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  • Detailed Abundances of the Planet-hosting TOI-1173 A/B System: Possible Evidence of Planet Engulfment in a Very Wide Binary
Title: Detailed Abundances of the Planet-hosting TOI-1173 A/B System: Possible Evidence of Planet Engulfment in a Very Wide Binary
Abstract Over the last decade, studies of large samples of binary systems have identified chemical anomalies and shown that they might be attributed to planet formation or planet engulfment. However, both scenarios have primarily been tested in pairs without known exoplanets. In this work, we explore these scenarios in the newly detected planet-hosting wide binary TOI-1173 A/B (projected separation ∼11,400 au), using high-resolution MAROON-X and ARCES spectra. We determined photospheric stellar parameters both by fitting stellar models and via the spectroscopic equilibrium approach. Both analyses agree and suggest that they are cool main-sequence stars located in the thin disk. A line-by-line differential analysis between the components (B−A) displays an abundance pattern in the condensation temperature plane, where the planet-hosting star TOI-1173 A is enhanced in refractory elements such as iron by more than 0.05 dex. This suggests the engulfment of ∼18M⊕of rocky material in star A. Our hypothesis is supported by the dynamics of the system (detailed in our companion paper), which suggest that the super-Neptune TOI-1173 Abmight have been delivered to its current short period (∼7 days) through circularization and von Zeipel–Lidov–Kozai mechanisms, thereby triggering the engulfment of inner rocky exoplanets.  more » « less
Award ID(s):
2108465
PAR ID:
10647703
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
AAS
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
974
Issue:
1
ISSN:
0004-637X
Page Range / eLocation ID:
122
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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