Dielectric guide controlled collective ion acceleration

Relativistic electron beams with v/γ ≃ 1 have been propagated in a hard vacuum without external magnetic fields through cavities lined with dielectric materials(1). Charge neutralization was provided by ions removed from the surface of the dielectric liner by intense radiation bombardment. Protons were accelerated to energies 2 to 10 times the peak electron energy (70-100 keV). Ion energy increased with the cavity length. Ion velocity scaled directly as the injected current density. A model of the acceleration mechanism, correlating ion velocity with that of the electron beam front, will be presented. Subsequently, this work was scaled to higher energies (2).