Solar Physics

, Volume 258, Issue 2, pp 203–217 | Cite as

The Rotating Sunspot in AR 10930

  • Soonyoung Min
  • Jongchul Chae


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.


Sunspots, magnetic fields Magnetic fields, photosphere Magnetic fields, corona 


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  1. Brown, D.S., Nightingale, R.W., Alexander, D., Schrijver, C.J., Metcalf, T.R., Shine, R.A., Title, A.M., Wolfson, C.J.: 2002, In: Sawaya-Lacoste, H. (ed.) SOLMAG 2002. Proceedings of the Magnetic Coupling of the Solar Atmosphere Euroconference SP-505, ESA, Noordwijk, 261. Google Scholar
  2. Brown, D.S., Nightingale, R.W., Alexander, D., Schrijver, C.J., Metcalf, T.R., Shine, R.A., Title, A.M., Wolfson, C.J.: 2003, Solar Phys. 216, 79. CrossRefADSGoogle Scholar
  3. Chae, J., Sakurai, T.: 2008, Astrophys. J. 689, 593. CrossRefADSGoogle Scholar
  4. Chae, J., Wang, H., Qiu, J., Goode, P.R., Strous, L., Yun, H.S.: 2001, Astrophys. J. 560, 476. CrossRefADSGoogle Scholar
  5. Chae, J., Moon, Y.-J., Rust, D.M., Wang, H., Goode, P.R.: 2003, J. Korean Astron. Soc. 36, 33. ADSGoogle Scholar
  6. Ding, Y.J., Hong, Q.F., Wang, H.Z.: 1987, Solar Phys. 107, 221. CrossRefADSGoogle Scholar
  7. Knoska, S.: 1975, Astron. Inst. Czechoslov. 26, 151. ADSGoogle Scholar
  8. Longcope, D.W., Welsch, B.T.: 2000, Astrophys. J. 545, 1089. CrossRefADSGoogle Scholar
  9. Magara, T., Tsuneta, S.: 2008, Publ. Astron. Soc. Japan 60, 1181. ADSGoogle Scholar
  10. Molowny-Horas, R.: 1994, Solar Phys. 154, 29. CrossRefADSGoogle Scholar
  11. Parker, E.N.: 1974, Astrophys. J. 191, 245. CrossRefADSGoogle Scholar
  12. Schrijver, C.J., Elmore, C., Kliem, B., Törok, T., Title, A.M.: 2008, Astrophys. J. 674, 586. CrossRefADSGoogle Scholar
  13. Su, Y., Golub, L., van Ballegooijen, A., Deluca, E.E., Reeves, K.K., Sakao, T., Kano, R., Narukage, N., Shibasaki, A.: 2007, Publ. Astron. Soc. Japan 59, S785. ADSGoogle Scholar
  14. Tian, L., Alexander, D.: 2006, Solar Phys. 233, 29. CrossRefADSGoogle Scholar
  15. Tian, L., Alexander, D., Nightingale, R.: 2008, Astrophys. J. 684, 747. CrossRefADSGoogle Scholar
  16. Wang, H., Jing, J., Tan, C., Wiegelmann, T., Kubo, M.: 2008, Astrophys. J. 687, 658. CrossRefADSGoogle Scholar
  17. Yan, X.L., Qu, Z.Q.: 2007, Astron. Astrophys. 468, 1083. CrossRefADSGoogle Scholar
  18. Zhang, J., Li, L., Song, Q.: 2007, Astrophys. J. 662, L35. CrossRefADSGoogle Scholar
  19. Zhang, Y., Liu, J., Zhang, H.: 2008, Solar Phys. 247, 39. CrossRefADSGoogle Scholar
  20. Zhang, Y., Tin, B., Yan, Y.: 2008, Astrophys. J. 682, L133. CrossRefADSGoogle Scholar

Copyright information

© Springer Science+Business Media B.V. 2009

Authors and Affiliations

  1. 1.Department of Physics and AstronomySeoul National UniversitySeoulKorea

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