4:30 PM - 4:45 PM
[PPS08-29] Circumbinary Planet's Orbital Evolution in a Dissipating Protoplanetary Disk
Keywords:Circumbinary planet, Protoplanetary disk, Migration
We carried out N-body simulations for binary systems with eccentricity, mass ratio, and planet mass as parameters to examine the scenario. We found our scenario can reproduce the present circumbinary planets' orbits those locate just outside the unstable region. Planets tend to survive the orbital evolution more likely in less eccentric binary systems with ebin<0.2. Most of binary systems hosting a circumbinary planet have eccentricities ebin≦0.16, which is consistent with our results. Planet mass dependence is also examined for range from 0.0056MJ to 1.7MJ. Surviving rate was high for planets in mass range from 0.01MJ to 0.32MJ. Gas drag force is too weak for planets smaller than 0.01MJ to damp the orbital excitations. On the other hand, gas drag is too strong for planets larger than 0.32MJ so that the planets' orbits are not excited enough to push them outside the unstable region. Our results give constraints on mass and semimajor axis of circumbinary planets as well as eccentricity and mass ratio of the host binary.