A New Candidate Luminous Blue Variable
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 (≳105.75 L⊙), 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 H I, He I, Fe II, Fe [II], Mg II, 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 ≈20 are known in the Galaxy. The key to the new classification is the fact that we compute a new distance and extinction that yield a luminosity significantly in excess of those for post-AGB PPNe, for which the initial masses are <8 M⊙. Assuming single star evolution, we estimate an initial mass of ≈40 M⊙.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- September 2020
- DOI:
- 10.3847/2041-8213/abb704
- arXiv:
- arXiv:2009.11122
- Bibcode:
- 2020ApJ...901L..15F
- Keywords:
-
- Luminous blue variable stars;
- Stellar evolution;
- Massive stars;
- Supergiant stars;
- Stellar mass loss;
- 944;
- 1599;
- 732;
- 1661;
- 1613;
- Astrophysics - Solar and Stellar Astrophysics;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- Published 2020 September 23 in ApJ Letters