[en] The structure of the magnetic field of the plane pinch current sheet (CS) was experimentally investigated. The current distributions in different cross sections of the CS were obtained. The structure of the current region was found to be rather complicated, and essentially changed in the course of the CS evolution. (author). 4 refs.; 9 figs

[en] The evolutionary coincidence between the occurrence of the LDE flares and the formation of the evolving delta configuration, in the certain active region, was found. 51 cases of LDE flares have been analysed from the viewpoint of the precise location of their flare loop arcade (located above delta configuration). The quasi delta configurations (i.e. kinematical joining of the two stable spots of the opposite magnetic induction) are not LDE flare productive. (author). 27 refs.; 2 tabs

[en] We discuss our present understanding of magnetotail reconnection leading to plasmoid formation and ejection. We emphasize three-dimensional structures and deviations form earlier imposed symmetries, based on MHD simulations and topological considerations. We find that, in general, the separation of the plasmoid will take a finite amount of time. During this stage the plasmoid is characterized by filamentary structures of interwoven flux tubes with different topological connections. (author). 12 refs.; 7 figs

[en] An experimental study is made of the evolution of a magnetic type-X structure which is produced on a theta-pinch device. It is found that during the initial stage the reconnection process is proceeding in a spontaneous fashion, with periodic restructurings of the current sheet and abrupt accelerations of ions. In the subsequent stage it is stationary in character, with the reconnection rate being in agreement with estimates obtained in terms of the forced reconnection Sweet-Parker model. (author). 11 refs.; 6 figs

[en] The rate of reconnection in the geomagnetic tail presents a quantitative problem. If this rate is to be accounted for by noise, strong turbulence is required. Here noise is neglected and simple discussions of particle motion, velocity distributions and stresses suggest an alternative solution. Electron trajectories are Speiser type and 'residence time' is the crucial quantity. Velocity distributions are skewed, exhibiting electron viscosity. It now seems appropriate to attempt two fluid modelling with anisotropic pressure. The quantitative problem of the tail needs a small spatial scale for the fiels and the tearing mode may be a means to this end. (author). 8 refs.; 1 fig

[en] Two recent families of reconnection models are considered, one for a compressible and one for an incompressible plasma and examine the differences between them. The effects of including compressibility are: . to enhance convergence of divergence of the inflow . to increase the reconnection rate for slow-mode and hybrid compression regimes - to increase the flow speed near the diffusion region for the flux pile-up regimes - to produce outflow jets which are faster, narrower and have magnetic field lines with a smaller curvature. (author). 6 refs.; 3 figs

[en] An incompressible MHD simulation is used to verify the proposed multiple X line reconnection process at the dayside magnetosphere. The 2-d simulation results are briefly reviewed and the preliminary 3-d simulation results are reported. The condition for the occurrence and the dynamical property of the multiple X line reconnection are discussed. The 3-d topology of the reconnected flux tubes is discussed with special attention directed to the ends of the tubes. (author). 8 refs.; 6 figs

[en] Using Potsdam vector magnetograms and a force-free model, we have investigated the magnetic field structure of the active region BBR 18474 of 1982 July 15, and 1982 July 16. By comparison of the azimuths of the current-free model of the magnetic field structure in the central part of this active region with the map of the azimuth values estimated from the observation we find a good qualitative agreement. Additional earlier results have show, that the appearence of highly sheared magnetic field structure near the neutral line in the central part of this active region may be a simulated effect generated by a subphotospheric current system. (author). 6 refs

[en] In taillike configurations magnetic reconnection necessarily leads to the formation of plasmoids. This paper analyses the dynamical evolution of the developing plasmoids and the influence of magnetic reconnection on the propertie of plasmoids. By two dimensional resistive MHD calculations it is shown that plasmoid properties depend very much on the reconnection process especially when the reconnection rate is large. Thus the early plasmoid formation is dominated by magnetic reconnection. At later times the main plasmoid acceleration is due to pressure forces while the tension of open interplanetary fieldlines is negligible. The comparison of different resistivity and equilibrium modells reveals a definite influence of the microscopic dissipation and the initial state on magnetic reconnection and the resulting evolution of plasmoids. (author). 8 refs.; 6 figs

[en] These volume proceedings on reconnection in space plasmas contain 55 contributions which are all in INIS scope. They are subdivides into the following categories: General theory of reconnection, solar reconnection, laboratory reconnection, reconnection at and in magnetospheres and strophysical reconnection. (author). refs.; figs.; tab