Speaker
Description
First Name: Cosima
Last Name: Breu
Email Address: brecosima.breu@uni-graz.at
Affiliation: University of Graz
All Authors: Cosima Breu
Abstract: A large part of the solar -and possibly stellar- corona is made up of closed magnetic loops containing hot and bright plasma. The exact physical mechanism leading to the heating of the plasma is still unclear. Numerous scaling laws have been proposed that relate loop properties such as peak temperature, density, or heating rate to coronal loop length and magnetic field. These scaling laws are valuable tools to constrain the mechanism responsible for coronal heating. This is especially true for stars other than the Sun, where the small-scale structure of the corona cannot directly be observed and the interpretation of observations must rely on scaling laws. These scaling relations for coronal loops are usually derived from analytical or numerical models under simplifying assumptions, such as hydrostatic equilibrium or, in the case of simulations, a prescribed driver injecting energy by tangling the magnetic field. In this study, we investigate how loop length and coronal magnetic field strengths influence the energy injection into coronal loops in models driven self-consistently by magnetoconvection rather than by an imposed driver. We model the coronal loop as a straightened magnetic flux tube in a Cartesian box using the radiative 3D MHD code MURaM. The loop is rooted in a shallow convection zone layer at each footpoint, allowing for a self-consistent coupling between the photosphere, chromosphere, and corona. This setup allows for easily controlling the loop length and magnetic field strength while capturing the energy transport through different atmospheric layers. In this talk, I will review existing relations and compare them with new results for loop simulations spanning from the convection zone into the corona.