CHARACTERIZATION OF ELECTRON BEAMS GENERATED IN A HIGH-VOLTAGE PULSE-LINE-DRIVEN PSEUDOSPARK DISCHARGE

Emittance and energy measurements have been performed on a high‐brightness electron beam (≳1010 A/m2 rad2) with diameter in the range 1–3 mm and energy in the range 150–170 keV. This electron beam is generated by the mating of a hollow‐cathode discharge device operating in the pseudospark regime to the output of a high‐power pulse line accelerator. The measured effective emittance lies in the range between 30 and 90 mm mrad and increases with axial distance. Electron energy measurements indicate that the high‐energy electrons are generated during the first 20–30 ns of the discharge. Both the emittance and energy experiments were performed at two different ambient argon gas pressures (92 and 152 mtorr). Beam expansion as a function of axial position has also been studied and a lower bound on the beam brightness has been obtained.