Generation and Diagnosis of Terawatt/Centimeter2Electron Beams

Relativistic electron-beam current densities as high as 2.7 MA/${\mathrm{cm}}^2$ and power fluxes of 1.87 TW/${\mathrm{cm}}^2$ have been generated and diagnosed on a pulsed electron-beam accelerator. The beam was field emitted from a 2-mm-diam glass cathode toward a transmission anode. Current densities were inferred by passing the beam through apertures as small as 1 mm and measuring the transmitted current with a Faraday cup.