Simple Unified Spectroscopic Indicator of Stellar Luminosity: The Extended Flux-weighted Gravity-Luminosity Relationship

Kudritzki, Rolf-Peter; Urbaneja, Miguel A.; Rix, Hans-Walter (2020): Simple Unified Spectroscopic Indicator of Stellar Luminosity: The Extended Flux-weighted Gravity-Luminosity Relationship. In: Astrophysical Journal, Vol. 890, No. 1, 28

Abstract

We show that for a wide range of stellar masses, from 0.3 to 20 M-circle dot, and for evolutionary phases from the main sequence to the beginning of the red giant stage, the stellar flux-weighted gravity, g(F) equivalent to g/T-eff(4), is tightly correlated with absolute bolometric magnitude M-bol. Such a correlation is predicted by stellar evolution theory. We confirm this relation observationally, using a sample of 445 stars with precise stellar parameters. It holds over 17 stellar magnitudes from M-bol = 9.0 to -8.0 mag with a scatter of 0.17 mag above M-bol = -3.0 and 0.29 mag below this value. We then test the relation with 2.2 million stars with 6.5 mag >= M-bol >= 0.5 mag, where "mass-produced" but robust log g, T-eff, and M-bol from LAMOST DR5 and Gaia DR2 are available. We find that the same relation holds with a scatter of similar to 0.2 mag for single stars offering a simple spectroscopic distance estimate good to similar to 10%.

• Item Type: Journal article
• Faculties: Physics
• Subjects: 500 Science > 530 Physics
• ISSN: 0004-637X
• Language: English