Neutron Generator and Applications in Nuclear Physics

Full text. Compact neutron generators based on d-d, d-t and t-t fusion reactions have been developed for many nuclear physics applications. For Prompt Gamma Activation Analysis (PGAA) and Neutron Activation Analysis (NAA), both axial and coaxial type d-d generators with the properly designed moderator have been constructed to produce thermal neutrons with flux higher than 107 n/cm2.sec. Recently, a high intensity coaxial d-d neutron source is being developed for 40Ar/39Ar geochronology applications. Both interference corrections and recoil displacements will be significantly reduced by replacing the fission reactor neutrons with the 2.45 MeV d-d neutrons in the 39K(n,p)39Ar capture reaction. In nuclear cross-section measurements and in Pulsed Fast Neutron Transmission Spectroscopy (PFNTS), ultra-short neutron pulses are needed for time-of-flight energy separation. Compact neutron generators equipped with fast gating elements can now produce 5 ns short neutron pulses. For neutron imaging purposes, a new type of neutron generator with source size ∼ 1-mm-diameter has been developed. The source size can be further reduced to submicron dimension for analyzing biological samples. The status and the characteristics of these new generation neutron sources will be presented in this conference. (author)