Heating of the magnetically closed corona

J. A. KLIMCHUK; M. C. LÓPEZ FUENTES; C. R. DE VORE

ESA Publications

European Space Agency

Año: 2006 vol. 617 p. 1 - 7

0379-6566

Mounting evidence suggests that much of the corona is heated impulsively on a sub-resolution scale and that the heating is due to the secondary instability of electric current sheets that exist between tangled magnetic strands. We present some preliminary new results that support this view. We suggest that the relative intensities of soft X-ray and EUV emission from active regions (as observed by Yohkoh and EIT or TRACE, for example) are better explained by impulsive heating than by steady heating. We also suggest that the rise, main, and decay phases of loops observed by the Soft X-ray Imager on GOES-12 may be related to the development, maintenance, and destruction of self-organized critical systems. We present an improved ``0D´´ model of dynamic loops that provides an excellent approximation to full solutions of the time-dependent 1D hydrodynamic equations, but using only 10^-4 of the computational resources.