Use of pulsed bremsstrahlung excitation on hermes-iii for investigation of active detection of fissionable material

We investigate the use of pulsed bremsstrahlung as a standoff active interrogation tool for the production of neutron and gamma signatures in fissionable materials.¹ Photons are generated by an electron beam striking a Ta converter on the 16 MV Hermes III facility at Sandia National Laboratories, and propagate to a target location 19 m from the electron beam diode, at which various materials are placed. X-rays produce (γ,f) and (γ,n) reactions in fissionable material, while nonfissionable materials such as Pb will result in competing (γ,n) reactions. The intense prompt 30 ns x-ray burst from the diode produces γ-rays and neutrons from materials in the environment, all of which must be discriminated by a successful detector set.