Test magnetohydrostatic extrapolation with radiative MHD simulation of a solar flare

TL;DR

This paper tests a magnetohydrostatic extrapolation model against a radiative MHD simulation of a solar flare, demonstrating improved magnetic field and plasma structure modeling in the solar atmosphere.

Contribution

It presents a realistic test of the MHS extrapolation model using a radiative MHD simulation, showing enhanced accuracy over NLFFF in modeling the solar atmosphere.

Findings

MHS model improves magnetic field magnitude and direction.

MHS model recovers main plasma structures in photosphere and chromosphere.

Enhanced magnetic connectivity modeling.

Abstract

Context. On the sun, the magnetic field vector is measured routinely only in the photosphere. By using these photospheric measurements as boundary condition, we developed the magnetohydrostatic (MHS) extrapolation to model the solar atmosphere. The model makes assumption about the relative importance of magnetic and non-magnetic forces. While the solar corona is force-free, this is not the case in photosphere and chromosphere. Aim. The model has been tested with an exact equilibria in \cite{zw18}. Here we present a more challenging and realistic test of our model with radiative MHD simulation of a solar flare. Methods. By using the optimization method, the MHS model computes self-consistently the magnetic field, plasma pressure and density. The nonlinear force-free field (NLFFF) and gravity stratified atmosphere along the field line are assumed as the initial condition of the optimization. Results. Compared with NLFFF, the MHS model gives an improved magnetic field not only in magnitude and direction, but also in the magnetic connectivity. Besides, the MHS model is able to recover the main structure of the plasma in the photosphere and chromosphere.