Orbital architectures of planet-hosting binaries – II. Low mutual inclinations between planetary and stellar orbits

Autor: Trent J Dupuy, Adam L Kraus, Kaitlin M Kratter, Aaron C Rizzuto, Andrew W Mann, Daniel Huber, Michael J Ireland
Rok vydání: 2022
Předmět:
Zdroj: Monthly Notices of the Royal Astronomical Society. 512:648-660
ISSN: 1365-2966
0035-8711
Popis: Planet formation is often considered in the context of one circumstellar disk around one star. Yet stellar binary systems are ubiquitous, and thus a substantial fraction of all potential planets must form and evolve in more complex, dynamical environments. We present the results of a five-year astrometric monitoring campaign studying 45 binary star systems that host Kepler planet candidates. The planet-forming environments in these systems would have literally been shaped by the binary orbits that persist to the present day. Crucially, the mutual inclinations of star-planet orbits can only be addressed by a statistical sample. We describe in detail our sample selection and Keck/NIRC2 laser guide star adaptive optics observations collected from 2012 to 2017. We measure orbital arcs, with a typical accuracy of ~0.1 mas/yr, that test whether the binary orbits tend to be aligned with the edge-on transiting planet orbits. We rule out randomly-distributed binary orbits at 4.7$\sigma$, and we show that low mutual inclinations are required to explain the observed orbital arcs. If the stellar orbits have a field binary-like eccentricity distribution, then the best match to our observed orbital arcs is a distribution of mutual inclinations ranging from 0-30 degrees. We discuss the implications of such widespread planet-binary alignment in the theoretical context of planet formation and circumstellar disk evolution.
Comment: Accepted to MNRAS
Databáze: OpenAIRE
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