Evolution of self-organised space charge structure in plasma related to the current-voltage characteristics

The genesis of well localized space charge structure in a plasma after application of an external constraint sustained by a positively biased electrode that produce a local electron acceleration was investigated. Plotting the current vs voltage characteristic we first observed the generation of a nearly spherical luminous well definite space charge structure formed in the next vicinity of the electrode surface. By increasing the electrode voltage from this nearly spherical formation a second well defined luminous space charge structure is shelling off, appearing in the form of a striation. For a certain value of the electrode voltage the dynamically current-voltage characteristics evidences the presence of periodical phenomena produced by a successively generation, motion and disruption of striation springing from the initially formed nearly space charge formation. The generation and evolution of the appeared space charge structures can by related with the different branches of the static and dynamical current-voltage characteristics whose aspect reveals all the essential behaviour proper to typical self-organisation phenomena (anomalous resistance bistability, hysteresis, route-to-chaos by-intermittent oscillations, and others). (Author)