A Model for Coronal Heating with a Photospheric Driver
Thomas Howson
University of St Andrews
Ineke De Moortel (University of St Andrews), Jenny O'Hara (University of St Andrews)
It is widely accepted that the convective driving of the photosphere can generate a Poynting Flux into the solar atmosphere that is sufficient to power coronal heating. A driver that is slow in comparison to the local Alfven speed will build stresses in the atmospheric magnetic field, which can be released during reconnection events. Using the numerical code Lare3D, we present a coronal model that considers the effects of continuous driving on two magnetic flux-tubes. These initially straight tubes are allowed to relax towards a numerical equilibrium before a velocity field is imposed at the loop footpoints. This mimics a rotational driver that braids the flux-tubes around each other. As a result, intricate current sheets are formed, inducing intense but highly localised heating. We include the effects of thermal conduction to determine how this heat is re-distributed and consider the efficiency of heat transfer parallel to the magnetic field. Further, we investigate the magnitude of radiative cooling on the heating timescale in order to help establish the efficacy of the proposed heating mechanism.