Solar Physics

, Volume 212, Issue 2, pp 227–237 | Cite as

The Sun's immutable basal quiet atmosphere

  • W. Livingston
  • L. Wallace


We employ limb darkening, spectral energy distribution (color), and center-disk spectrum line strength to investigate photospheric temporal variability. Current limb-darkening curves agree to 1% with past observations taken at different epochs extending back to 1975. Concerning color, from the data of Labs and Neckel (Cox, 1999) we deduce that the solar limb is 1000 Å more red than disk center. But when integrated over the entire disk to represent the Sun-as-a-star, the color shift is only 30 Å. Color is therefore not a very sensitive indicator of full-disk photospheric change. We examine the center-disk time series for C 5380 Å and Fe 5379 Å equivalent width and the Ca K index. The ratio C 5380/Fe 5379 in equivalent width is 0.4221+0.00011 (± 0.00003) y−1, indicating secular change but with no cycle modulation. Converted to temperature this variance amounts to ± 0.028 K. This is in contrast to the full-disk cycle modulation of these lines reported by Gray and Livingston (1997b). Ca K index also exhibits no cycle variation at disk center. Taking into account these findings, plus the small fraction of the photosphere occupied by magnetic elements as revealed in high-resolution G-band pictures, we suggest that cycle magnetic fields thread through the basal atmosphere without physical effect; that the basal quiet atmosphere is observationally immutable to the magnetic cycle within the limits given above.


Energy Distribution Temporal Variability Sensitive Indicator Spectral Energy Disk Center 
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  1. Berger, T. E. and Title, A. M.: 1996, Astrophys. J. 463, 365.Google Scholar
  2. Berger, T. E. and Title, A. M.: 2001, Astrophys. J. 553, 449.Google Scholar
  3. Berger, T. E., Schrijver, C. J., Shine, R. A., Tarbell, T. D., Title, A. M., and Scharmer, G.: 1995, Astrophys. J. 454, 531.Google Scholar
  4. Cox, A. N. (ed.): 1999, Allen's Astrophysical Quantities, Springer-Verlag, New York, p. 353.Google Scholar
  5. de Toma, G., White, O. R., Chapman, G. A., Walton, S. R., Preminger, D. G., Cookson, A. M., and Harvey, K.: 2001, Astrophys. J. 549, L131.Google Scholar
  6. Fligge, M., Solanki, S. K., Unruh, Y. C., Fröhlich, C., and Wehrli, Ch.: 1998, Astron. Astrophys. 335, 709.Google Scholar
  7. Fröhlich, C.: 2002, private communication.Google Scholar
  8. Gray, D. F. and Livingston, W. C.: 1997a, Astrophys. J. 474, 798.Google Scholar
  9. Gray, D. F. and Livingston, W. C.: 1997b, Astrophys. J. 474, 802.Google Scholar
  10. Mitchell, W. E., Jr. and Livingston, W. C.: 1991, Astrophys. J. 372, 336.Google Scholar
  11. Neckel, H.: 2003, Solar Phys. 212, 239 (this issue).Google Scholar
  12. Neckel, H. and Labs, D.: 1970, Solar Phys. 15, 79.Google Scholar
  13. Neckel, H. and Labs, D.: 1994, Solar Phys. 153, 91.Google Scholar
  14. Pap, J., Anklin, M., Frölich, C., Wehrli, C., and Floyd, L.: 1999, Adv. Space Res. 24, 215.Google Scholar
  15. Petro, L. D., Foukal, P. V., and Kurucz, R. L.: 1985, Solar Phys. 98, 23.Google Scholar
  16. Petro, L. D., Foukal, P. V., Rosen, W. A., Kurucz, R. L., and Pierce, A. K.: 1984, Astrophys. J. 283, 426.Google Scholar
  17. Pierce, A. K. and Slaughter, C. D.: 1977, Solar Phys. 51, 25.Google Scholar
  18. White, O. R. and Livingston, W. C.: 1981, Astrophys. J. 249, 798.Google Scholar

Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  • W. Livingston
    • 1
  • L. Wallace
    • 2
  1. 1.National Solar ObservatoryTucsonU.S.A
  2. 2.Kitt Peak National ObservatoryTucsonU.S.A

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