Development of Dense Plasma Foci as Advanced Neutron Sources at LLNL

Abstract

The dense plasma focus (DPF) is a z-pinch device that starts as a coaxial plasma railgun and ends in an implosion phase. DPF's historically were developed as thermonuclear devices. When used with deuterium and tritium gases a DPF can be used to produce neutrons; however, in operation, DPF's often suffered from inconsistent behavior, and the mechanisms driving the neutron production were poorly understood. Using kinetic modeling techniques recently developed at LLNL, we have gained insight into the mechanisms that lead to particle acceleration in the pinch region and can make informed design decisions for optimizing DPF behavior, from sub-kilojoule to mega-joule scale devices. Experimental DPF platforms at LLNL also serve to validate the behaviors seen in simulations and improve device performance with a view towards increased neutron generation, enhanced reproducibility, and decreased size and energy requirements.