BibSonomy
CiteUlike
Connotea
Del.icio.us
Digg
Facebook
DOI: 10.1051/0004-6361:20053914
Disk eccentricity and embedded planets
W. Kley and G. DirksenInstitut für Astronomie & Astrophysik, Abt. Computational Physics, Universität Tübingen, Auf der Morgenstelle 10, 72076 Tübingen, Germany
e-mail: kley@tat.physik.uni-tuebingen.de
(Received 26 July 2005 / Accepted 11 October 2005)
Abstract
Aims.We investigate the response of an accretion disk to the
presence of a perturbing protoplanet embedded in the disk through time
dependent hydrodynamical simulations.
Methods.The disk is treated as a two-dimensional viscous fluid and the planet
is kept on a fixed orbit. We run a set of simulations
varying the planet mass, and the viscosity and temperature of the
disk. All runs are followed until they reach a quasi-equilibrium
state.
Results.We find that for planetary masses above a certain minimum mass,
already
for a viscosity of
, the disk
makes a transition from a nearly circular state into an
eccentric state. Increasing the planetary mass leads to a
saturation of disk eccentricity with a maximum value of around 0.25.
The transition to the eccentric state is driven by the excitation of
an m=2 spiral wave at the outer 1:3 Lindblad resonance. The effect
occurs only if the planetary mass is large enough to clear a
sufficiently wide and deep gap to reduce the damping effect of the
outer 1:2 Lindblad resonance. An increase in viscosity or
temperature in the disk, which both tend to close the gap, have an
adverse influence on the disk eccentricity.
Conclusions.In the eccentric state the mass accretion
rate onto the planet is greatly enhanced, an effect that may ease the
formation of massive planets beyond about 5
that are
otherwise difficult to reach.
Key words: accretion, accretion disks -- hydrodynamics -- planets and satellites: formation
SIMBAD Objects
© ESO 2006