title: Secondary instabilities and vortex formation in collisionless-fluid magnetic reconnection.
abstract: It is shown that the pattern of current layers formed within a magnetic island in the nonlinear phase of magnetic field line reconnection in a collisionless two-dimensional fluid plasma is subject to the onset of a secondary instability, the effect of which increases with decreasing electron temperature. In the cold electron limit the saturation of the island growth is accompanied by a turbulent redistribution of the current layers and by the development of long lived fluid vortices while, in the opposite limit, the current layer structure remains regular.
authors.affiliation: Physics Department, University of Pisa and INFM, Pisa, Italy.
authors.forename: D
authors.initials: D
authors.lastname: Del Sarto
authors.forename: F
authors.initials: F
authors.lastname: Califano
authors.forename: F
authors.initials: F
authors.lastname: Pegoraro