Fusion–fission–fusion fast ignition plasma focus

Abstract

A crucial advancement in the problem for the controlled release of energy by nuclear fusion appears possible by an autocatalytic fusion–fission–fusion microexplosion, where the deuterium–tritium (DT) fusion reaction of a dense magnetized DT plasma placed inside a thin liner made up of U238, Th232 (perhaps B10) releases a sufficient number of 14 MeV fusion neutrons which by fission reactions in the liner implode the liner on the DT plasma. The liner implosion increases the DT plasma density and with it the neutron output accelerating the fast fission reactions. Following the fast fission assisted ignition, a thermonuclear detonation wave can propagate into unburnt DT to reach a high gain. The simplest way for the realization of this concept appears to be the dense plasma focus configuration, amended with a nested high voltage magnetically insulated transmission line for the heating of the DT. The large magnetic field needed for the α-particle entrapment of the DT fusion reaction is here generated by the thermomagnetic Nernst effect, amplifying the magnetic field of the plasma focus current sheet.