• DOI:10.1086/423306
• Corpus ID: 118975170

The Double-lined Spectrum of LBV 1806–20

@article{Figer2004TheDS,
  title={The Double-lined Spectrum of LBV 1806–20},
  author={Donald F. Figer and Francisco Najarro and Rolf Peter Kudritzki},
  journal={The Astrophysical Journal Letters},
  year={2004},
  volume={610},
  pages={L109 - L112}
}

• D. Figer, F. Najarro, R. Kudritzki
• Published 14 June 2004
• Physics
• The Astrophysical Journal Letters

Despite much theoretical and observational progress, there is no known firm upper limit to the masses of stars. Our understanding of the interplay between the immense radiation pressure produced by massive stars in formation and the opacity of infalling material is subject to theoretical uncertainties, and many observational claims of "the most massive star" have failed the singularity test. LBV 1806-20 is a particularly luminous object, L ∼ 106 L⊙, for which some have claimed very high mass estimates (Minitial > 200 M⊙), based in part on its similarity to the Pistol star. We present high-resolution near-infrared spectroscopy of LBV 1806-20, showing that it is possibly a binary system with components separated in velocity by ∼70 km s-1. If correct, then this system is not the most massive star known, yet it is a massive binary system. We argue that a binary, or merged, system is more consistent with the ages of nearby stars in the LBV 1806-20 cluster. In addition, we find that the velocity of VLSR = 36 km s-1 is consistent with a distance of 11.8 kpc, a luminosity of 106.3 L⊙, and a system mass of ∼130 M⊙.