Experimental study of pseudospark‐produced electron beams

A brief review on the status of pseudospark research is given. A modular pseudospark chamber was built to investigate this new discharge type as a source of intense electron beams. Typical experimental parameters are a brakedown voltage of 25 kV and a discharge current of about 500 A, with an electron beam of ∼100 A and ∼10 ns FWHM emitted through the anode hole into a drift chamber. Electrical parameters of the circuit, including the plasma channel, were evaluated by monitoring the discharge current waveform. First results of emittance measurements of the electron beam are presented. Based on the measured rms emittance of ∼55 mm‐mrad, a normalized brightness of about 2×1011 A/m2‐rad2 is estimated. This characterizes the pseudospark as a high brightness electron beam source.