2012/04/18 by V. V. Kovtyukh, N. Gorlova, S. I. Belik · 2 citations
Physics and Astronomy · #Absolute magnitude #Abundance (ecology) #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Effective temperature #Galaxy #Gamma-ray bursts and supernovae #Luminosity #Physics #Spectral line #Stars #Stellar, planetary, and galactic studies #Supergiant #Surface gravity #astro-ph.SR
paper · pdf · doi:10.1111/j.1365-2966.2012.21117.x
7 pages, accepted to MNRAS
arxiv created 2012/04/18 · openalex publication_date 2012/05/16 · arxiv updated 2015/06/04 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The oxygen λ7771–4 Å triplet is a good indicator of luminosity in A–G supergiants. However, its strength also depends on other atmospheric parameters. In this study, we present the luminosity calibrations where, for the first time, the effects of the effective temperature, microturbulent velocity, surface gravity and the abundance have been disentangled. The calibrations are derived on the basis of a data set of high-dispersion spectra of 60 yellow supergiants with highly reliable luminosities and accurate atmospheric parameters. This allowed us to bring the uncertainty of the triplet-based absolute magnitudes down to 0.26 mag. The calibrations are suitable for spectral types F0–K0 and luminosity classes I–II, covering absolute magnitudes Mv from −1.0 to −10 mag.