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Related papers: Bar instability in disk-halo systems

200 papers

Using high resolution N-body simulations of stellar disks embedded in cosmologically motivated dark matter halos, we study the evolution of bars and the transfer of angular momentum between halos and bars. We find that dynamical friction…

Astrophysics · Physics 2009-11-07 Octavio Valenzuela , Anatoly Klypin

I review the arguments for the importance of halo structure in driving galaxy evolution and coupling a galaxy to its environment. We begin with a general discussion of the key dynamics and examples of structure dominated by modes. We find…

Astrophysics · Physics 2007-05-23 Martin D. Weinberg

We examine the bar instability in models with an exponential disk and a cuspy NFW-like dark matter (DM) halo inspired by cosmological simulations. Bar evolution is studied as a function of numerical resolution in a sequence of models…

Astrophysics · Physics 2015-05-13 John Dubinski , Ingo Berentzen , Isaac Shlosman

N-body simulations argue that the inner haloes of barred galaxies should not be spherical, nor even axisymmetric, but triaxial. The departure from sphericity is strongest near the centre and decreases outwards; typical axial ratios for the…

Astrophysics · Physics 2008-11-26 E. Athanassoula

We conduct numerical experiments by evolving gaseous/stellar disks embedded in live dark matter halos aiming at quantifying the effect of gas spatial resolution and gas content on the bar evolution. Model sequences have been constructed…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Jorge Villa-Vargas , Isaac Shlosman , Clayton Heller

Self-consistent bars that form in galaxies embedded within cuspy halos are unable to flatten the cusp. Short bars form in models with quasi-flat rotation curves. They lose angular momentum to the halo through dynamical friction, but the…

Astrophysics · Physics 2009-11-07 J. A. Sellwood

We demonstrate that, due to their low surface mass density and large dark matter content, LSB disks are quite stable against the growth of global bar modes. However, they may be only marginally stable against local disk instabilities. We…

Astrophysics · Physics 2009-10-28 Chris Mihos , Stacy McGaugh , Erwin de Blok

Most of the visible mass in a typical spiral galaxy is distributed in a thin disk, with a radial extent much larger than its thickness. While the planar disk structure, including non-axisymmetric features such as spiral structure, has been…

Astrophysics of Galaxies · Physics 2025-07-04 Chanda J. Jog

A strong bar rotating within a massive halo should lose angular momentum to the halo through dynamical friction, as predicted by Weinberg. We have conducted fully self-consistent, numerical simulations of barred galaxy models with a live…

Astrophysics · Physics 2015-06-24 J. A. Sellwood , Victor P. Debattista

While bars are common in disk galaxies, their formation conditions are not well understood. We use $N$-body simulations to study bar formation and evolution in isolated galaxies consisting of a stellar disk, a classical bulge, and a dark…

Astrophysics of Galaxies · Physics 2023-01-25 Dajeong Jang , Woong-Tae Kim

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…

The predicted central densities of dark matter halos in LCDM models exceed those observed in some galaxies. Weinberg & Katz argue that angular momentum transfer from a rotating bar in the baryonic disk can lower the halo density, but they…

Astrophysics · Physics 2009-11-11 J. A. Sellwood

We carry out a detailed orbit analysis of gravitational potentials selected at different times from an evolving self-consistent model galaxy consisting of a two-component disk (stars+gas) and a live halo. The results are compared with a…

Astrophysics · Physics 2009-10-30 I. Berentzen , C. H. Heller , I. Shlosman , K. J. Fricke

A theory is developed for the dynamics of eccentric perturbations $[\propto \exp(\pm i\phi)]$ of a disk galaxy residing in a spherical dark matter halo and including a spherical bulge component. The disk is represented as a large number $N$…

Astrophysics · Physics 2009-10-31 R. V. E. Lovelace , L. Zhang , D. A. Kornreich , M. P. Haynes

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…

Astrophysics of Galaxies · Physics 2023-07-13 Sagar S. Goyary , Kanak Saha , H. Shanjit Singh , Suchira Sarkar

The evolution of a stellar bar transforms not only the galactic disk, but also the host dark matter halo. We present high resolution, fully self-consistent N-body simulations that clearly demonstrate that dark matter halo central density…

Astrophysics · Physics 2009-11-10 Kelly Holley-Bockelmann , Martin Weinberg , Neal Katz

We employ an improved methodology to insert live stellar disks into high-resolution dark matter simulations of Milky Way sized halos, allowing us to investigate the fate of thin stellar disks in the tumultuous environment of cold dark…

Astrophysics of Galaxies · Physics 2015-07-15 Denis Yurin , Volker Springel

Using analytic stability criteria, we demonstrate that, due to their low surface mass density and large dark matter content, LSB disks are quite stable against the growth of global nonaxisymmetric modes such as bars. However, depending on…

Astrophysics · Physics 2007-05-23 Chris Mihos , Stacy McGaugh , Erwin de Blok

We investigate the effect of rotating, triaxial halos on disk galaxies through an extensive set of numerical N-body simulations. Our simulations use a rigid potential field for the halos and bulges and collisionless particles for the disks.…

Astrophysics · Physics 2007-05-23 Jeremy L. Tinker , Barbara S. Ryden

Evolution of stellar bars in disk galaxies is accompanied by dynamical instabilities and secular changes. Following the vertical buckling instability, the bars are known to weaken dramatically and develop a pronounced boxy/peanut shape when…

Astrophysics · Physics 2009-11-13 Inma Martinez-Valpuesta , Isaac Shlosman , Clayton Heller