Time-Resolved Stokes V Polarimetry of Small-Scale Magnetic Structures on the Sun

  • B. Fleck
Conference paper
Part of the Reviews in Modern Astronomy book series (MOD.ASTRONOMY, volume 4)

Abstract

We address problems of the dynamics of small-scale magnetic fluxtube concentrations by analyzing high spatial resolution time series of spectra of selected lines taken simultaneously in left-hand and right-hand circularly polarized light. This approach is complementary to the one of the Zürich group. Our observations were obtained with the Vacuum Tower Telescope and the Echelle spectrograph at Izaña, Tenerife. The spectral range covered the lines of Fe 6302.5Å and Fe 6301.5Å. All parameters extracted from the Stokes V and Stokes I profiles (except the Stokes V line ratio) reveal significant spatio-temporal variations. The dominant oscillatory signal in the velocity data is due to the 5-min oscillations. Of special interest are the strong spatially and temporally varying differences between the (I+V) and (I−V) spectra in the magnetic structures. They cause large differences between the velocities deduced from the Stokes I profile and the Stokes V zero-crossing wavelength (up to 1 km/s), whereas their spatio-temporal averages are almost identical. We observe also an anticorrelation between the amplitude and asymmetry of the Stokes V profile.

Keywords

Convection Depression Attenuation Coherence Calcite 

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References

  1. Abdelatif, T.E.: 1988, Ap. J. 333, 395CrossRefADSGoogle Scholar
  2. Beckers, J.M., Schröter, E.H.: 1968, Solar Phys. 4, 142CrossRefADSGoogle Scholar
  3. Cavallini, F., Ceppatelli, G., Righini, A., Alamanni, N.: 1986, Astron. Astrophys. 156, 310ADSGoogle Scholar
  4. Cram, L.E., Wilson, P.R.: 1975, Solar Phys. 41, 313CrossRefADSGoogle Scholar
  5. Defouw, R.J.: 1976, Astrophys. J. 209, 266CrossRefADSGoogle Scholar
  6. Dunn, R.B., Zirker, J.B.: 1973, Solar Phys. 33, 281ADSGoogle Scholar
  7. Edwin, P.M., Roberts, B.: 1982, Solar Phys. 76, 239CrossRefADSGoogle Scholar
  8. Edwin, P.M., Roberts, B.: 1983, Solar Phys. 88, 179CrossRefADSGoogle Scholar
  9. Evans, D.J., Roberts, B.: 1990, Ap. J. 348, 346CrossRefADSGoogle Scholar
  10. Deubner, F.-L.: 1974, Solar Phys. 39, 31CrossRefADSGoogle Scholar
  11. Fleck, B., Deubner, F.-L.: 1989, Astron. Astrophys. 224, 245ADSGoogle Scholar
  12. Fleck, B., Deubner, F.-L.: 1990, in The Dynamic Sun, Proc. of the 6th European Meeting on Solar Physics, Publ. Debrecen Obs. 7, 306Google Scholar
  13. Fleck, B., Deubner, F.-L.: 1991, in Mechanisms of Chromospheric and Coronal Heating, ed. P. Ulmschneider, Springer, in printGoogle Scholar
  14. Giovanelli, R.G., Livingston, W.C., Harvey, J.W.: 1978, Solar Phys. 59, 49CrossRefADSGoogle Scholar
  15. Grossmann-Doerth, U., Knölker, M., Schüssler, M., E.: 1989, in Solar and Stellar Granulation, eds. R.J. Rutten and G. Severino; NATO ASI Series C 263, p. 481Google Scholar
  16. Grossmann-Doerth, U., Schüssler, M., Solanki, S.K.: 1988, Astron. Astrophys. 206, L37ADSGoogle Scholar
  17. Grossmann-Doerth, U., Schüssler, M., Solanki, S.K.: 1989, Astron. Astrophys. 221, 341ADSGoogle Scholar
  18. Hammer, R.: 1987, in The Role of Fine-Scale Magnetic Fields on the Structure of the Solar Atmosphere, eds. E.H. Schröter, M. Vazques, and A.A. Wyller, Cambridge University Press, p. 255Google Scholar
  19. Keller, C.U., Solanki, S.K., Tarbell, T.D., Title, A.M., Stenflo, J.O.: 1990, Astron. Astrophys. 236, 250ADSGoogle Scholar
  20. Lites, B.W., Chipman, W.: 1979, Ap. J. 231, 570CrossRefADSGoogle Scholar
  21. Mihalas, D., Mihalas, B.W.: 1984, Foundations of Radiation Hydrodynamics, Oxford Univ. Press, New YorkMATHGoogle Scholar
  22. Muller, R.: 1989, in Solar and Stellar Granulation, eds. R.J. Rutten and G. Severino; NATO ASI Series C 263, p. 101Google Scholar
  23. Pantellini, F.G.E., Solanki, S., Stenflo, J.O.: 1988, Astron. Astrophys. 189, 263ADSGoogle Scholar
  24. Parker, E.N.: 1983, Ap. J. 264, 642CrossRefADSGoogle Scholar
  25. Parker, E.N.: 1991, in Mechanisms of Chromospheric and Coronal Heating, ed. P. Ulmschneider, Springer, in printGoogle Scholar
  26. Rees, D.E., Semel, M.: 1979, Astron. Astrophys. 74, 1ADSGoogle Scholar
  27. Rimmele, Th., von der Lühe, O.: 1990, Rev. Mod. Astron. 2, 105ADSGoogle Scholar
  28. Roberts, B.: 1981a, Solar Phys. 69, 27CrossRefADSGoogle Scholar
  29. Roberts, B.: 1981b, Solar Phys. 69, 39CrossRefADSGoogle Scholar
  30. Roberts, B.: 1983, Solar Phys. 87, 77CrossRefADSGoogle Scholar
  31. Roberts, B., Webb, A.R.: 1978, Solar Phys. 56, 5CrossRefADSGoogle Scholar
  32. Roberts, B., Webb, A.R.: 1979, Solar Phys. 77, 5Google Scholar
  33. Roca-Cortes, T., Vazquez, M., Wohl, H.: 1983, Solar Phys. 88, 1CrossRefADSGoogle Scholar
  34. Roddier, F.: 1967, Ap. J. 147, 1113CrossRefADSGoogle Scholar
  35. Ryutova, M.P.: 1990, in Solar Photosphere: Structure, Convection and Magnetic Fields, ed. J.O. Stenflo, IAU-Symp. No. 138, Kiev, p. 229Google Scholar
  36. Schmieder, B.: 1976, Solar Phys. 47, 435CrossRefADSGoogle Scholar
  37. Scholiers, W., Wiehr, E.: 1985, Solar Phys. 99, 349CrossRefADSGoogle Scholar
  38. Schrijver, C.J.: 1987, Astron. Astrophys. 172, 111ADSGoogle Scholar
  39. Schrijver, C.J.: 1991, in Mechanisms of Chromospheric and Coronal Heating, ed. P. Ulmschneider, Springer, in printGoogle Scholar
  40. Schüssler, M.: 1987, in The Role of Fine-Scale Magnetic Fields on the Structure of the Solar Atmosphere, eds. E.H. Schröter, M. Vazques, and A.A. Wyller, Cambridge University Press, p. 223Google Scholar
  41. Schüssler, M.: 1990, in Solar Photosphere: Structure, Convection and Magnetic Fields, ed. J.O. Stenflo, IAU-Symp. No. 138, Kiev, p. 161Google Scholar
  42. Snider, J.L.: 1970, Solar Phys. 12, 352CrossRefADSGoogle Scholar
  43. Solanki, S.K.: 1986, Astron. Astrophys. 168, 311ADSGoogle Scholar
  44. Solanki, S.K.: 1987, in The Role of Fine-Scale Magnetic Fields on the Structure of the Solar Atmosphere, eds. E.H. Schröter, M. Vazques, and A.A. Wyller, Cambridge University Press, p. 67Google Scholar
  45. Solanki, S.K.: 1989, Astron. Astrophys. 224, 225ADSGoogle Scholar
  46. Solanki, S.K.: 1990, in Solar Photosphere: Structure, Convection and Magnetic Fields, ed. J.O. Stenflo, IAU-Symp. No. 138, Kiev, p. 103Google Scholar
  47. Spruit, H.C.: 1981a, in The Sun as a Star, ed. S. Jordan, NASA SP-450, p. 385Google Scholar
  48. Spruit, H.C.: 1981b, Astron. Astrophys. 98, 155MATHADSGoogle Scholar
  49. Spruit, H.C.: 1982, Solar Phys. 75, 3CrossRefADSGoogle Scholar
  50. Spruit, H.C., Roberts, B.: 1983, Nature 304, 401CrossRefADSGoogle Scholar
  51. Stenflo, J.O.: 1989, Astron. Astrophys. Rev. 1, 3CrossRefADSGoogle Scholar
  52. Stenflo, J.O., Harvey, J.W.: 1985, Solar Phys. 95, 99CrossRefADSGoogle Scholar
  53. Stenflo, J.O., Harvey, J.W., Brault, J.W., Solanki, S.: 1984, Astron. Astrophys. 131, 333ADSGoogle Scholar
  54. Tarbell, T.D., Title, A.M., Schoolman, S.A.: 1979, Ap. J. 229, 387Google Scholar
  55. Topka, K.P., Tarbell, T.D., Title, A.M.: 1986, Ap. J. 306, 304CrossRefADSGoogle Scholar
  56. Ulmschneider, P.: 1991, in Mechanisms of Chromospheric and Coronal Heating, ed. P. Ulmschneider, Springer, in printGoogle Scholar
  57. Ulmschneider, P., Muchmore, D.: 1986, in Small Scale Magnetic Flux Concentrations in the Solar Photosphere, eds. W. Deinzer, M. Kn”olker and H.H. Voigt, Vandenhoeck&Ruprecht, Göttingen, p. 169Google Scholar
  58. von der Lühe, O., Widener, A.L., Rimmele, Th., Spence, G., Dunn, R.B., Wiborg, P.: 1989, Astron. Astrophys. 224, 351ADSGoogle Scholar
  59. Webb, A.R., Roberts, B.: 1980a, Solar Phys. 68, 71CrossRefADSGoogle Scholar
  60. Webb, A.R., Roberts, B.: 1980b, Solar Phys. 68, 87CrossRefADSGoogle Scholar
  61. Wentzel, D.G.: 1979, Astron. Astrophys. 76, 20MATHADSGoogle Scholar
  62. Wiehr, E.: 1985, Astron. Astrophys. 149, 217ADSGoogle Scholar
  63. Wilson, P.R.: 1979, Astron. Astrophys. 71, 9MATHADSGoogle Scholar
  64. Zayer, I., Solanki, S., Stenflo, J.O.: 1989, Astron. Astrophys. 211, 463ADSGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1991

Authors and Affiliations

  • B. Fleck
    • 1
  1. 1.Institut für Astronomie und AstrophysikWürzburgFed. Rep. of Germany

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