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Stellar Granulation and Photospheric Line Asymmetries

Published online by Cambridge University Press:  19 July 2016

Dainis Dravins
Dainis Dravins*
Affiliation:
Lund Observatory, Box 43, S-22100 Lund, Sweden

Abstract

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The fine structure of stellar photospheric convection (the stellar equivalent of solar granulation) can be analyzed with the aid of high-resolution spectroscopy. Photospheric absorption lines are slightly asymmetric and wavelength–shifted due to unequal photon contributions from bright and systematically Doppler–shifted granules and from darker intergranular areas. Numerical simulations of stellar surface convection in different stars have now been carried out, and such three–dimensional and time–dependent models predict the detailed stellar line profiles (including asymmetries and wavelength shifts), thus enabling a direct confrontation between observations and theory.

Type
IV. Spectroscopic Patterns of Stellar Atmospheres
Information
Symposium - International Astronomical Union , Volume 132: The Impact of Veryhigh S/N Spectroscopy on Stellar Physics , 1988 , pp. 239 - 247
Copyright
Copyright © Kluwer 1988 

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