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The center-to-limb variations of four Cailines in the photospheric spectrum at λ6500

✍ Scribed by P. Ambruoso; C. Marmolino; M. T. Gomez; G. Severino

Publisher
Springer
Year
1992
Tongue
English
Weight
722 KB
Volume
141
Category
Article
ISSN
0038-0938

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✦ Synopsis

We study the center-limb (CL) variation of the average profiles of four Cal lines near 26500 and compare these observations with synthetic data obtained from several line formation models having different thermal structures, line parameters, LTE and non-LTE conditions, and micro and macroturbulence values, to assess the formation characteristics of our Cal lines in the solar photosphere.

Comparison of numerical results with observations indicates that non-LTE is indispensable to fit the CL variation of the central residual intensity for the line 26493, and anisotropic microturbulence is indispensable to improve the CL behavior of the equivalent widths for all lines. The CaI line analysis favors a cool photospheric model, but this cannot be disentangled clearly from the effects of non-LTE and small-scale velocity fields on the grounds of the present line formation models.

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