Accurate luminosities for F-G supergiants from Fe ii / Fe i line depth ratios
| Autor: | R. E. Luck, V. V. Kovtyukh, S. I. Belik, M. P. Yasinskaya, F. A. Chekhonadskikh, Caroline Soubiran |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
Physics
Absolute magnitude 010504 meteorology & atmospheric sciences Cepheid variable Astrophysics::High Energy Astrophysical Phenomena Astronomy Astronomy and Astrophysics Astrophysics::Cosmology and Extragalactic Astrophysics Astrophysics Effective temperature Stellar classification 01 natural sciences Luminosity Stars Space and Planetary Science 0103 physical sciences Astrophysics::Solar and Stellar Astrophysics Supergiant 010303 astronomy & astrophysics Astrophysics::Galaxy Astrophysics 0105 earth and related environmental sciences Line (formation) |
| Zdroj: | Monthly Notices of the Royal Astronomical Society. 408:1568-1575 |
| ISSN: | 0035-8711 |
| DOI: | 10.1111/j.1365-2966.2010.17217.x |
| Popis: | Luminous FG supergiants can be used as extragalactic distance indicators. In order to fully exploit the properties of these bright stars, we must first learn how to measure their luminosities. Based primarily on classical Cepheids and supergiants in clusters and OB associations, we have derived 80 empirical relations connecting the line depth ratios of Fe ii/Fe i lines with the absolute magnitudes Mv and the effective temperatures Teff. These relations have been applied to estimate the absolute magnitudes of 98 FG supergiants with an error of ±0.26 mag. The application range of our calibrations is spectral types F2–G8 and luminosity classes I and II (absolute magnitudes Mv, −0.5 to −8 mag). A comparison of our Mv determinations with values from the literature shows good agreement. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Plný text