Rapid Transition of Uncombed Penumbrae to Faculae during Large Flares
Wang, Haimin, Na Deng, and Chang Liu, Rapid Transition of Uncombed Penumbrae to Faculae during Large Flares, ApJ, 748, 76 (2012) (ADS)
(click on the image for a larger version)
The penumbra of a large sunspot is very different from the ordinary
photosphere, with tilts and gradients of a strong magnetic field.
This cartoon points out how a solar flare can result in major changes to
the field structure.
A previously "uncombed" penumbra can be smoothed out by the distortion of the
magnetic field required
for energy conversion.
Since the photosphere is by definition optically thick, these changes
themselves must play a role in flare energetics.
In addition to this major flare effect,
microscopic hanky-panky may
also be happening.
The penumbra of a large sunspot is very different from the ordinary photosphere, with tilts and gradients of a strong magnetic field. This cartoon points out how a solar flare can result in major changes to the field structure. A previously "uncombed" penumbra can be smoothed out by the distortion of the magnetic field required for energy conversion. Since the photosphere is by definition optically thick, these changes themselves must play a role in flare energetics. In addition to this major flare effect, microscopic hanky-panky may also be happening.