The puzzling high velocity G5 supergiant star HD 179821: new insight from Gaia DR2 data
Abstract
HD 179821 is classified as G5 Ia star. From the IRAS colors and spectral energy distributions it was classified as a post-AGB star. But some studies classify it as a massive (30 to \(19~\mbox{M}_{\odot}\)) post-red supergiant evolving to become a Type II supernova. Its mass and evolutionary status remained a hotly debated question even after several detailed spectroscopic studies as the distance was not known. We use the parallax of HD 179821 from the second Gaia data release, and deduce its distance \(2959 \pm 409~\mbox{pc}\) and its absolute magnitude \(\mbox{MV} = -5.7 \pm 0.3\). Using the absolute magnitude determined in this paper, we show that HD 179821 fits very well with post-AGB tracks in the \(H-R\) diagram. Our results clearly confirm that HD 179821 is a post-AGB star of mass in the range of 0.70 to 0.75 solar mass. It is not a \(30~\mbox{M}_{\odot}\) red supergiant. The progenitor mass of this post-AGB star may be in the range of \(4~\mbox{M}_{\odot}\) but may be a bit more.
Keywords
Stars: AGB and post-AGB Stars: individual: HD179821 Stars: distances Stars: evolutionNotes
Acknowledgements
This study has made use of the SIMBAD database, the VizieR catalogue access tool and of NASA’s Astrophysics Data System, operated at CDS, Strasbourg, France. The authors are grateful to Olivia Mancuso for her review of English phrasing and grammar in this article.
References
- Arkhipova, V.P., Esipov, V.F., Ikonnikova, N.P., et al.: Astron. Lett. 35, 764 (2009) ADSCrossRefGoogle Scholar
- Bailer-Jones, C.A.L., Rybizki, J., Fouesneau, M., Mantelet, G., Andrae, R.: Astron. J. 156, 58 (2018) ADSCrossRefGoogle Scholar
- Buscombe, W.: MK spectral classifications. Sixth general catalogue (1984) Google Scholar
- Ekström, S., Georgy, C., Eggenberger, P., et al.: Astron. Astrophys. 537, A146 (2012) CrossRefGoogle Scholar
- Ferguson, B.A., Ueta, T.: Astrophys. J. 711, 613 (2010) ADSCrossRefGoogle Scholar
- Gaia Collaboration: VizieR Online Data Catalog p. 1345 (2018) Google Scholar
- Hawkins, G.W., et al.: Astrophys. J. 452, 314 (1995) ADSCrossRefGoogle Scholar
- Høg, E., Fabricius, C., Makarov, V.V., et al.: Astron. Astrophys. 355, L27 (2000) ADSGoogle Scholar
- Hrivnak, B.J., Kwok, S., Volk, K.M.: Astrophys. J. 346, 265 (1989) ADSCrossRefGoogle Scholar
- Ikonnikova, N.P., Taranova, O.G., Arkhipova, V.P., et al.: Astron. Lett. 44, 457 (2018) ADSCrossRefGoogle Scholar
- Josselin, E., Lèbre, A.: In: Szczerba, R., Gorny, S.K. (eds.) Astrophysics and Space Science Library, vol. 265 (2001) Google Scholar
- Jura, M., Werner, M.W.: Astrophys. J. 525, 113 (1999) ADSCrossRefGoogle Scholar
- Jura, M., Velusamy, T., Werner, M.W.: Astrophys. J. 556, 408 (2001) ADSCrossRefGoogle Scholar
- Kastner, J.H., Weintraub, D.A.: Astrophys. J. 452, 833 (1995) ADSCrossRefGoogle Scholar
- Keenan, P.C.: Bulletin d’Information du Centre de Donnees Stellaires, vol. 24, p. 19 (1983) Google Scholar
- Keenan, P.C., McNeil, R.C.: Astrophys. J. Suppl. Ser. 71, 245 (1989) ADSCrossRefGoogle Scholar
- Kipper, T.: Balt. Astron. 17, 87 (2008) ADSGoogle Scholar
- Le Coroller, H., Lèbre, A., Gillet, D., Chapellier, E.: Astron. Astrophys. 400, 613 (2003) ADSCrossRefGoogle Scholar
- Miller Bertolami, M.M.: Astron. Astrophys. 588, A25 (2016) ADSCrossRefGoogle Scholar
- Parthasarathy, M., Pottasch, S.R.: Astron. Astrophys. 161, 417 (1986) ADSGoogle Scholar
- Pottasch, S.R., Parthasarathy, M.: Astron. Astrophys. 192, 182 (1988) ADSGoogle Scholar
- Reddy, B.E., Hrivnak, B.J.: Astron. J. 118, 1900 (1999) ADSCrossRefGoogle Scholar
- Sahin, T., Lambert, D.L., Klochkova, V.G., Panchuk, V.E.: Mon. Not. R. Astron. Soc. 461, 4071 (2016) ADSCrossRefGoogle Scholar
- Sartoretti, P., Katz, D., Cropper, M., et al.: Astron. Astrophys. 616, A6 (2018) CrossRefGoogle Scholar
- Thèvenin, F., Parthasarathy, M., Jasniewicz, G.: Astron. Astrophys. 359, 138 (2000) ADSGoogle Scholar
- Zacs, L., Klochkova, V.G., Panchuk, V.E., Spelmanis, R.: Mon. Not. R. Astron. Soc. 282, 1171 (1996) ADSCrossRefGoogle Scholar
- Zuckerman, B., Dyck, H.M.: Astrophys. J. 311, 345 (1986) ADSCrossRefGoogle Scholar