A Fast-growing Tilt Instability of Detached Circumplanetary Disks
Abstract
Accretion disks in binary systems can exhibit a tilt instability, arising from the interaction between components of the tidal potential and dissipation. Using a linear analysis, we show that the aspect ratios and outer radii of circumplanetary disks provide favorable conditions for tilt growth. We quantify the growth rate of the instability using particle-based (PHANTOM) and grid-based (ATHENA++) hydrodynamic simulations. For a disk with outer aspect ratio H/r ≃ 0.1, initially moderate tilts double on a timescale of about 15-30 binary orbits. Our results imply that detached circumplanetary disks, whose evolution is not entirely controlled by accretion from the circumstellar disk, may commonly be misaligned to the planetary orbital plane. We discuss implications for planetary spin evolution, and possible interactions between the tilt instability and Kozai-Lidov dynamics.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- July 2020
- DOI:
- 10.3847/2041-8213/aba3c1
- arXiv:
- arXiv:2007.05022
- Bibcode:
- 2020ApJ...898L..26M
- Keywords:
-
- Stellar accretion disks;
- Planet formation;
- Protoplanetary disks;
- Exoplanet formation;
- Planetary theory;
- Satellite formation;
- Circumstellar disks;
- Hydrodynamics;
- Pre-main sequence stars;
- Disk galaxies;
- Planetary system formation;
- Solar system planets;
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- 1241;
- 1300;
- 492;
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- 1963;
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- Astrophysics - Earth and Planetary Astrophysics
- E-Print:
- Accepted for publication in ApJL