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Related papers: Bar Formation from Galaxy Flybys

200 papers

We study evolution of galactic bars using suite of very high-resolution zoom-in cosmological simulations of galaxies at z ~ 9-2. Our models were chosen to lie within similar mass DM halos, log(Mvir/Mo) ~ 11.65 +- 0.05, at z=6, 4, and 2, in…

Astrophysics of Galaxies · Physics 2022-08-03 Da Bi , Isaac Shlosman , Emilio Romano-Diaz

Bars in galaxies may form not only through instability, but also as a result of an interaction with another galaxy. In particular, they may appear in disky dwarf galaxies interacting with Milky Way-like galaxies. Here we report the results…

Astrophysics of Galaxies · Physics 2018-11-29 Grzegorz Gajda , Ewa L. Łokas , E. Athanassoula

From this vast subject, I will pick out and review three specific topics, namely the formation and evolution of bars, the formation of bulges, and the evolution during multiple major mergers. Bars form naturally in galactic discs. Their…

Astrophysics · Physics 2009-11-13 E. Athanassoula

Bars, a common and important structure in disk galaxies, can be induced by galaxy interactions. Although there have been some studies on bar formation in flybys or collisions, the vast parameter space still leaves many scenarios that…

Astrophysics of Galaxies · Physics 2025-07-09 Yufan Fane Zhou , Zhiyuan Li , Hui Li

We review the role of stellar flybys and encounters in shaping planet-forming discs around young stars, based on the published literature on this topic in the last 30 years. Since most stars $\leq~2$ Myr old harbour protoplanetary discs,…

Earth and Planetary Astrophysics · Physics 2022-12-23 Nicolás Cuello , François Ménard , Daniel J. Price

Gravitational interactions and mergers are shaping and reshaping galaxies throughout the observable universe. While observations of interacting galaxies at low redshifts yield detailed information about the processes at work, observations…

Astrophysics · Physics 2009-10-31 Francois Schweizer

We use N-body simulations of bar formation in isolated galaxies to study the effect of bulge mass and bulge concentration on bar formation. Bars are global disk instabilities that evolve by transferring angular momentum from the inner to…

Astrophysics of Galaxies · Physics 2018-01-03 Sandeep Kumar Kataria , Mousumi Das

While bars are commonly observed in disk galaxies, the precise conditions governing their formation remain incompletely understood. To investigate these conditions, we perform a suite of N-body simulations of bulgeless disk galaxies with…

Astrophysics of Galaxies · Physics 2025-09-10 Dajeong Jang , Woong-Tae Kim , Yun Hee Lee

We investigated the evolution of interacting disk galaxies using high-resolution $N$-body/SPH simulations, taking into account the multiphase nature of the interstellar medium (ISM). In our high-resolution simulations, a large-scale…

I review some of the work on bars which is closely linked to the bar/bulge system in our Galaxy. Several independent studies, using totally independent methods, come to the same results about the 3D structure of a bar, i.e., that a bar is…

Astrophysics of Galaxies · Physics 2015-06-04 E. Athanassoula

I review the various mechanisms for creating bars in rotating stellar disks, and conclude that the swing-amplified feed-back loop, which produces rapidly tumbling bars, remains the most probable. The bar continues to evolve after its…

Astrophysics · Physics 2007-05-23 J A Sellwood

We show by numerical simulations that a purely stellar dynamical model composed of an exponential disc, a cuspy bulge, and an NFW halo with parameters relevant to the Milky Way Galaxy is subject to bar formation. Taking into account the…

Astrophysics of Galaxies · Physics 2016-08-17 Evgeny Polyachenko , Peter Berczik , Andreas Just

Disc galaxies can be substantially modified by close encounters and mergers, since their discs are very responsive components. Close interactions can be held responsible for the formation of bridges and tails, as well as for the formation…

Astrophysics · Physics 2007-05-23 E. Athanassoula

Galaxy mergers and interactions are mechanisms which could drive the formation of bars. Therefore, we could expect that the fraction of barred galaxies increases with the local density. Here we show the first results of an extensive search…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-24 J. Mendez-Abreu , J. A. L. Aguerri , S. Zarattini , R. Sanchez-Janssen , E. M. Corsini

Stars do not form in isolation but together with other stars, and often in a clustered environment. Depending on the initial conditions in these environments, such as initial density and substructure, the distances of encounters between…

Earth and Planetary Astrophysics · Physics 2024-08-01 Christina Schoettler , James E. Owen

The emergence of a large-scale stellar bar is one of the most striking features in disc galaxies. By means of state-of-the-art cosmological zoom-in simulations, we study the formation and evolution of bars in Milky Way-like galaxies in a…

Astrophysics of Galaxies · Physics 2018-07-23 Tommaso Zana , Massimo Dotti , Pedro R. Capelo , Silvia Bonoli , Francesco Haardt , Lucio Mayer , Daniele Spinoso

We investigate the dynamical effects of an interaction between an initially barred galaxy and a small spherical companion using an N-body/SPH algorithm. In the models described here the small companion passes through the disc of the larger…

Astrophysics · Physics 2009-11-07 I. Berentzen , E. Athanassoula , C. H. Heller , K. J. Fricke

A significant fraction of local galaxies exhibit stellar bars, non-axisymmetric structures composed of stars, gas, and dust. Identifying key differences between the properties of barred and unbarred galaxies can uncover clues about the…

Astrophysics of Galaxies · Physics 2025-05-23 Paula D. López , Cecilia Scannapieco , Sofía A. Cora , Ignacio D. Gargiulo

Using an N-body+SPH code we have performed numerical simulations to investigate the dynamical effects of an interaction between an initially barred galaxy and a small spherical companion. In the models described here the small companion…

Astrophysics · Physics 2009-10-31 I. Berentzen , C. H. Heller , E. Athanassoula , K. J. Fricke

We investigate the evolution of two bars formed in fully self-consistent hydrodynamic simulations of the formation of Milky Way-mass galaxies. One galaxy shows higher central mass concentration and has a longer and stronger bar than the…

Astrophysics of Galaxies · Physics 2015-04-29 Takashi Okamoto , Mari Isoe , Asao Habe