A Self-consistent Model for the Resonant Heating of Coronal Loops: the Effects of Coupling with the Chromosphere

We present the Ðrst model of resonant heating of coronal loops that incorporates the dependence of the loop density on the heating rate. By adopting the quasi-static equilibrium scaling law o P Q5@7, where o is the density and Q is the volumetric heating rate, we are able to approximate the well-known phenomena of chromospheric evaporation and chromospheric condensation, which regulate the coronal density. We combine this scaling law with a quasi-nonlinear MHD model for the resonant absorption of Alfve n waves in order to study the spatial and temporal dependence of the heating. We Ðnd that the heating is concentrated in multiple resonance layers, rather than in the single layer of previous models, and that these layers drift throughout the loop to heat the entire volume. These newfound properties are in much better agreement with coronal observations. Subject headings : MHD È Sun: chromosphere È Sun: corona È Sun: magnetic Ðelds È waves