中文
相关论文

相关论文: Local Stability of Galactic Discs in Modified Dyna…

200 篇论文

Accretion disks around stars, or other central massive bodies, can support long-lived, slowly precessing $m=1$ disturbances in which the fluid motion is nearly Keplerian with non-zero eccentricity. We study such `slow modes' in disks that…

地球与行星天体物理 · 物理学 2019-03-06 Wing-Kit Lee , Adam M. Dempsey , Yoram Lithwick

The stability of a rotating fluid disk to the formation of spiral arms is studied in the tightwinding approximation in the linear regime. The dispersion relation for spirals that was derived by Bertin et al. is shown to contain a new,…

天体物理学 · 物理学 2009-10-31 L. E. Montenegro , C. Yuan , B. G. Elmegreen

We show how the local approximation of astrophysical discs, which is the basis for the well known model of the shearing box, can be used to study many aspects of the dynamics of warped discs. In the local model, inclination of the orbit of…

太阳与恒星天体物理 · 物理学 2022-04-13 Gordon I. Ogilvie

Context. We consider a simple self-gravitating disk, made of two fluid components characterized by different effective thermal speeds and interacting with one another only through gravity; two-component models of this type have often been…

天体物理学 · 物理学 2009-11-11 Giuseppe Bertin , Antonio Cava

We make a revision of the stability criteria for equatorial circular orbits, obtained from the epicyclic approximation, which is widely used in Newtonian models for axisymmetric galaxies. We find that, for the case of thin disk models, the…

宇宙学与河外天体物理 · 物理学 2013-04-26 Ronaldo S. S. Vieira , Javier Ramos-Caro

Closely-packed multi-planet systems are known to experience dynamical instability if the spacings between the planets are too small. Such instability can be tempered by the frictional forces acting on the planets from gaseous discs. A…

地球与行星天体物理 · 物理学 2022-06-07 Jiaru Li , Laetitia Rodet , Dong Lai

In this letter we study the mean sizes of Halpha clumps in turbulent disk galaxies relative to kinematics, gas fractions, and Toomre Q. We use 100~pc resolution HST images, IFU kinematics, and gas fractions of a sample of rare, nearby…

We study gravitational instability and consequent star formation in a wide range of isolated disk galaxies, using three-dimensional, smoothed particle hydrodynamics simulations at resolution sufficient to fully resolve gravitational…

天体物理学 · 物理学 2009-11-10 Yuexing Li , Mordecai-Mark Mac Low , Ralf S. Klessen

We use simulations to study the growth of a pseudobulge in an isolated thin exponential stellar disc embedded in a static spherical halo. We observe a transition from later to earlier morphological types and an increase in bar prominence…

Protoplanetary disks often appear as multiple concentric rings in dust continuum emission maps and scattered light images. These features are often associated with possible young planets in these disks. Many non-planetary explanations have…

地球与行星天体物理 · 物理学 2018-01-24 C. P. Dullemond , A. B. T. Penzlin

In this paper we examine the issue of characterising the transport associated with gravitational instabilities in relatively cold discs, discussing in particular the conditions under which it can be described within a local, viscous…

天体物理学 · 物理学 2009-11-10 G. Lodato , W. K. M. Rice

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…

星系天体物理 · 物理学 2023-07-13 Sagar S. Goyary , Kanak Saha , H. Shanjit Singh , Suchira Sarkar

We revisit the diffusive instability in dusty disks that arises when the dust mass diffusivity and/or viscosity decreases sufficiently steeply with increasing dust density. Our updated model includes an incompressible, viscous gas that…

地球与行星天体物理 · 物理学 2026-02-19 Konstantin Gerbig , Min-Kai Lin

The equations describing the adiabatic, small radial oscillations of general relativistic stars are generalized to include the effects of a cosmological constant. The generalized eigenvalue equation for the normal modes is used to study the…

广义相对论与量子宇宙学 · 物理学 2007-05-23 C. G. Boehmer , T. Harko

We present a new systematic way of setting up galactic gas disks based on the assumption of detailed hydrodynamic equilibrium. To do this, we need to specify the density distribution and the velocity field which supports the disk. We first…

Star formation depends on the available gaseous "fuel" as well as galactic environment, with higher specific star formation rates where gas is predominantly molecular and where stellar (and dark matter) densities are higher. The partition…

宇宙学与河外天体物理 · 物理学 2015-05-20 Eve C. Ostriker

Non-linear evolution of the parametric instability of inertial waves inherent to eccentric discs is studied by way of a new local numerical model. Mode coupling of tidal deformation with the disc eccentricity is known to produce…

地球与行星天体物理 · 物理学 2018-05-02 Aaron F. Wienkers , Gordon I. Ogilvie

Hydrostatic equilibrium of the multiphase interstellar medium in the solar vicinity is reconsidered, with the regular and turbulent magnetic fields treated separately. The regular magnetic field strength required to support the gas is…

天体物理学 · 物理学 2009-11-06 Andrew Fletcher , Anvar Shukurov

The non-linear dynamics of bending instability and vertical structure of a galactic stellar disc embedded into a spherical halo are studied with N-body numerical modelling. Development of the bending instability in stellar galactic disc is…

宇宙学与河外天体物理 · 物理学 2015-05-19 A. Khoperskov , D. Bizyaev , N. Tiurina , M. Butenko

An accurate knowledge of the dark matter distribution in the Milky Way is of crucial importance for galaxy formation studies and current searches for particle dark matter. In this paper we set new dynamical constraints on the Galactic dark…

星系天体物理 · 物理学 2015-12-03 Miguel Pato , Fabio Iocco , Gianfranco Bertone