Two Dimensional Models Of The Coronal Magnetic Field

The large scale magnetic field in the solar corona is assumed to be a superposition of small-scale fields resulting from the supergranule currents located near the chromospheric- coronal boundary and obeying specified statistics together with a dipole field related to the processes deeper within the sun. Our analysis of the resulting magnetic field patterns reveals that they critically depend on the number of current jets associated with the supergranules. This dependence is found to be qualitatively similar to the observed variations of the coronal field with solar activity. A second model is employed to simulate the fine structure of the field within particular supergranule: here a plane current-currying layer approximation is used with an externally- specified large-scale magnetic field as fitting parameter. The escape of energetic particles from the chromospheric — coronal boundary is studied as an application of the models.