|
HINODE OBSERVATIONS OF COHERENT LATERAL MOTION OF PENUMBRAL FILAMENTS DURING A X-CLASS FLARE
|
|
Sanjay Gosain Submitted: 2009-11-04 03:08
The X-3.4 class flare of 13 December 2006 was observed with a high cadence of 2 minutes at 0.2
arc-sec resolution by HINODE/SOT FG instrument. The flare ribbons could be seen in G-band
images also. A careful analysis of these observations after proper registration of images show flare
related changes in penumbral filaments of the associated sunspot, for the first time. The observations
of sunspot deformation, decay of penumbral area and changes in magnetic flux during large flares
have been reported earlier in the literature. In this Letter, we report lateral motion of the penumbral
filaments in a sheared region of the -sunspot during the X-class flare. Such shifts have not been seen
earlier. The lateral motion occurs in two phases, (i) motion before the flare ribbons move across the
penumbral filaments and (ii) motion afterwards. The former motion is directed away from expanding
flare ribbons and lasts for about four minutes. The latter motion is directed in the opposite direction
and lasts for more than forty minutes. Further, we locate a patch in adjacent opposite polarity spot
moving in opposite direction to the penumbral filaments. Together these patches represent conjugate
foot-points on either side of the polarity inversion line (PIL), moving towards each other. This
converging motion could be interpreted as shrinkage of field lines.
Authors: S. Gosain, P. Venkatakrishnan and Sanjiv Kumar Tiwari
Projects: Hinode/SOT
|
Publication Status: Accepted in ApJ Letters
Last Modified: 2009-11-04 08:42
|
 
 
 
 
|
|