A radial ion diode for generating intense focused proton beams

摘要

A magnetically insulated light ion diode which has produced an ion beam with total current exceeding 400 kA for 25 ns and generated a proton current density approaching 500 kA/cm2 is described. This intense beam current is achieved in a noncurrent neutralized mode via geometric focusing and a balance between self‐magnetic field and space‐charge forces. A number of techniques are described which have been used to diagnose the beam production, transport, and focusing. These include observation of Kα emission due to beam‐induced atomic excitation, prompt‐γ radiation due to beam‐induced nuclear reactions, and thermal emission due to beam‐target heating.