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Solar Physics

, Volume 207, Issue 1, pp 111–123 | Cite as

Active-Region Filaments and X-ray Sigmoids

  • Alexei A. Pevtsov
Article

Abstract

We use Yohkoh soft X-ray telescope data and Hα full-disk observations to study the evolution of chromospheric filaments and coronal sigmoids in 6 active regions in association with coronal mass ejections (CMEs). In two cases, CMEs are directly observed by the SOHO/LASCO C2 coronagraph. In four cases, other observations (magnetic clouds, geomagnetic storms, sigmoid-arcade evolution) are used as CME indicators. Prior to eruption, each active region shows a bright coronal sigmoidal loop and underlying Hα filament. The sigmoid activates, erupts and gets replaced by a cusp, or an arcade. In contrast, the Hα filament shows no significant changes in association with sigmoid eruption and CME. We explain these observations in a framework of the classical two-ribbon flare model.

Keywords

Flare Active Region Coronal Mass Ejection Geomagnetic Storm Magnetic Cloud 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. Aurass, H., Vršnak, B., Hofmann, A., and Rudžjak, V.: 1999, Solar Phys. 190, 267.Google Scholar
  2. Bothmer, V. and Rust, D. M.: 1997, in N. Crooker, J. A. Joselyn, and J. Feynman (eds.), Coronal Mass Ejections, American Geophysical Union, Washington, D.C., p. 139.Google Scholar
  3. Bothmer, V. and Schwenn, R.: 1994, Space Phys. Rev. 70, 215.Google Scholar
  4. Canfield, R., Hudson, H. S., and Pevtsov, A. A.: 2000, IEEE Trans. Plasma Science 28, 1786.Google Scholar
  5. Canfield, R. C., Hudson, H. S., and McKenzie, D. E.: 1999, Geophys. Res. Lett. 26, 627.Google Scholar
  6. Delaboudiniè re, J.-P. et al.: 1995, Solar Phys. 162, 291.Google Scholar
  7. Domingo, V., Fleck, B., and Poland, A. H.: 1995, Solar Phys. 162, 1.Google Scholar
  8. Falconer, D. A.: 2001, J. Geophys. Res. 106, 25185.Google Scholar
  9. Gibson, S. E. and Low, B. C.: 2000, J. Geophys. Res. 105, 18187.Google Scholar
  10. Gilbert, H. R., Holzer, T. E., Low, B. C., and Burkepile, J. T.: 2001, Astrophys. J. 549, 1221.Google Scholar
  11. Glover, A., Ranns, N., Harra, L. K., and Culhane, J. L.: 2000, Geophys. Res. Lett. 27, 2161.Google Scholar
  12. Gopalswamy, N., Lara, A., Lepping, R. P., Kaiser, M. L., Berdichevsky, D., and St. Cyr, O. C.: 2000, Geophys. Res. Lett. 27, 145.Google Scholar
  13. Gosling, J. T.: 1999, in M. R. Brown, R. C. Canfield, and A. A. Pevtsov (eds.), Magnetic Helicity in Space and Laboratory Plasmas, American Geophysical Union, Washington, D.C., p. 205.Google Scholar
  14. Leamon, R. J., Canfield, R. C., and Pevtsov, A. A.: 2002, J. Geophys. Res., in press.Google Scholar
  15. Marubashi, K.: 1997, in N. Crooker, J. A. Joselyn, and J. Feynman (eds.), Coronal Mass Ejections, American Geophysical Union, Washington, D.C., p. 147.Google Scholar
  16. Moore, R. L., Sterling, A. C., Hudson, H. S., and Lemen, J. R.: 2001, Astrophys. J. 552, 833.Google Scholar
  17. Pevtsov, A. A. and Canfield, R. C.: 2001, J. Geophys. Res. 106, 25191.Google Scholar
  18. Pevtsov, A. A., Canfield, R. C., and McClymont, A. N.: 1997, Astrophys. J. 481, 973.Google Scholar
  19. Pevtsov, A. A., Canfield, R. C., and Zirin, H.: 1996, Astrophys. J. 473, 533.Google Scholar
  20. Priest, E. R.: 1984, Solar Magneto-Hydrodynamics, D. Reidel Publ. Co., Dordrecht, Holland.Google Scholar
  21. Rust, D. M.: 1999, in M. R. Brown, R. C. Canfield, and A. A. Pevtsov (eds.), Magnetic Helicity in Space and Laboratory Plasmas, American Geophysical Union, Washington, D.C., p. 221.Google Scholar
  22. Shibata, K.: 1999, in M. R. Brown, R. C. Canfield, and A. A. Pevtsov (eds.), Magnetic Helicity in Space and Laboratory Plasmas, American Geophysical Union, Washington, D.C., p. 229.Google Scholar
  23. Sterling, A. C. and Hudson, H. S.: 1997, Astrophys. J. 491, L55.Google Scholar
  24. Sterling, A. C., Hudson, H. S., Thompson, B. J., and Zarro, D. M.: 2000, Astrophys. J. 532, 628.Google Scholar
  25. Tang, F.: 1986, Solar Phys. 105, 399.Google Scholar
  26. Tsuneta, S. et al.: 1991, Solar Phys. 136, 37.Google Scholar
  27. Webb, D. and Hundhausen, A.: 1987, Solar Phys. 108, 383.Google Scholar
  28. Webb, D., Cliver, E., Crooker, N., St. Cyr, O. C., and Thompson, B.: 2000, J. Geophys. Res. 105, 7491.Google Scholar
  29. Wood, B. E., Karovska, M., Chen, J., Brueckner, G. E., Cook, J. W., and Howard, R. A.: 1999, Astrophys. J. 512, 484.Google Scholar
  30. Yurchyshyn, V. B., Wang, H., Goode, P. R., and Deng, Y.: 2001, Astrophys. J. 563, 381.Google Scholar

Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  • Alexei A. Pevtsov
    • 1
  1. 1.National Solar Observatory/Sacramento PeakSunspotU.S.A.

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