The Spatial and Temporal Dependence of Coronal Heating by Alfven Wave Turbulence

TL;DR

This paper investigates how Alfven wave turbulence contributes to coronal heating by simulating wave dynamics in observed active region loops, providing a formula for average heating rates applicable to 3D solar corona models.

Contribution

It introduces a 3D MHD simulation approach to quantify Alfven wave heating in active regions and derives a general formula for the heating rate applicable to other regions.

Findings

Derived an average heating rate formula as a function of position.

Simulated wave dynamics in observed coronal loops.

Proposed a method for constructing 3D time-dependent coronal models.

Abstract

The solar atmosphere may be heated by Alfven waves that propagate up from the convection zone and dissipate their energy in the chromosphere and corona. To further test this theory, we consider wave heating in an active region observed on 2012 March 7. A potential field model of the region is constructed, and 22 field lines representing observed coronal loops are traced through the model. Using a three-dimensional (3D) reduced magneto-hydrodynamics (MHD) code, we simulate the dynamics of Alfven waves in and near the observed loops. The results for different loops are combined into a single formula describing the average heating rate Q as function of position within the observed active region. We suggest this expression may be approximately valid also for other active regions, and therefore may be used to construct 3D, time-dependent models of the coronal plasma. Such models are needed to understand the role of thermal non-equilibrium in the structuring and dynamics of the Sun's corona.