Abstract: Intense soft X-ray source having an enclosure filled with gas and having two electrodes connected to a high voltage source, one of the electrodes having an opening. A device is provided for producing a photoionizing radiation directed through the opening. The radiation traversing the gas in the direction of the other electrode and during its passage producing a plasma microchannel, an electrical discharge supplied by the source then occurring in the microchannel, wherein the device for producing the photoionizing radiation is an auxiliary soft X-ray source.

Abstract: Intense soft X-ray source comprising a means for producing a cylindrical plasma jet between a cathode and an anode, connected to a pulsed high voltage generator, wherein the means for producing the plasma jet comprisesa capacitor bank connected to a charging voltage source and also to a transmission line provided with a tripping means, the assembly having a very low inductance so as to permit a rapid discharge;a sheet of solid material connected by its periphery to one of the conductors of the line and by its central part to the other conductor, so that a radial discharge can be produced when the tripping means is conductive, a plasma jet resulting from the explosion of the sheet;a means for giving the said plasma jet a cylindrical shape.