Physics
Scientific paper
Sep 2009
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2009soph..258..203m&link_type=abstract
Solar Physics, Volume 258, Issue 2, pp.203-217
Physics
14
Sunspots, Magnetic Fields, Magnetic Fields, Photosphere, Magnetic Fields, Corona
Scientific paper
We study the pattern and behavior of a rotating sunspot in Active Region 10930. The rotational angular speed has been extracted from the apparent motions of the sunspot determined by applying a new optical technique - called non-linear affine velocity estimator (NAVE) - to high-resolution G-band images taken by the Solar Optical Telescope (SOT) onboard the Hinode satellite. The structure and dynamics of coronal loops in this active region have been examined using the images obtained by the X-Ray Telescope (XRT) and the spectral data taken by the Extreme-ultraviolet Imaging Spectrometer (EIS), both also onboard Hinode. Our results are summarized as follows: i) The small sunspot of positive polarity rotated counterclockwise about its center by 540° during the period of five days. ii) Its angular velocity varied with the azimuth angle as well as the radial distance, being affected by the asymmetric shape of the umbra. iii) The angular velocity increased up to 8° h-1 until 13 December as the sunspot grew, and then decreased rapidly down to 3° h-1 on the next day as the sunspot decayed. iv) The coronal loops that connected the two sunspots became sigmoidal in shape. v) The coronal emissions from the regions around the rotating sunspot were blueshifted, which may indicate the expansion of the coronal loops. Our results suggest that the rotation of the sunspot may be closely related to the dynamic development of emerging twisted magnetic fields.
Chae Jongchul
Min Soonyoung
No associations
LandOfFree
The Rotating Sunspot in AR 10930 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with The Rotating Sunspot in AR 10930, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Rotating Sunspot in AR 10930 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1074920