Abstract
We report high resolution measurements of the center-to-limb variation of the Mgi line at 4571.1 Å. This forbidden line is of interest because it should be formed in LTE. Comparison of our measurements with the Harvard-Smithsonian Reference Atmosphere show that the line center radiation originates in the temperature minimum region from 330 to 550 km above the point where τ continuum = 1. Observations near the limb confirm that the temperature minimum is ∼4200K.
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The National Center for Atmospheric Research and Kitt Peak National Observatory are sponsored by the National Science Foundation.
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White, O.R., Altrock, R.C., Brault, J.W. et al. Measurements of the limb darkening in the forbidden Mgi line at 4571.1 Å. Sol Phys 23, 18–25 (1972). https://doi.org/10.1007/BF00153888
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DOI: https://doi.org/10.1007/BF00153888