Finite deformation in ideal magnetohydrodynamics

Aims. In this paper we investigate the finite deformation of magnetic fields that can enable one to find complex analytical magnetohydrostatic (MHS) equilibria. These can be used as input to non-linear simulations. Methods. In order to find analytical equilibria, one normally has to consider simplifications or exploit a particular symmetry. Even with these measures, however, the desired equilibrium is often out of analytical reach. Here we describe a method that can work when traditional methods fail. It is based on the smooth deformation of simple magnetic fields into complex ones. Results. Examples are given, to demonstrate the method, that are of practical importance in coronal physics. This technique will prove useful in setting up the initial conditions of non-linear magnetohydrodynamic simulations. © 2012 ESO.