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Open Astronomy

formerly Baltic Astronomy

Editor-in-Chief: Barbuy, Beatriz

IMPACT FACTOR 2018: 0.350

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Volume 27, Issue 1


On Milne–Barbier–Unsöld relationships

Frédéric Paletou
Published Online: 2018-04-14 | DOI: https://doi.org/10.1515/astro-2018-0018


This short review aims to clarify upon the origins of so-called Eddington-Barbier relationships, which relate the emergent specific intensity and the flux to the photospheric source function at specific optical depths. Here we discuss the assumptions behind the original derivation of Barbier (1943).We also point to the fact that Milne had already formulated these two relations in 1921.

Keywords: Radiative transfer; analytical methods; education; history


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About the article

Received: 2017-10-27

Accepted: 2017-12-23

Published Online: 2018-04-14

Citation Information: Open Astronomy, Volume 27, Issue 1, Pages 76–79, ISSN (Online) 2543-6376, DOI: https://doi.org/10.1515/astro-2018-0018.

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© 2018, published by De Gruyter. This work is licensed under the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 License. BY-NC-ND 4.0

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