Elena Khomenko, Manuel Collados
In this paper, we study the heating of the magnetized solar chromosphere
induced by the large fraction of neutral atoms present in this layer. The
presence of neutrals, together with the decrease with height of the collisional
coupling, leads to deviations from the classical MHD behavior of the
chromospheric plasma. A relative net motion appears between the neutral and
ionized components, usually referred to as ambipolar diffusion. The dissipation
of currents in the chromosphere is enhanced orders of magnitude due to the
action of ambipolar diffusion, as compared to the standard ohmic diffusion. We
propose that a significant amount of magnetic energy can be released to the
chromosphere just by existing force-free 10--40 G magnetic fields there. As a
consequence, we conclude that ambipolar diffusion is an important process that
should be included in chromospheric heating models, as it has the potential to
rapidly heat the chromosphere. We perform analytical estimations and numerical
simulations to prove this idea.
View original:
http://arxiv.org/abs/1112.3374
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