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The formation of Mgi4571 Å in the solar atmosphere

✍ Scribed by Richard C. Altrock; C. J. Cannon

Publisher
Springer
Year
1973
Tongue
English
Weight
624 KB
Volume
29
Category
Article
ISSN
0038-0938

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✦ Synopsis

An analysis of the 4571 A line of neutral magnesium is presented in which one-dimensional macroscopic velocity fields are included. It is shown that gradients over restricted heights in the vertical and horizontal components of the velocity field of order --0.005 s -1 and --0.004 s -1 (such that velocity towards the observer decreases as height increases), respectively, result in asymmetries in the computed line profile similar to those observed. The heights in the solar atmosphere at which these velocity gradients exist are shown to be very critical in reproducing the observations. It was found that the best results were obtained when the gradients existeO in the height range from ~ 200 km to 300 km below the temperature minimum. The results indicate that for the Mg 1 4571 A line model calculations that do not include one-dimensional flow velocities may safely be compared with frequency-averaged observations.

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