A dual-current-feed magnetically insulated light-ion diode

Abstract

A 3×10¹¹‐W modular magnetically insulated ion diode for inertial‐confinement fusion studies is described. Power is supplied to the diode, which is centered in an elongated solenoidal B‐field coil structure, by two self‐magnetically insulated transmission lines. A circular ion beam is emitted preferentially from one surface of the curved anode plate and extracted through a 13‐cm‐diam virtual cathode and exposed B‐field coils. The virtual cathode is formed by electrons which spiral along the B‐field lines that conform to the anode surface. The ion beam converges onto a planar target, located 13‐cm from the anode, through a 1‐Torr air plume which allows space‐charge and partial current neutralization of the beam. The beam is initially primarily composed of protons, but later carbon ions dominate. The proton beam has a divergence of 2.1°±0.3° and peak focused proton‐current density of 60 kA/cm².