Accurate luminosities from the oxygen λ7771–4 Å triplet and the fundamental parameters of F–G supergiants

  title={Accurate luminosities from the oxygen $\lambda$7771–4 {\AA} triplet and the fundamental parameters of F–G supergiants},
  author={Valery V. Kovtyukh and Nadiya Gorlova and S. I. Belik},
  journal={Monthly Notices of the Royal Astronomical Society},
The oxygen λ7771–4 A 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… Expand

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