相关论文: Tidal Torques and Galactic Warps

Accretion discs are present around both stellar-mass black holes in X-ray binaries and supermassive black holes in active galactic nuclei. A wide variety of circumstantial evidence implies that many of these discs are warped. The standard…

We report results of the first global three-dimensional magnetohydrodynamic simulations of the waves excited in an accretion disc by a rotating star with a dipole magnetic field misaligned from the star's rotation axis (which is aligned…

A substantial fraction of the warps in spiral galaxies may result from bending instabilities if the disks are essentially self-gravitating. With N-body simulations, we show that galaxies with self-gravitating disks as thick as HI disks are…

N-body simulations show that when infall reorientates the outer parts of a galactic halo by several degrees per Gyr, a self-gravitating disk that is embedded in the halo develops an integral-sign warp that is comparable in amplitude to…

We model the motion of a small compact object on a nearly circular orbit around a spinning supermassive black hole, which is also interacting with a thin equatorial accretion-disk surrounding the latter, through tools from self-force and…

High-resolution, 2-D hydrodynamical simulations with a large dynamic range are performed to study the turbulent nature of the interstellar medium (ISM) in galactic disks. The simulations are global, where the self-gravity of the ISM,…

We analyze the linear, 3D response to tidal forcing of a disk that is thin and thermally stratified in the direction normal to the disk plane. We model the vertical disk structure locally as a polytrope which represents a disk of high…

We calculate tidal torque due to semi-diurnal thermal tides in rotating hot Jupiters, taking account of the effects of radiative cooling in the envelope and of the planets rotation on the tidal responses. We use a simple Jovian model…

[Abridged] The tidal torque exerted by a protoplanetary disk with power law surface density and temperature profiles onto an embedded protoplanetary embryo is generally a negative quantity that leads to the embryo inwards migration. Here we…

Accretion discs around black holes can become warped by Lense-Thirring precession if the disc is tilted with respect to the black hole spin vector. When the disc viscosity is sufficiently large that warp propagation is diffusive, the inner…

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…

A geometrically thin, optically thick, warped accretion disk with a central source of luminosity is subject to non-axisymmetric forces due to radiation pressure; the resulting torque acts to modify the warp. Initially planar accretion disks…

We consider the angular momentum exchange at the corotation resonance between a two-dimensional gaseous disk and a uniformly rotating external potential, assuming that the disk flow is adiabatic. We first consider the linear case for an…

A self-gravitating, differentially rotating galactic disc under vertical hydrostatic equilibrium is supported by the vertical pressure gradient force against the gravitational collapse. Such discs are known to support various bending modes…

We evaluate the torque acting on a gravitational perturber on a retrograde circular orbit in the midplane of a gaseous disk. We assume that the mass of this satellite is so low it weakly disturbs the disk (type I migration). The perturber…

A geometrically thin, optically thick, warped accretion disk with a central source of luminosity is subject to non-axisymmetric forces due to radiation pressure; the resulting torque acts to modify the warp. In a recent paper, \cite{pri96}…

Circumbinary discs (CBDs) arise in many astrophysical settings, including young stellar binaries and supermassive black hole binaries. Their structure is mediated by gravitational torques exerted on the disc by the central binary. The…

The presence of radial truncations in stellar disks is reviewed. There is ample evidence that many disk galaxies have relatively shaprt truncations in their disks. These often are symmetric and independent of the wavelength band of the…

We present a pseudo-Newtonian stationary circumbinary slim disk model. We extend the slim disk formalism by including the binary tidal torque and solve the resulting steady-state equations to determine the circumbinary disk structure. We…

The maximum ratio of the tangential force to the mean background radial force is a useful quantitative measure of the strength of nonaxisymmetric perturbations in disk galaxies. Here we consider the distribution of this ratio, called Qg,…