The Details of Coronal Heating Matter!

Abstract:

Understanding how the magnetically-closed corona is heated remains one of the most important goals in Heliophysics. It is generally believed that much or most of the heating involves the conversion of energy that is stored in stressed magnetic fields. What makes the problem so challenging is that the conversion process involves very small spatial scales. Simulations of, e.g., solar active regions cannot resolve the thin current sheets that separate the approximately 100,000 elemental magnetic flux strands that comprise a real active region. Heating in the simulations primarily takes the form of Ohmic dissipation of currents that are far less structured. Thus, the heating is only a proxy for the real heating mechanism. How good a proxy is it? Does it have the essential properties of the real mechanism? We suggest that the details of coronal heating matter. They determine not only the temporal behavior and spatial distribution of the heating, but also the total amount of energy release. We present some idealized MHD simulations that demonstrate this last point.