Previous abstract Next abstract

Session 16 - Magnetic Fields I.
Oral session, Tuesday, July 01
Ballroom A, Chair: Edward DeLuca

[16.02] Currents, Magnetic Fields and Heating in a Solar Active Region

J. Lee (U.Md.), A. N. McClymont (U. Hawaii), Z. Miki\'c (SAIC), S. M. White, M. R. Kundu (U.Md.)

We have compared high-quality microwave images of the radio emission from the corona above an active region with state-of-the-art nonlinear force-free extrapolations of the photospheric magnetic field. The radio images, which are dominated by the opacity provided by the coronal magnetic fields, show excess magnetic field in locations consistent with the expected location of coronal currents. We test the hypothesis that the degree of heating on a given coronal magnetic flux tube is related to the current flowing through it by comparing model radio brightness distributions at different frequencies with the actual observations. In the model we assume that temperature is distributed along the field lines according to quasi-static loop models, and that there is effectively no diffusion across the field lines. This coronal heating model is able to reproduce the radio brightness distributions remarkably well.


The author(s) of this abstract have provided an email address for comments about the abstract: leejw@astro.umd.edu

Program listing for Tuesday