Proposal for a High-lntensity 14-MeV Cutoff Neutron Source Based on the ¹H(t,n)¹He Source Reaction

A high-intensity, high-energy neutron source for fusion materials testing is proposed. Utilizing the ¹H(t,n)³He neutron source reaction and bombarding a thick (totally absorbing) hydrogen-rich target with an intense beam of 21-MeV tritons provides a powerful continuous-energy-spectrum neutron source. The global spectrum of such a source is almost flat over the energy range from ∼1 to 14 MeV and exhibits a sharp energy cutoff level at 14.6 MeV. To meet near-term needs for fusion materials testing, a source concept is considered that involves multiple linear accelerator modules providing two 250-mA triton beams to bombard two water jet targets that face each other and irradiate the same test volume. Calculations of the source properties from well-established neutron production cross-section data for the ¹H(t,n)³He reaction predict a test volume of 4.2 dm³ in which an average flux of ≥1 × 10¹⁴ n·cm^-2·s^-1 is achieved. The relevant properties of this source and the possibility of its realization, well within the limits of present technology, are discussed.