VUV emission from high-intensity focused REB discharges into aluminum targets

The VUV emission from 6061-T6 aluminum targets, exposed to an intense focused electron beam, was examined to study the electron absorption mechanism for a 1-MeV electron beam with a current density of 1 MA/cm2. The VUV emission was observed with aluminum cathode x-ray diodes operated with and without 1/2-μm aluminum filters and a near-normal incidence grating spectrograph. The data obtained are consistent with classical electron deposition and indicate an anode surface temperature of a few eV with the peak temperature occurring at the time of impedance collapse.