Features of fast deuterons emitted from plasma focus discharges

This paper presents the discussion concerning the characteristics of the fast deuterons which have energy above 30 keV and are recorded during high-current plasma-focus (PF) discharges, by means of PM-355 plastic track-detectors placed inside ion pinhole cameras. The fast deuterons evoke D-D fusion reactions, mainly by a beam-target mechanism. 'fhe distribution of the magnetic field, which influences the trajectories of the recorded deuterons, is discussed. It is found that the fast deuterons are produced in various local sources and their motion is strongly influenced by a circular symmetry of the local magnetic field, which increases their radial shift with a decrease in their energy. The sources of these deuterons are probably located inside the plasmoids and in some local regions of the ring-shaped plasma structures. These ring-structures can he formed outside the dense pinch column, up to a radius of 5 cm. Global magnetic fields, associated with the total current flow in the PP discharge, have a weaker influence. The observed radial shift of the recorded fast deuterons is interpreted as a result of their deflection by magnetic fields which have opposite orientations of the azimuthal components, associated with the currents flowing in directions towards and from the applied ion detectors. The local sources of the recorded fast deuterons correspond to filamentary structures, in which the stored magnetic energy (having the local high density) can he released in induced electric fields accelerating the deuterons during the magnetic reconnections. Published under license by ATP Publishing.