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Related papers: Spiral waves in accretion discs - theory

200 papers

Spiral waves are striking self-organized coherent structures that organize spatio-temporal dynamics in dissipative, spatially extended systems. In this paper, we provide a conceptual approach to various properties of spiral waves. Rather…

Pattern Formation and Solitons · Physics 2021-02-09 Björn Sandstede , Arnd Scheel

We have performed three-dimensional numerical simulations of accretion discs in a close binary system using the Smoothed Particle Hydrodynamics method. Our result show that, contrary to previous claims, 3D discs do exist even when the…

Astrophysics · Physics 2009-09-25 Hiroshi Yukawa , Henri M. J. Boffin , Takuya Matsuda

I review, from an observational perspective, the interactions of accretion discs with magnetic fields in cataclysmic variable stars. I start with systems where the accretion flows via a stream, and discuss the circumstances in which the…

Astrophysics · Physics 2009-11-13 Coel Hellier

Can the present dynamics of spiral galaxies tell us something about the merging history, the formation and evolution of disks? Galaxy interactions thicken or destroy disks; the simultaneous presence of thick and thin disks is a tracer of…

Astrophysics · Physics 2007-05-23 F. Combes

The dynamics of pseudo-classical spinning particles in spacetime of gravitational plane waves of general polarization and harmonic profile is studied. The resulting equations of motion are solved exactly and the results are compared with…

General Relativity and Quantum Cosmology · Physics 2015-06-25 Morteza Mohseni

The polarization of electromagnetic waves in the presence of a gravitational wave is analyzed. The rotation of the polarization angle and the Stokes parameters are deduced. A possible application to the detection of stochastic background of…

General Relativity and Quantum Cosmology · Physics 2016-02-03 Shahen Hacyan

We examine the properties of spiral shocks from a steady, adiabatic, non-axisymmetric accretion disk around a compact star in binary. We first time incorporate all the possible influences from binary through adopting the Roche potential and…

High Energy Astrophysical Phenomena · Physics 2021-12-08 Ramiz Aktar , Li Xue , Tong Liu

The density-wave theory of spiral structure proposes that star formation occurs in or near a spiral-shaped region of higher density that rotates rigidly within the galactic disk at a fixed pattern speed. In most interpretations of this…

We have recently shown that spiral density waves propagating in accretion disks can undergo a parametric instability by resonantly coupling with and transferring energy into pairs of inertial waves (or inertial-gravity waves when buoyancy…

Earth and Planetary Astrophysics · Physics 2016-12-21 Jaehan Bae , Richard P. Nelson , Lee Hartmann

We present results from the first global 3D MHD simulations of accretion disks in Cataclysmic Variable (CV) systems in order to investigate the relative importance of angular momentum transport via turbulence driven by the magnetorotational…

Solar and Stellar Astrophysics · Physics 2016-06-01 Wenhua Ju , James M. Stone , Zhaohuan Zhu

A scroll wave in a very thin layer of excitable medium is similar to a spiral wave, but its behaviour is affected by the layer geometry. We identify the effect of sharp variations of the layer thickness, which is separate from filament…

Pattern Formation and Solitons · Physics 2015-02-13 I. V. Biktasheva , H. Dierckx , V. N. Biktashev

We present results from a suite of three-dimensional global hydrodynamic simulations which show that spiral density waves propagating in circumstellar disks are unstable to the growth of a parametric instability that leads to break-down of…

Earth and Planetary Astrophysics · Physics 2016-09-21 Jaehan Bae , Richard P. Nelson , Lee Hartmann , Samuel Richard

We present the first local simulations of disc breaking/tearing in a warped accretion disc. Warps can arise due to a misalignment between the disc and the rotation axis of the central object, or a misalignment with the orbital plane of a…

Solar and Stellar Astrophysics · Physics 2026-02-25 Loren E Held , Gordon I. Ogilvie

Understanding how accretion proceeds in proto-planetary discs and more generally their dynamics is a crucial issue for explaining the conditions in which planets form. The role that accretion of gas from the surrounding molecular cloud onto…

Astrophysics of Galaxies · Physics 2017-03-15 Patrick Hennebelle , Geoffroy Lesur , Sébastien Fromang

Spiral waves arise in many biological, chemical, and physiological systems. The kinematical model can be used to describe the motion of the spiral arms approximated as curves in the plane. For this model, there appeared some results in the…

Dynamical Systems · Mathematics 2007-05-23 Chu-Pin Lo , Nedialko S. Nedialkov , Juan-Ming Yuan

We present the results of two-dimensional numerical simulations of stellar galactic disks, aimed at studying the non-linear coupling between bar and spiral waves and modes, in disks with realistically peaked rotation profiles. The power…

Astrophysics · Physics 2011-05-23 F. Masset , M. Tagger

The arising of turbulence in gas-dynamic (non-magnetic) accretion disks is a major issue of modern astrophysics. Such accretion disks should be stable against the turbulence generation, in contradiction to observations. Searching for…

Solar and Stellar Astrophysics · Physics 2014-10-01 E. P. Kurbatov , D. V. Bisikalo , P. V. Kaygorodov

Shock wave theory was first studied for gas dynamics, for which shocks appear as compression waves. A shock wave is characterized as a sharp transition, even discontinuity in the flow. In fact, shocks appear in many different physical…

Analysis of PDEs · Mathematics 2007-05-23 Tai-Ping Liu

We study particle dynamics in local two-dimensional simulations of self-gravitating accretion discs with a simple cooling law. It is well known that the structure which arises in the gaseous component of the disc due to a gravitational…

Earth and Planetary Astrophysics · Physics 2015-06-05 P. G. Gibbons , W. K. M. Rice , G. R. Mamatsashvili

Spiral arms have been observed in nearly a dozen protoplanetary discs in near-infrared scattered light and recently also in the sub-millimetre continuum. While one of the most compelling explanations is that they are driven by planetary or…

Earth and Planetary Astrophysics · Physics 2017-12-27 Attila Juhasz , Giovanni P. Rosotti