Shifting of the resonance location for planets embedded in circumstellar disks
Abstract
Context. In the early evolution of a planetary system, a pair of planets may be captured in a mean motion resonance while still embedded in their nesting circumstellar disk.
Aims: The goal is to estimate the direction and amount of shift in the semimajor axis of the resonance location due to the disk gravity as a function of the gas density and mass of the planets. The stability of the resonance lock when the disk dissipates is also tested.
Methods: The orbital evolution of a large number of systems is numerically integrated within a three-body problem in which the disk potential is computed as a series of expansion. This is a good approximation, at least over a limited amount of time.
Results: Two different resonances are studied: the 2:1 and the 3:2. In both cases the shift is inwards, even if by a different amount, when the planets are massive and carve a gap in the disk. For super-Earths, the shift is instead outwards. Different disk densities, Σ, are considered and the resonance shift depends almost linearly on Σ. The gas dissipation leads to destabilization of a significant number of resonant systems, in particular if it is fast.
Conclusions: The presence of a massive circumstellar disk may significantly affect the resonant behavior of a pair of planets by shifting the resonant location and by decreasing the size of the stability region. The disk dissipation may explain some systems found close to a resonance but not locked in it.
- Publication:
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Astronomy and Astrophysics
- Pub Date:
- March 2018
- DOI:
- 10.1051/0004-6361/201732070
- arXiv:
- arXiv:1712.04178
- Bibcode:
- 2018A&A...611A..37M
- Keywords:
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- planet-disk interactions;
- Astrophysics - Earth and Planetary Astrophysics
- E-Print:
- Accepted for publication on A&