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arXiv · 2010.02945

An Optimization Principle for Computing Stationary MHD Equilibria With Solar Wind Flow

Thomas Wiegelmann·Thomas Neukirch·Dieter H. Nickeler·Iulia Chifu
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Abstract

In this work we describe a numerical optimization method for computing stationary MHD-equilibria. The newly developed code is based on a nonlinear force-free optimization principle. We apply our code to model the solar corona using synoptic vector magnetograms as boundary condition. Below about two solar radii the plasma $\beta$ and Alfv\'en Mach number $M_A$ are small and the magnetic field configuration of stationary MHD is basically identical to a nonlinear force-free field, whereas higher up in the corona (where $\beta$ and $M_A$ are above unity) plasma and flow effects become important and stationary MHD and force-free configuration deviate significantly. The new method allows the reconstruction of the coronal magnetic field further outwards than with potential field, nonlinear force-free or magneto-static models. This way the model might help to provide the magnetic connectivity for joint observations of remote sensing and in-situ instruments on Solar Orbiter and Parker Solar Probe.

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Thomas Wiegelmann, Thomas Neukirch, Dieter H. Nickeler, Iulia Chifu. 2020-10-06. An Optimization Principle for Computing Stationary MHD Equilibria With Solar Wind Flow. https://doi.org/10.1007/s11207-020-01719-8

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