Indicators of Mass in Spherical Stellar Atmospheres
| Autor: | John B. Lester, Hilding R. Neilson, Rayomond Dinshaw |
|---|---|
| Rok vydání: | 2013 |
| Předmět: |
Physics
010504 meteorology & atmospheric sciences Red giant Stellar atmosphere FOS: Physical sciences Astronomy and Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics Radius Astrophysics Type (model theory) 01 natural sciences Spectral line Luminosity Spherical model Astrophysics - Solar and Stellar Astrophysics 13. Climate action Space and Planetary Science 0103 physical sciences Astrophysics::Solar and Stellar Astrophysics Red supergiant Astrophysics::Earth and Planetary Astrophysics 010303 astronomy & astrophysics Solar and Stellar Astrophysics (astro-ph.SR) Astrophysics::Galaxy Astrophysics 0105 earth and related environmental sciences |
| Zdroj: | Publications of the Astronomical Society of the Pacific. 125:335-343 |
| ISSN: | 1538-3873 0004-6280 |
| DOI: | 10.1086/670255 |
| Popis: | Mass is the most important stellar parameter, but it is not directly observable for a single star. Spherical model stellar atmospheres are explicitly characterized by their luminosity ($L_\star$), mass ($M_\star$) and radius ($R_\star$), and observations can now determine directly $L_\star$ and $R_\star$. We computed spherical model atmospheres for red giants and for red supergiants holding $L_\star$ and $R_\star$ constant at characteristic values for each type of star but varying $M_\star$, and we searched the predicted flux spectra and surface-brightness distributions for features that changed with mass. For both stellar classes we found similar signatures of the star's mass in both the surface-brightness distribution and the flux spectrum. The spectral features have been use previously to determine $\log_{10} (g)$, and now that the luminosity and radius of a non-binary red giant or red supergiant can be observed, spherical model stellar atmospheres can be used to determine the star's mass from currently achievable spectroscopy. The surface-brightness variations with mass are slightly smaller than can be resolved by current stellar imaging, but they offer the advantage of being less sensitive to the detailed chemical composition of the atmosphere. 24 pages, 9 figures |
| Databáze: | OpenAIRE |
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