Related papers: On the corotation torque in a radiatively ineffici…
Cold optically thick accretion disks with hot coronae and radial advection have been investigated. Within the framework of $\alpha$-viscosity models, we assume that all the mass accretion and angular momentum transport take place in the…
Many accretion discs are thought to be warped. Recent hydrodynamical simulations show that (i) discs can break into distinct planes when the amplitude of an imposed warp is sufficiently high and the viscosity sufficiently low, and that (ii)…
In paper I, we have studied the conditions under which flux tubes are expelled from adiabatic thick accretion disks. In the present paper, we explore a few other models of thick disks, where flux tubes could be stored. We show that flux…
During early phases of a protoplanetary disks's life, gravitational instabilities can produce significant mass transport, can dramatically alter disk structure, can mix and shock-process gas and solids, and may be instrumental in planet…
In order to reproduce the statistical properties of the observed exoplanets, population synthesis models have shown that the migration of protoplanets should be significantly slowed down, and that processes stalling migration should be at…
The stratification of entropy and the stratification of angular momentum are closely analogous. Of particular interest is the behavior of disks in which angular momentum transport is controlled by convection, and heat transport by dynamical…
We report on laboratory experiments of wave-driven rotating turbulence. A set of wavemakers produces inertial-wave beams that interact nonlinearly in the central region of a water tank mounted on a rotating platform. The forcing thus…
This paper explores the driving of low-level hydrodynamical activity in protoplanetary-disc dead zones. A small adverse radial entropy gradient, ordinarily stabilised by rotation, excites oscillatory convection (`convective overstability')…
We study the time evolution of two protoplanets still embedded in a protoplanetary disk. The results of two different numerical approaches are presented and compared. In the first approach, the motion of the disk material is computed with…
We perform numerical simulations of solid particle motion in a shearing box model of a protoplanetary disc. The accretion flow is turbulent due to the action of the magnetorotational instability. Aerodynamic drag on the particles is…
We present the results of three-dimensional global magnetohydrodynamic (MHD) simulations of the Parker-shearing instability in a differentially rotating torus initially threaded by toroidal magnetic fields. An equilibrium model of…
We examine the linear stability of a flow threaded by a weak, vertical magnetic field in a disk with a keplerian rotation profile and a vertical stratification of the ionization degree as that predicted for vast portions of protoplanetary…
We present two-dimensional hydrodynamical simulations of pairs of planets migrating simultaneously in the Type I regime in a protoplanetary disc. Convergent migration naturally leads to the trapping of these planets in mean-motion…
Empirical evidence of planets in gas-rich circumstellar discs is required to constrain giant planet formation theories. Here we study the kinematic patterns which arise from planet-disc interactions and their observability in CO rotational…
The non-linear hydrodynamic stability of thin, compressible, Keplerian disks is studied on the large two-dimensional compressible scale, using a high-order accuracy spectral method. We show that purely hydrodynamic perturbations, while…
A certain appeal to the alpha model for turbulence and related viscosity in accretion disks was that one scales the Reynolds stresses simply on the thermal pressure, assuming that turbulence driven by a certain mechanism will attain a…
We extend previous studies of the tidal truncation of coplanar disks in binary systems to the more general case of noncoplanar disks. As in the prograde coplanar case, Lindblad resonances play a key role in tidal truncation. We analyze the…
Solar radiation pressure can have a substantial long-term effect on the orbits of high area-to-mass ratio spacecraft, such as solar sails. We present a study of the coupling between radiation pressure and the gravitational perturbation due…
We review results on the dynamics of warped gaseous discs. We consider tidal perturbation of a Keplerian disc by a companion star orbiting in a plane inclined to the disc. The perturbation induces the precession of the disc, and thus of any…
We calculate small amplitude gravitational and thermal tides of uniformly rotating hot Jupiters composed of a nearly isentropic convective core and a geometrically thin radiative envelope. We treat the fluid in the convective core as a…