A 14-MeV beam-plasma neutron source for materials testing

The design and performance of 14-MeV beam-plasma neutron sources for accelerated testing of fusion reactor materials are described. Continuous production of 14-MeV neutron fluxes in the range of 5 to 10 MW/m² at the plasma surface are produced by D-T reactions in a two-component plasma. In the current designs, 14-MeV neutrons result from collisions of energetic deuterium ions created by transverse injection to 150-keV deuterium atoms on a fully ionized tritium target plasma. The beam energy, which is deposited at the center of the tritium column, is transferred to the warm plasma by electron drag, which flows axially to the end regions. Neutral gas at high pressure absorbs the energy in the tritium plasma and transfers the heat to the walls of the vacuum vessel. The plasma parameters of the neutron source (in dimensionless units), have been achieved in the 2XIIB high-β plasma. The larger magnetic field of the present design permits scaling to the higher energy and density of the neutron-source design