RODEO: a new method for planet-disk interaction

Aims. In this paper we describe a new method for studying the hydrodynamical problem of a planet embedded in a gaseous disk. Methods. We use a finite volume method with an approximate Riemann solver ( the Roe solver), together with a special way to integrate the source terms. This new source term integration scheme sheds new light on the Coriolis instability, and we show that our method does not suffer from this instability. Results. The first results on flow structure and gap formation are presented, as well as accretion and migration rates. For Mp < 0.1 M-J and M-p > 1.0 M-J (M-J = Jupiter's mass) the accretion rates do not depend sensitively on numerical parameters, and we find that within the disk's lifetime a planet can grow to 3-4 M-J. In between these two limits numerics play a major role, leading to differences of more than 50% for different numerical parameters. Migration rates are not affected by numerics at all as long as the mass inside the Roche lobe is not considered. We can reproduce the type I and type II migration for low-mass and high-mass planets, respectively, and the fastest moving planet of 0.1 M-J has a migration time of only 2.0 x 10(4) yr.