Parametric study of polar configurations around binaries
Abstract
Dynamical studies suggest that most of the circumbinary discs (CBDs) should be coplanar. However, under certain initial conditions, the CBD can evolve toward polar orientation. Here we extend the parametric study of polar configurations around detached closein binaries through Nbody simulations. For polar configurations around binaries with mass ratios q below 0.7, the nominal location of the mean motion resonance (MMR) 1 : 4 predicts the limit of stability for e_{B} > 0.1. Alternatively, for e_{B} < 0.1 or q ∼ 1, the nominal location of the MMR 1 : 3 is the closest stable region. The presence of a giant planet increases the region of forbidden polar configurations around low mass ratio binaries with eccentricities e_{B}∼ 0.4 with respect to rocky earthlike planets. For equal mass stars, the eccentricity excitation Δβ of polar orbits smoothly increases with decreasing distance to the binary. For q < 1, Δβ can reach values as high as 0.4. Finally, we studied polar configurations around HD 98800BaBb and show that the region of stability is strongly affected by the relative positions of the nodes. The most stable configurations in the system correspond to polar particles, which are not expected to survive on longer timescales due to the presence of the external perturber HD 98800AaAb.
 Publication:

Journal of Physics Conference Series
 Pub Date:
 October 2019
 DOI:
 10.1088/17426596/1365/1/012023
 arXiv:
 arXiv:1907.08180
 Bibcode:
 2019JPhCS1365a2023G
 Keywords:

 Astrophysics  Earth and Planetary Astrophysics
 EPrint:
 9 pages. 7 figures. Accepted for publication in the special issue of the Journal of Physics: Conference Series aimed to the works presented at the Brazilian Colloquium on Orbital Dynamics  CBDO 2018