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Related papers: Generalised warped disk equations

200 papers

We present solutions to the relativistic thin disc evolutionary equation using a modified description of the mean fluid flow within the disc. The model takes into account the effects of sub-circular velocities in the innermost disc regions,…

High Energy Astrophysical Phenomena · Physics 2019-08-14 Andrew Mummery , Steven A. Balbus

We present new sub-arcsecond (0.7'') Combined Array for Research in Millimeter-wave Astronomy (CARMA) observations of the 1.3 mm continuum emission from circumstellar disks around 11 low and intermediate mass pre-main sequence stars. High…

Solar and Stellar Astrophysics · Physics 2009-07-24 Andrea Isella , John M. Carpenter , Anneila I. Sargent

The standard equilibrium for radiation-dominated accretion disks has long been known to be viscously, thermally, and convectively unstable, but the nonlinear development of these instabilities---hence the actual state of such disks---has…

Astrophysics · Physics 2009-11-06 Eric Agol , Julian Krolik , Neal Turner , James Stone

We explore the evolution of the eccentricity of an accretion disc perturbed by an embedded planet whose mass is sufficient to open a large gap in the disc. Various methods for representing the orbit-averaged motion of an eccentric disc are…

Earth and Planetary Astrophysics · Physics 2017-03-29 Jean Teyssandier , Gordon I. Ogilvie

We present numerical simulations of misaligned discs around a spinning black hole covering a range of parameters. Previous simulations have shown that discs that are strongly warped by a forced precession -- in this case the Lense-Thirring…

High Energy Astrophysical Phenomena · Physics 2021-03-24 Anagha Raj , Chris Nixon , Suzan Dogan

We analyze gravitational waves propagating in an isotropic cosmic fluid endowed with a bulk viscosity $\zeta$ and a shear viscosity $\eta$, assuming these coefficients to vary with fluid density $\rho$ as $\rho^\lambda$, with $\lambda=1/2$…

General Relativity and Quantum Cosmology · Physics 2019-07-16 Iver Brevik , Shin'ichi Nojiri

Circumbinary accretion occurs throughout the universe, from the formation of stars and planets to the aftermath of major galactic mergers. We present an extensive investigation of circumbinary accretion disks, studying circular binaries…

Astrophysics of Galaxies · Physics 2023-10-13 Alexander J. Dittmann , Geoffrey Ryan

Numerical, two-dimensional, time-dependent hydrodynamical models of geometrically thick accretion discs around black holes are presented. Accretion flows with non-effective radiation cooling (ADAFs) can be both convectively stable or…

Astrophysics · Physics 2009-09-25 Igor V. Igumenshchev

Thin viscous Keplerian accretion disks are considered asymptotically stable, even though they can show significant dynamic activity on short timescales. In this paper the dynamics of non-axisymmetric hydrodynamical disturbances of disks are…

High Energy Astrophysical Phenomena · Physics 2015-05-13 Paola Rebusco , Orkan M. Umurhan , Wlodek Kluzniak , Oded Regev

We have studied the structure of hot accretion flow bathed in a general large-scale magnetic field. We have considered magnetic parameters $ \beta_{r,\varphi,z}[=c^2_{r,\varphi,z}/(2c^2_{s})] $, where $ c^2_{r, \varphi, z} $ are the…

Astrophysics of Galaxies · Physics 2015-06-05 S. Abbassi , A. Mosallanezhad

When a galaxy forms, the disk may initially be tilted with respect to a flattened dark halo. The misalignment between the disk and the halo is a common explanation for galactic disk warps, since in this state, disks have precessing bending…

Astrophysics · Physics 2009-10-22 John Dubinski , Konrad Kuijken

It is quite likely that self-gravity will play an important role in the evolution of accretion discs, in particular those around young stars, and those around supermassive black holes. We summarise, here, our current understanding of the…

Solar and Stellar Astrophysics · Physics 2016-04-13 Ken Rice

The model of a geometrically thin gaseous disk in the external gravitational potential is considered. The dinamics of small nonaxisymmetric perturbations in the plane of the accretion disk with dissipative effects is investigated. It is…

Astrophysics · Physics 2009-10-30 A. V. Khoperskov , S. S. Khrapov

We consider a geometrically thin, Keplerian disk in the orbital plane of a binary black hole (BHBH) consisting of a spinning primary and low-mass secondary (mass ratio q < 1). To account for the principle effects of general relativity (GR),…

High Energy Astrophysical Phenomena · Physics 2013-06-18 Stuart L. Shapiro

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…

Solar and Stellar Astrophysics · Physics 2013-03-20 M. M. Romanova , G. V. Ustyugova , A. V. Koldoba , R. V. E. Lovelace

We carry out three-dimensional, high resolution (up to $1024^2\times 256$) hydrodynamic simulations of the evolution of vortices in vertically unstratified Keplerian disks using the shearing sheet approximation. The transient amplification…

Astrophysics · Physics 2011-02-11 Yue Shen , James M. Stone , Thomas A. Gardiner , ;

We determine the evolution of a giant planet-disk system that orbits a member of a binary star system and is mildly inclined with respect to the binary orbital plane. The planet orbit and disk are initially mutually coplanar. We analyze the…

Earth and Planetary Astrophysics · Physics 2016-01-27 Stephen H. Lubow , Rebecca G. Martin

We study the persistence of warps in galactic discs in the presence of massive halos. A disc is approximated by a set of massive rings, while a halo is represented by a conventional n-body simulation. We confirm the conclusion of Nelson &…

Astrophysics · Physics 2009-10-30 James Binney , Ing-Guey Jiang , Suvendra Dutta

Observations of protoplanetary disks show that some characteristics seem recurrent, even in star formation regions that are physically distant such as surface mass density profiles varying as $r^{-1}$, or aspect ratios about 0.03 to 0.23.…

Earth and Planetary Astrophysics · Physics 2015-03-12 Kévin Baillié , Sébastien Charnoz