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We provide a valid magnetohydrostatic equilibrium from the collapse of a 2DX-point in the presence of a finite plasma pressure, in which the currentdensity is not simply concentrated in an infinitesimally thin, one-dimensionalcurrent sheet, as found in force-free solutions. In particular, we wish todetermine if a finite pressure current sheet will still involve a singularcurrent, and if so, what is the nature of the singularity. We use a full MHDcode, with the resistivity set to zero, so that reconnection is not allowed, torun a series of experiments in which an X-point is perturbed and then isallowed to relax towards an equilibrium, via real, viscous damping forces.Changes to the magnitude of the perturbation and the initial plasma pressureare investigated systematically. The final state found in our experiments is a"quasi-static" equilibrium where the viscous relaxation has completely ended,but the peak current density at the null increases very slowly following anasymptotic regime towards an infinite time singularity. Using a high gridresolution allows us to resolve the current structures in this state both inwidth and length. In comparison with the well known pressureless studies, thesystem does not evolve towards a thin current sheet, but concentrates thecurrent at the null and the separatrices. The growth rate of the singularity isfound to be tD, with 0 < D < 1. This rate depends directly on the initialplasma pressure, and decreases as the pressure is increased. At the end of ourstudy, we present an analytical description of the system in a quasi-staticnon-singular equilibrium at a given time, in which a finite thick current layerhas formed at the null.

Magnetohydrodynamics dynamical relaxation of coronal magnetic fields. II. 2D magnetic X-points