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The solar H and K lines of ionized calcium


Photographic observations of the mean H and K profiles are given for several positions across the solar disk (0.1 < μ < 0.6). The core profiles of H and K are nearly identical at the same position on the sun.

Estimates of the mean Doppler width and the depth of formation of the K2 emission peaks are given. A more elaborate analysis confirms that the K2 peaks are formed in a relatively shallow layer (τ 0 ∼ 3) in which the Doppler width decreases rapidly inward. The relevance of these conclusions to current attempts to predict theoretically the H and K profiles is discussed.

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  • Athay, R. G.: 1967, private communication.

  • Babcock, H. W. and Babcock, H. D.: 1955, Astrophys. J. 121, 349.

    Google Scholar 

  • Evans, J. W. and Waddell, J. H.: 1962, Applied Optics 1, 111.

    Google Scholar 

  • Goldberg, L.: 1964, Astrophys. J. 140, 384.

    Google Scholar 

  • Goldberg, L., Mohler, O. C., and Mueller, E. A.: 1959, Astrophys. J. 129, 119.

    Google Scholar 

  • Houtgast, J.: 1965, Koninkl. Nederl. Akad. van Wetenschappen, Proc. B, 68, #5.

    Google Scholar 

  • Howard, R.: 1959, Astrophys. J. 130, 193.

    Google Scholar 

  • Jefferies, J. T. and Curtis, G. W.: 1965, Proc. Second Smithsonian Conferences on Stellar Atmospheres; Smithsonian Ap. Obs. Report #174.

  • Jefferies, J. T. and Thomas, R. N.: 1960, Astrophys. J. 131, 695.

    Google Scholar 

  • Jensen, E. and Orrall, F. Q.: 1963, Astrophys. J. 138, 252.

    Google Scholar 

  • Leighton, R. B.: 1959, Astrophys. J. 130, 366.

    Google Scholar 

  • Simon, G. and Leighton, R. B.: 1964, Astrophys. J. 140, 1120.

    Google Scholar 

  • Suemoto, Z.: 1963, Proc. Jap. Acad. 39, 463.

    Google Scholar 

  • Waddell, J. H.: 1962, Astrophys. J. 136, 231.

    Google Scholar 

  • White, O. R.: 1967, Private Communication.

  • White, O. R. and Suemoto, Z.: 1968, Solar Physics (in press).

  • Wilson, O. C.: 1963, Astrophys. J. 138, 832.

    Google Scholar 

  • Wilson, O. C. and Bappu, M. K. V.: 1957, Astrophys. J. 125, 661.

    Google Scholar 

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Zirker, J.B. The solar H and K lines of ionized calcium. Sol Phys 3, 164–180 (1968).

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  • Calcium
  • Emission Peak
  • Solar Disk
  • Shallow Layer
  • Doppler Width