Physics Department and Applied Physics Laboratory
Charles Cooper - Purdue University Physics Department and Applied Physics Laboratory
Abstract
An associated particle sealed tube neutron generator (APSTNG) is currently used as an interrogation source for the Nuclear Materials Identification System (NMIS). With the emission of 14 MeV neutrons produced by the D-T reaction, associated 3.5 MeV alpha particles are emitted. These neutrons and alpha particles may then be correlated in time and position, thus effectively “tagging” the neutrons of interest for subsequent use as an active nuclear materials interrogation source. The alpha particle detector uses a ZnO:Ga scintillator coating applied to a fiber optic face plate. Previous measurements used small sample sizes for coating thickness optimization studies and a full size prototype fiber optic face plate. A ZnO:Ga alpha detector has now been installed in an APSTNG and tested. We report our most recent measurement results and discuss the design of our next-generation alpha detector.