English
Related papers

Related papers: Formation timescales for stellar bars in diverse g…

200 papers

In order to address the question of whether spiral disturbances in galaxy discs are gravitationally coupled to the halo, we conduct simulations of idealized models of disc galaxies. We compare growth rates of spiral instabilities in…

Astrophysics of Galaxies · Physics 2021-07-14 J. A. Sellwood

Bars in disk galaxies slow down as they transfer their angular momentum to their dark matter halo via dynamical friction from near-resonant orbits. This bar-halo dynamical friction can become ineffective once phase mixing erases the…

Astrophysics of Galaxies · Physics 2026-03-16 Rumi Kodama , Rimpei Chiba , Tetsuro Asano , Junichi Baba , Michiko Fujii

We use 25 simulated galaxies from the NIHAO project to define and characterize a variety of kinematic stellar structures: thin and thick discs, large scale single discs, classical and pseudo bulges, spheroids, inner discs, and stellar…

The strong time-dependence of the dynamics of galactic bars yields a complex and rapidly evolving distribution of dense gas and star forming regions. Although bars mainly host regions void of any star formation activity, their extremities…

Astrophysics of Galaxies · Physics 2015-10-28 F. Renaud , F. Bournaud , E. Emsellem , O. Agertz , E. Athanassoula , F. Combes , B. Elmegreen , K. Kraljic , F. Motte , R. Teyssier

The radial density profiles of stellar galaxy discs can be well approximated as an exponential. Compared to this canonical form, however, the profiles in the majority of disc galaxies show downward or upward breaks at large radii.…

(Abridge) Bars are very common in the centre of the disc galaxies, and they drive the evolution of their structure. A volume-limited sample of 2106 disc galaxies extracted from the Sloan Digital Sky Survey Data Release 5 was studied to…

Astrophysics of Galaxies · Physics 2009-11-13 J. A. L. Aguerri , J. Mendez-Abreu , E. M. Corsini

The arguments in favor of the unified formation mechanism for both slow (Lynden-Bell's) bars and common fast bars are given. This mechanism consists in a certain instability that is akin to the well-known radial orbit instability; it is…

Astrophysics · Physics 2007-05-23 E. V. Polyachenko , V. L. Polyachenko

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

A multi-faceted approach is described to constrain the importance of bar-driven evolution in disk galaxies, particularly bulge formation. N-body simulations are used to construct stellar kinematic bar diagnostics for edge-on systems and to…

Astrophysics · Physics 2016-01-27 M. Bureau , E. Athanassoula , A. Chung , G. Aronica

We examine the global stability of an exponential stellar disk embedded in a dark matter halo and constrain the mass-to-light ratio of observed disks in the I-band, Y_I. Assuming only that the radial surface density distribution of disks is…

Astrophysics · Physics 2007-05-23 D. Syer , Shude Mao , H. J. Mo

Isolated barred galaxies evolve by redistributing their internal angular momentum, which is emitted mainly at the inner disc resonances and absorbed mainly at the resonances in the outer disc and the halo. This causes the bar to grow…

Astrophysics · Physics 2007-05-23 E. Athanassoula

We study the growth of stellar discs of Milky Way-sized galaxies using a suite of cosmological simulations. We calculate the half-mass axis lengths and axis ratios of stellar populations split by age in isolated galaxies with stellar mass…

Astrophysics of Galaxies · Physics 2022-08-16 Xi Meng , Oleg Y. Gnedin

We investigate the formation and evolution of galactic disks immersed in assembling live DM halos. Disk/halo components have been evolved from the cosmological initial conditions and represent the collapse of an isolated density…

Astrophysics · Physics 2009-11-13 Clayton Heller , Isaac Shlosman , Lia Athanassoula

We present a study of large-scale bars in field and cluster environments out to redshifts of ~0.8 using a final sample of 945 moderately inclined disk galaxies drawn from the EDisCS project. We characterize bars and their host galaxies and…

Models of disc galaxies which invoke viscosity-driven radial flows have long been known to provide a natural explanation for the origin of stellar exponential discs, under the assumption that the star formation and viscous timescales are…

Astrophysics · Physics 2009-11-06 Annette Ferguson , Cathie Clarke

We investigate the coupling between the temporal variation from galaxy-formation feedback and the bar instability. We show that fluctuations from mass outflow on star-formation time scales affect the radial motion of disk orbits. The…

Astrophysics of Galaxies · Physics 2025-06-16 Martin D. Weinberg

The influence of central black holes on the dynamical evolution of bars in disk galaxies is examined. In particular, we use numerical simulation to estimate the minimum mass black hole (BH) needed to destroy a bar. Initially, bars form in…

Astrophysics · Physics 2007-05-23 Shunsuke Hozumi , Lars Hernquist

In this review, I discuss just three aspects of the stability and evolution of galactic discs. (1) I first review our understanding of the bar instability and how it can be controlled. Disc galaxies in which the orbital speed does not…

Astrophysics · Physics 2007-05-23 J. A. Sellwood

Aims. We aim to show how encounters with low-mass satellite galaxies may alter the bar formation in a Milky Way-like disc galaxy. Methods. We use high-resolution N-body simulations of a disc galaxy prone to mild bar instability. For…

Astrophysics of Galaxies · Physics 2017-08-16 R. Moetazedian , E. V. Polyachenko , P. Berczik , A. Just