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Related papers: Bar Dissolution in Prolate Halos

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It has been proposed that close interactions with satellite galaxies can significantly perturb the morphology of the main galaxy. However, the dynamics of an already formed bar following the interaction with the external environment has not…

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

Galactic bars, made up of elongated and aligned stellar orbits, can lose angular momentum via resonant torques with dark matter particles in the halo and slow down. Here we show that if a stellar bar is decelerated to zero rotation speed,…

Astrophysics of Galaxies · Physics 2023-05-12 Angela Collier , Ann-Marie Madigan

Galactic bars are found in the majority of disc galaxies. They rotate nearly rigidly with an angular frequency called pattern speed. Previous idealised simulations have shown that bar pattern speed decreases with time due to dynamical…

Astrophysics of Galaxies · Physics 2024-12-11 Marcin Semczuk , Walter Dehnen , Ralph Schönrich , E. Athanassoula

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

Elongated, bar-like galaxies without a significant disk component, with little rotation support and no gas, often form as a result of tidal interactions with a galaxy cluster, as was recently demonstrated using the IllustrisTNG-100…

Astrophysics of Galaxies · Physics 2020-10-14 Ewa L. Lokas

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 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

Using N-body simulations, we examine the impact of dark matter (DM) halo resolution and gravitational softening on bar formation. We generate isolated disk-halo systems with fixed stellar disk parameters, varying the number of halo…

Astrophysics of Galaxies · Physics 2026-03-04 S. Kwak , I. Minchev , M. Steinmetz , S. K. Yi

In this paper, we systematically explore the impact of a galactic bar on the inspiral time-scale of a massive object (MO) within a Milky Way-like galaxy. We integrate the orbit of MOs in a multi-component galaxy model via a semi-analytical…

Astrophysics of Galaxies · Physics 2022-03-14 Elisa Bortolas , Matteo Bonetti , Massimo Dotti , Alessandro Lupi , Pedro R. Capelo , Lucio Mayer , Alberto Sesana

We have performed for the first time in the literature a 2D structural analysis on the barred lenticular and face--on galaxies NGC 4608 and NGC 5701. The results indicate that these galaxies either have never had large disks or their disks…

Astrophysics · Physics 2009-11-07 D. A. Gadotti , R. E. de Souza

We have performed a high mass and force resolution simulation of an idealized galaxy forming from dissipational collapse of gas embedded in a spherical dark matter halo. The simulation includes star formation and effects of stellar…

We study the evolution of simulated disk galaxies in the context of a nonlocal theory of gravity. In this theory the appearance of the dark matter problem in cosmology and astrophysics is a manifestation of the nonlocality of the…

General Relativity and Quantum Cosmology · Physics 2019-02-08 Mahmood Roshan , Sohrab Rahvar

Bars in galaxies may develop through a global instability or due to an interaction with another system. We study bar formation in disky dwarf galaxies orbiting a Milky Way-like galaxy. We employ $N$-body simulations to study the impact of…

Astrophysics of Galaxies · Physics 2017-06-28 Grzegorz Gajda , Ewa L. Lokas , E. Athanassoula

Recent observational constraints restrict the strict applicability of stellar dynamics in spirals to a few rotation periods. However, stellar dynamics concepts such as periodic orbits are invaluable for understanding the various dynamical…

Astrophysics · Physics 2008-02-03 D. Pfenniger

We study dynamics of bars in models of disk galaxies embeded in realistic dark matter halos. We find that disk thickness plays an important, if not dominant, role in the evolution and structure of the bars. We also make extensive numerical…

Astrophysics · Physics 2015-05-13 A. Klypin , O. Valenzuela , P. Colin , T. Quinn

Bars in spiral galaxies can weaken through gas inflow towards the center, and angular momentum transfer. Several bar episodes can follow one another in the life of the galaxy, if sufficient gas is accreted from the intergalactic medium to…

Astrophysics · Physics 2008-11-05 F. Combes

We discuss the evolution of a disc galaxy due to the formation of a bar and, subsequently, a peanut. After the formation stage there is still considerable evolution, albeit slower. In purely stellar cases the pattern speed of the bar…

Astrophysics · Physics 2009-11-07 E. Athanassoula

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

Galactic archaeologists often assume that integrals of motion (IoMs) such as $L_z$ and $E$ are conserved, so substructure remains frozen in IoM space over many Gyr. However, this is not true in the Milky Way due in part to its rotating bar.…

Astrophysics of Galaxies · Physics 2025-09-03 Adam M. Dillamore , Jason L. Sanders

Strong galactic bars produced in simulations tend to undergo a period of buckling instability that weakens and thickens them and forms a boxy/peanut structure in their central parts. This theoretical prediction has been confirmed by…

Astrophysics of Galaxies · Physics 2019-04-03 Ewa L. Lokas