Abstract: Negative ion source making it possible to produce an intense beam of negative ions, particularly of hydrogen and deuterium, as well as negative ions of other species. According to the main feature of this negative ion source, the number and distribution of the permanent magnets forming the magnetic multicusp confinement is chosen in such a way that the confinement time of the primary electrons is between 10.sup.-7 and 10.sup.-6 second and the thermionic electron emitters are located in the multicusp magnetic field between the saddle point of the magnetic field, formed by two adjacent permanent magnets and the center of the plasma in the vicinity of said saddle points. It is advantageously applied to the production of high-energy neutral atom beams used e.g. as an effective means for heating plasmas, produced in magnetic confinement fusion means.

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.