BD+14${}^{\circ }$3061: A Luminous Yellow Post-AGB Star in the Galactic Halo

Abstract

I report the discovery that the 9th-magnitude Galactic-halo star BD+14${}^{\circ }$3061 is a member of the rare class of luminous metal-poor "yellow post-AGB" stars. Its Gaia DR2 parallax implies an absolute magnitude of $M_V=-3.44\pm 0.27$, and it is a very high-velocity star moving in a retrograde Galactic orbit. BD+14${}^{\circ }$3061 is a field analog of the half-dozen yellow PAGB stars known in Galactic globular clusters, which have closely similar absolute magnitudes. These objects are the visually brightest members of old stellar populations; their apparently narrow luminosity function makes them potentially useful as Population II standard candles. The spectral-energy distribution of BD+14${}^{\circ }$3061 out to $22\mu$m shows no evidence for circumstellar dust. The star is a low-amplitude semi-regular pulsating variable, with typical periods of 30-32 days. A radial-velocity study suggests that it is a spectroscopic binary with a period of 429.6 days, making it similar to known binary yellow PAGB stars such as HD 46703 and BD+39${}^{\circ }$4926.

Accepted by Astronomical Journal

References in corpus (4)

• Three-dimensional mapping of the local interstellar medium with composite data
• Keplerian discs around post-AGB stars: a common phenomenon?
• Modelling depletion by re-accretion of gas from a dusty disc in post-AGB stars
• A Spectroscopic and Photometric Study of the Metal-Poor, Pulsating, Post-AGB Binary HD 46703

Cited by in corpus (3)

• Two Luminous Post-AGB Stars in the Galactic Globular Cluster M19
• Gaia DR2 and EDR3 data and evolutionary status of post-AGB stars with high radial velocities
• Yellow Post-Asymptotic-Giant-Branch Stars as Standard Candles. I. Calibration of the Luminosity Function in Galactic Globular Clusters