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arXiv · 2503.19961

HD 144812: A transition-phase massive star in a binary system

Michalis Kourniotis·Michaela Kraus·Maria Laura Arias·Lydia S. Cidale
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Abstract

In this Letter, we shed light on the evolutionary phase of HD 144812, a Galactic yellow supergiant showing infrared excess that is typically expected for evolved stars undergoing enhanced mass-loss activity. We present high-resolution spectroscopy of the star in the $H-$ and $K-$band acquired with the GRating INfrared Spectrometer (IGRINS) and further explore multi-band imaging of the wider field of view from the ultraviolet to the radio regime. The IGRINS data reveal several lines from the hydrogen series and iron in a double-peaked emission and we here suggest, that HD 144812 is orbited by a disk-hosting companion. Furthermore, we report emission in the CO band heads of the star that is modeled to arise from a circum-stellar/binary disk (or ring) of ejected gas. The latter consists of material that is expected to have been dredged up from the core of the star to its surface during a prior phase as a red supergiant (RSG). These findings together suggest that HD 144812 is a rare, post-RSG star in a binary system, encouraging further investigation on the effect that the stellar encounters have on triggering instabilities and driving the evolution of the primary star shortly prior to the supernova event.

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Michalis Kourniotis, Michaela Kraus, Maria Laura Arias, Lydia S. Cidale. 2025-03-25. HD 144812: A transition-phase massive star in a binary system. https://arxiv.org/abs/2503.19961

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