Contributed Talk - Splinter Exoplanets

Thursday, 24 September 2020, 10:45   (virtual room D)

Parking planets in circumbinary discs

A.B.T. Penzlin, W. Kley, R.P. Nelson
Universität Tübingen, Queen Mary University of London

The Kepler mission found about a dozen circumbinary planets orbiting around both stars. The two most recent ones were discovered just this year, Kepler-1661b and TOI-1338b. While the number of observations is growing, until now simulations could not explain most of the close-in planet orbits at distance of about 3.5 binary separation. As the tidally perturbed inner disc does not allow in-situ formation, we studied with 2D hydrodynamical simulation using PLUTO whether planets can reach the observed orbits by planet migration in the circumbinary disc and how the disc influences the migration and the final orbit of circumbinary planets. We investigated the effects of viscosity and disc height, and found that the ability of a planet to open a gap in the disc is crucial for the successful migration. We found one simple model that can explain 6 out of the 10 orbits of the circumbinary planets and gets all of the considered planets closer to the observed position than the previous simulations.