Chen, C. orcid.org/0000-0002-4489-3491, Martin, R.G. orcid.org/0000-0003-2401-7168, Lubow, S.H. orcid.org/0000-0002-4636-7348 et al. (1 more author) (2024) Tilted Circumbinary Planetary Systems as Efficient Progenitors of Free-floating Planets. The Astrophysical Journal Letters, 961 (1). L5. ISSN 2041-8205
Abstract
The dominant mechanism for generating free-floating planets has so far remained elusive. One suggested mechanism is that planets are ejected from planetary systems due to planet–planet interactions. Instability around a single star requires a very compactly spaced planetary system. We find that around binary star systems instability can occur even with widely separated planets that are on tilted orbits relative to the binary orbit due to combined effects of planet–binary and planet–planet interactions, especially if the binary is on an eccentric orbit. We investigate the orbital stability of planetary systems with various planet masses and architectures. We find that the stability of the system depends upon the mass of the highest-mass planet. The order of the planets in the system does not significantly affect stability, but, generally, the most massive planet remains stable and the lower-mass planets are ejected. The minimum planet mass required to trigger the instability is about that of Neptune for a circular orbit binary and a super-Earth of about 10 Earth masses for highly eccentric binaries. Hence, we suggest that planet formation around inclined binaries can be an efficient formation mechanism for free-floating planets. While most observed free-floating planets are giant planets, we predict that there should be more low-mass free-floating planets that are as of yet unobserved than higher-mass planets.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | © 2024. The Author(s). Published by the American Astronomical Society. Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 licence. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI. |
Dates: |
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Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Engineering & Physical Sciences (Leeds) > School of Physics and Astronomy (Leeds) > Astrophysics (Leeds) |
Depositing User: | Symplectic Publications |
Date Deposited: | 18 Jan 2024 14:21 |
Last Modified: | 18 Jan 2024 14:21 |
Published Version: | http://dx.doi.org/10.3847/2041-8213/ad17c5 |
Status: | Published |
Publisher: | American Astronomical Society |
Identification Number: | 10.3847/2041-8213/ad17c5 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:207893 |