Magnetohydrostatic modelling of stellar coronae

TL;DR

This paper presents a magnetohydrostatic model for stellar coronae that extends potential field models by coupling magnetic fields with the background atmosphere, allowing analytical solutions and investigation of magnetic field topology.

Contribution

It introduces a new MHS modeling approach for stellar coronae, incorporating atmospheric coupling and analytical solutions, with application to an M-dwarf star.

Findings

Model influences magnetic field geometry and topology.

Analytical solutions demonstrate the approach's feasibility.

Application to GJ 182 illustrates the model's practical use.

Abstract

We introduce to the stellar physics community a method of modelling stellar coronae that can be considered to be an extension of the potential field. In this approach, the magnetic field is coupled to the background atmosphere. The model is magnetohydrostatic (MHS) and is a balance between the Lorentz force, the pressure gradient and gravity. Analytical solutions are possible and we consider a particular class of equilibria in this paper. The model contains two free parameters and the effects of these on both the geometry and topology of the coronal magnetic field are investigated. A demonstration of the approach is given using a magnetogram derived from Zeeman-Doppler imaging of the 0.75 M$_{\odot}$ M-dwarf star GJ 182.