UC Berkeley

The development of compact electronic gamma and neutron sources utilizing several deuteron-induced nuclear reactions on low-Z compounds are presented in this study. These systems feature a compact high current density RF inductive discharge plasma source to provide the ion current necessary for a high yield gamma or neutron source. The first part of this project studied an electronic gamma source that utilized low-energy (d,ng) nuclear reactions to generate mono-energetic gamma rays (0.5 to 1.5 MeV) having energies similar to existing radiological sources used in the field (e.g. ⁶⁰Co, ¹³⁷Cs, ¹⁹²Ir). The source incorporates a novel compact pyroelectric crystal powering system that produces the high voltage needed by thermal cycling the crystal in the room temperature range. Experiments were carried out and an analysis was performed to determine the gamma source performance requirements to provide equivalent or improved functionality for the user community, while being less susceptible to malevolent use.

The second part of this project studied the next generation of compact high flux electronic neutron generators that utilized the deuteron-deuteron (D-D) reaction to produce 2.45 MeV neutrons. The maximum flux level for a 120 keV - 1 ampere D⁺ beam bombarding titanium is expected to approach 10¹¹ n*cm^-2*s^-1, which is close to the levels available in research reactors and large accelerator facilities. Analysis and experiments with the neutron generators show promise for utilization in traditional applications that require reactor neutrons such as the ³⁹Ar/⁴⁰Ar geochronology dating technique and boron-neutron-capture therapy (BNCT).