The pseudospark as an electron beam source

The pseudospark is a low-pressure, hollow-cathode gas discharge that occurs in a special discharge geometry (pseudospark chamber) in different kinds of gases. A modular pseudospark chamber was built to investigate this discharge type as a source of intense electron beams. At a breakdown voltage of 24 kV and a discharge current of 480 A, an electron beam of 106 A and 13 ns FWHM (full width at half maximum) was extracted through the anode hole into a drift chamber filled with low-pressure gas. Electrical parameters of the circuit, including the plasma channel, were evaluated by monitoring the discharge current waveform. First results of beam profile and emittance measurements of the produced electron beam are presented. At an axial distance of 9 cm behind the anode, an RMS emittance of 55 mm-mrad was measured. The results obtained make it possible to consider the pseudospark discharge a high-brightness electron beam source.<
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