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Related papers: Counter-Rotating Accretion Discs

200 papers

The dynamical stability and evolution of disc galaxies with different disc thickness as well as various fraction and concentration of stellar counter-rotation is investigated with self-consistent numerical simulations. In particular,…

Astrophysics · Physics 2007-05-23 D. Friedli

We investigate the thermal stability of the outer layers of accretion discs in which the local viscous energy dissipation rate scales with the pressure as for standard Shakura-Sunyaev discs. By solving for the accretion disc vertical…

Astrophysics · Physics 2009-10-31 Martijn de Kool , Dayal T. Wickramasinghe

Migration commonly occurs during the epoch of planet formation. For emerging gas giant planets, it proceeds concurrently with their growth through the accretion of gas from their natal protoplanetary disks. Similar migration process should…

Earth and Planetary Astrophysics · Physics 2024-06-19 Ya-Ping Li , Yi-Xian Chen , Douglas N. C. Lin

We show that the distribution of observed accretion rates is a powerful diagnostic of protoplanetary disc physics. Accretion due to turbulent ("viscous") transport of angular momentum results in a fundamentally different distribution of…

Solar and Stellar Astrophysics · Physics 2023-07-12 R. Alexander , G. Rosotti , P. J. Armitage , G. J. Herczeg , C. F. Manara , B. Tabone

In Montgomery (2009a), we show that accretion discs in binary systems could retrogradely precess by tidal torques like the Moon and the Sun on a tilted, spinning, non-spherical Earth. In addition, we show that the state of matter and the…

Solar and Stellar Astrophysics · Physics 2015-05-20 M. M. Montgomery , D. V. Bisikalo

A self-consistent solution for a thin accretion disk with turbulent convection is presented. The disk viscosity and the convective flux are derived from a physical model for turbulence, and expressed in terms of the local physical…

Astrophysics · Physics 2009-10-28 Itzhak Goldman , Amri Wandel

Accretion disks whose matter follows eccentric orbits can arise in multiple astrophysical situations. Unlike circular orbit disks, the vertical gravity in eccentric disks varies around the orbit. In this paper, we investigate some of the…

High Energy Astrophysical Phenomena · Physics 2021-11-03 Taeho Ryu , Julian Krolik , Tsvi Piran

Precessing accretion discs have long been suggested as explanations for the long periods observed in a variety of X-ray binaries, most notably Her X-1/HZ Her. We show that an instability of the disc's response to the radiation reaction…

Astrophysics · Physics 2009-10-31 Ralph A. M. J. Wijers , J. E. Pringle

Like their lower mass siblings, massive protostars can be expected to: a) be surrounded by circumstellar disks and b) launch magnetically-driven jets and outflows. The disk formation and global evolution is thereby controlled by advection…

Solar and Stellar Astrophysics · Physics 2023-01-18 André Oliva , Rolf Kuiper

We investigate whether a circumbinary gas disc can coalesce a supermassive black hole binary system in the centre of a galaxy. This is known to be problematic for a prograde disc. We show that in contrast, interaction with a retrograde…

High Energy Astrophysical Phenomena · Physics 2015-05-20 C. J. Nixon , P. J. Cossins , A. R. King , J. E. Pringle

We present the results of qualitative consideration of possible changes occurring during the transition from the hot accretion disc to the cool one. We argue the possible existence of one more type of spiral density waves in the inner part…

Astrophysics · Physics 2009-11-10 D. V. Bisikalo , A. A. Boyarchuk , P. V. Kaygorodov , O. A. Kuznetsov , T. Matsuda

Straight-forward models of X-ray reflection in the inner region of accretion discs predict that primary X-ray flux and the flux reflected off the surface of the disc should vary together, albeit a short light travel time delay. Most of the…

Astrophysics · Physics 2008-11-26 Sergei Nayakshin

In this paper we explore numerically the evolution of a warped accretion disc. Here, we focus here on the regime where the warp evolves diffusively. By comparing the numerical results to a simple diffusion model, we are able to determine…

Astrophysics · Physics 2009-11-13 Giuseppe Lodato , J. E. Pringle

Circumplanetary disks can be found around forming giant planets, regardless of whether core accretion or gravitational instability built the planet. We carried out state-of-the-art hydrodynamical simulations of the circumplanetary disks for…

Earth and Planetary Astrophysics · Physics 2016-12-07 J. Szulágyi , L. Mayer , T. Quinn

We investigate the linear tidal perturbation of a viscous Keplerian disk by a companion star orbiting in a plane inclined to the disk. We consider m=1 perturbations with odd symmetry with respect to the z=0 midplane. Since the response of a…

Astrophysics · Physics 2009-10-31 Caroline E. J. M. L. J. Terquem

Rotating transonic flows are long known to admit standing or oscillating shocks and that the excess thermal energy in the post shock flow drives a part of the infalling matter as bipolar outflows. We compute massloss from a viscous…

Astrophysics · Physics 2008-11-26 Indranil Chattopadhyay , Santabrata Das

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

This paper explores the effects of large-scale magnetic fields in hot accretion flows for asymmetric configurations with respect to the equatorial plane. The solutions that we have found show that the large-scale asymmetric magnetic field…

High Energy Astrophysical Phenomena · Physics 2017-07-26 Maryam Samadi , Shahram Abbassi , Richard Lovelace

One of the greatest issues in modelling black hole fuelling is our lack of understanding of the processes by which gas loses angular momentum and falls from galactic scales down to the nuclear region where an accretion disc forms,…

Astrophysics of Galaxies · Physics 2013-12-24 Juan Manuel Carmona-Loaiza , Monica Colpi , Massimo Dotti , Riccardo Valdarnini

The detection of significant concentrations of crystalline silicates in comets indicates an extensive radial mixing in the primordial solar nebula. In studying the radial transport of matter within protoplanetary disks by numerical model…

Astrophysics · Physics 2008-04-22 Michael Wehrstedt , Hans-Peter Gail