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arXiv · 2009.11122

A new candidate Luminous Blue Variable

Donald F. Figer·Francisco Najarro·Maria Messineo·J. Simon Clark·Karl M. Menten
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Abstract

We identify IRAS 16115-5044, which was previously classified as a protoplanetary nebula (PPN), as a candidate luminous blue variable (LBV). The star has high luminosity (>10$^{5.75}$ L_Sun), ensuring supergiant status, has a temperature similar to LBVs, is photometrically and spectroscopically variable, and is surrounded by warm dust. Its near-infrared spectrum shows the presence of several lines of HI, He I, Fe II, Fe [II], MgII, and Na I with shapes ranging from pure absorption and P Cygni profiles to full emission. These characteristics are often observed together in the relatively rare LBV class of stars, of which only $\approx$20 are known in the Galaxy. The key to the new classification is the fact that we compute a new distance and extinction that yields a luminosity significantly in excess of those for post-AGB PPNe, for which the initial masses are <8 M_Sun. Assuming single star evolution, we estimate an initial mass of $\approx$40 M_Sun.

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Donald F. Figer, Francisco Najarro, Maria Messineo, J. Simon Clark, Karl M. Menten. 2020-09-23. A new candidate Luminous Blue Variable. https://doi.org/10.3847/2041-8213%2Fabb704

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