On the interaction between embedded planets and the corotation region of protoplanetary discs
Abstract
Disc material in the corotation region librates with respect to low-mass planets
on horseshoe trajectories. The exchange of angular momentum associated
with this libration gives rise to the non-linear corotation torque (the horseshoe
drag). For the first project described herein, we ran a suite of high-resolution
2D hydrodynamic simulations of low-mass (5 Earth mass) planets, at eccentricities
0 e < 0.3, embedded in both viscous protoplanetary discs with
entropy relaxation and inviscid discs without. The attenuation of the corotation
torque was obtained from these simulations and found to be well-fitted by
an exponential decay with a characteristic ‘e-folding eccentricity’ that scales
linearly with disc scale height. These results were tested with different disc
scale heights between 0.03 and 0.1 and with a 10 Earth mass planet.
In the second project in this thesis we sought to extend on these results by
examining the case of an embedded 5 Earth mass planet in three dimensional
discs. We found that our scaling relation held in this new case, confirming
that it is possible to use 2D simulations with a softening parameter to capture
the behaviour of the corotation torque. We investigated the time-averaged
horseshoe width as a function of altitude and found that the corotation region
extends from the midplane to around three scale heights, changing most near
the midplane for eccentric planets.
The final project looked at 3D radiative discs, under the influence of stellar
irradiation, with more massive embedded planets capable of triggering gap formation.
We use the pluto code to simulate a Jupiter mass planet at 5 AU in
a protoplanetary disc. We describe our progress in understanding the process
of gap formation in a case study of this class of hitherto undescribed disc.
Authors
Fendyke, StephenCollections
- Theses [4143]