SELF-SIMILAR DYNAMICS OF CURRENT COALESCENCE IN A THIN CURRENT SHEET

The dynamics of thin current sheets takes on special importance in stu dying the processes occurring in both laboratory and astrophysical pla smas. In this paper, the dynamics of current filamentation is consider ed using a dynamic model that was first proposed by B. A. Trubnikov in order to study the initiation of pinches in the interaction of magnet ized plasma clouds. It is shown that this dynamic system is Hamiltonia n, and collapse resulting in the formation of individual current filam ents that each carry a finite current inevitably occurs in this system . Self-similar solutions are obtained describing the collapse of an in dividual current filament both in the ''self-compression'' regime and with allowance for the influence of the remaining current filaments.