On the Interaction between a Protoplanetary Disk and a Planet in an Eccentric Orbit: Application of Dynamical Friction

Understand

We present a new analytic approach to the disk-planet interaction that is especially useful for planets with eccentricity larger than the disk aspect ratio.

• We make use of the dynamical friction formula to calculate the force exerted on the planet by the disk, and the force is averaged over the period of the planet.
• The resulting migration and eccentricity damping timescale agrees very well with the previous works in which the planet eccentricity is moderately larger than the disk aspect ratio.
• The advantage of this approach is that it is possible to apply this formulation to arbitrary large eccentricity.