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Related papers: Most Real Bars are Not Made by the Bar Instability

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The well-known bar instability of rotationally-supported disk galaxy models has been studied extensively since its first discovery over half a century ago. We were therefore very surprised to find cases of disks embedded in rigid halos,…

Astrophysics of Galaxies · Physics 2025-10-24 J. A. Sellwood , Victor P. Debattista , R. G. Carlberg

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 examine the properties of barred disc galaxies in a LCDM cosmological hydrodynamical simulation from the EAGLE project. Our study follows the formation of 269 discs identified at z = 0 in the stellar mass range 10.6 < log Mstr /M < 11.…

Bars in galaxies are mainly supported by particles trapped around closed periodic orbits. These orbits respond to the bar's forcing frequency only and lack free oscillations. We show that a similar situation takes place in double bars:…

Astrophysics · Physics 2015-06-24 Witold Maciejewski

We analyse the properties of strongly barred disc galaxies using the TNG100 simulation, a cosmological hydrodynamical realisation of the IllustrisTNG suite. We identify 270 disc galaxies at $z=0$ in the stellar mass range…

Recent discoveries made with JWST observations include a significant number of barred galaxies at high redshift. Their origin remains unclear and their presence seems difficult to reproduce in cosmological simulations of galaxy formation…

Astrophysics of Galaxies · Physics 2025-09-29 Ewa L. Lokas

I follow a bar from its formation, via its evolution, to its destruction and, perhaps, regeneration. I discuss the main features at each stage and particularly the role of the halo. Bars can form even in sub-maximum discs. In fact, such…

Astrophysics · Physics 2007-05-23 E. Athanassoula

Recent studies have revealed that bars can form as early as a few billion years after the Big Bang, already displaying similar characteristics of evolved bars in the Local Universe. Bars redistribute angular momentum across the galaxy,…

We present simulations of bar-unstable stellar discs in which the bars thicken into box/peanut shapes. Detailed analysis of the evolution of each model revealed three different mechanisms for thickening the bars. The first mechanism is the…

Astrophysics of Galaxies · Physics 2020-05-27 J. A. Sellwood , Ortwin Gerhard

Barred structures are widespread in a considerable fraction of galactic discs, spanning diverse environments and galaxy luminosities. The environment likely exerts a significant influence on bar formation. It is plausible that the…

Astrophysics of Galaxies · Physics 2023-09-22 J. Alfonso L. Aguerri , Virginia Cuomo , Azahara Rojas-Roncero , Lorenzo Morelli

We use high resolution collisionless $N$-body simulations to study the secular evolution of disk galaxies and in particular the final properties of disks that suffer a bar and perhaps a bar-buckling instability. Although we find that bars…

Astrophysics · Physics 2009-11-10 Victor P. Debattista , C. Marcella Carollo , Lucio Mayer , Ben Moore

Stellar bars are important internal drivers of secular evolution in disk galaxies. Using a sample of nearby spiral galaxies with weak and strong bars, we explore the relationships between the star formation feature and stellar bars in…

Astrophysics of Galaxies · Physics 2015-06-22 Zhi-Min Zhou , Chen Cao , Hong Wu

We have measured the bar lengths and widths of 125 barred galaxies observed with CCDs. The dependence of bar strength (identified with bar axis ratio) on morphological type, nuclear activity, central and mid-bar surface brightness is…

Astrophysics · Physics 2007-05-23 S. Chapelon , T. Contini , E. Davoust

Stellar bars are elongated structures in disk galaxies that can torque and funnel gas inward, influencing galaxy evolution. While strong bars are known to induce rapid inflow, the impact of weaker bars remains less certain. We collected…

The central kpc of barred galaxies exhibits a wealth of morphological information on different components with clear dynamical consequences. These include nuclear rings, spirals, bars, and more. We argue that this morphology is driven by…

Astrophysics · Physics 2007-05-23 Isaac Shlosman

We present evidence of bar-induced secular evolution in galactic discs using 3.6 ${\mu m}$ images of nearby galaxies from the Spitzer Survey of Stellar Structure in Galaxies (S4G). We find that among massive galaxies ($M_{star}/M_{sun}>…

Astrophysics of Galaxies · Physics 2016-09-07 Taehyun Kim , Dimitri A. Gadotti , E. Athanassoula , Albert Bosma , Kartik Sheth , Myung Gyoon Lee

There is no doubt that the Milky Way is a barred galaxy; however, factors that establish its prominent morphology remain largely elusive and poorly comprehended. In this work, we attempt to constrain the history of the MW by tracing the…

Astrophysics of Galaxies · Physics 2024-07-16 Sergey Khoperskov , Ivan Minchev , Matthias Steinmetz , Bridget Ratcliffe , Jakob C. Walcher , Noam Libeskind

By using $N$-body and hydro simulations, we study the formation and evolution of bars in galaxies with significant gas content focusing on the phenomenon of the buckling instability. The galaxies are initially composed of a spherical dark…

Astrophysics of Galaxies · Physics 2020-02-26 Ewa L. Lokas

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

We present the first attempt to analyse the growth of the bar instability in stellar-gaseous disks evolving in a fully consistent cosmological scenario. We explored the role of the cosmology on pure stellar disks with different mass…

Astrophysics · Physics 2008-09-24 Anna Curir , Paola Mazzei , Giuseppe Murante