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Related papers: Barless flocculent galaxies: a dynamic puzzle

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Although nearly one-third of barred galaxies host an inner, secondary bar, the formation and evolution of double barred galaxies remain unclear. We show here an example model of a galaxy, dominated by a live dark matter halo, in which…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-15 Kanak Saha , Witold Maciejewski

The characteristics of the galactic bars that are prone to suffer a damaging impact from a massive central black hole are examined using flat stellar disks. We construct three disk model groups that consist of exponential disks with one…

Astrophysics of Galaxies · Physics 2015-05-30 Shunsuke Hozumi

To further enhance our understanding on the formation and evolution of bars in lenticular (S0) galaxies, we are undertaking a detailed photometric and spectroscopic study on a sample of 22 objects. Here we report the results of a 2D…

Astrophysics · Physics 2009-11-07 Dimitri A. Gadotti , Ronaldo E. de Souza

Although more than two-thirds of star-forming disk galaxies in the local universe are barred, some galaxies remain un-barred, occupying the upper half of the Hubble tuning fork diagram. Numerical simulations almost always produce bars…

Astrophysics of Galaxies · Physics 2018-05-16 Kanak Saha , Bruce Elmegreen

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

The central part of a dark matter halo reacts to the presence and evolution of a bar. Not only does the halo absorb angular momentum from the disk, it can also be compressed and have its shape modified. We study these issues in a series of…

Astrophysics · Physics 2009-11-13 P. Colin , O. Valenzuela , A. Klypin

Simulations and observations of galactic bars suggest they do not commonly evolve into bulges, although it is possible that the earliest bars formed bulges long ago, when galaxies were smaller, denser, and had more gas. The most highly…

Astrophysics · Physics 2015-06-24 Bruce G. Elmegreen

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

Galaxy surveys have shown that luminous galaxies are mainly distributed in large filaments and galaxy clusters. The remaining large volumes are virtually devoid of luminous galaxies. This is in concordance with the formation of the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-18 Matthias Hoeft , Stefan Gottloeber

We describe fully self-consistent N-body experiments of barred galaxies with massive halos. A rotating bar is braked through dynamical friction with the halo, which occurs on a short time scale when the central density of the halo is high.…

Astrophysics · Physics 2007-05-23 Victor P. Debattista , J. A. Sellwood

While the total interior mass of a galaxy is reasonably well determined by a good rotation curve, the relative contributions from disk, bulge and halo are only weakly constrained by one-dimensional data. Barred galaxies are intrinsically…

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

The evolution of disk galaxies in modified gravity is studied by using high-resolution N-body simulations. More specifically, we use the weak field limit of two modified gravity theories, i.e., nonlocal gravity (NLG) and…

Astrophysics of Galaxies · Physics 2020-05-28 Neda Ghafourian , Mahmood Roshan , Shahram Abbassi

The presence of unseen halos of ``dark matter'' has long been inferred from the high rotation speeds of gas and stars in the outer parts of spiral galaxies$^{1}$. The volume density of this dark matter decreases less quickly from the…

Astrophysics · Physics 2009-10-22 Penny D. Sackett , Heather L. Morrison , Paul Harding , Todd A. Boroson

We use high-resolution numerical simulations to follow the barred disk evolution in a suite of models with progressively more massive stellar bulges, with bulge-to-total (disk$+$bulge) mass ratios of $B/T\sim 0-0.25$, embedded in dark…

Astrophysics of Galaxies · Physics 2023-10-03 Xingchen Li , Isaac Shlosman , Daniel Pfenniger , Clayton Heller

The observation of a massive galaxy with an extremely low dark matter content (i.e. NGC 1277) has posed questions about how such objects form and evolve in a hierarchical universe. We here report on the finding of several massive, dark…

It has been known for some time that rotating bars in galaxies slow due to dynamical friction against the halo. However, recent attempts to use this process to place constraints on the dark matter density in galaxies and possibly also to…

Astrophysics · Physics 2016-08-30 J. A. Sellwood

The low surface brightness galaxies are gas-rich and yet have a low star formation rate, this is a well-known puzzle. The spiral features in these galaxies are weak and difficult to trace, although this aspect has not been studied much.…

Astrophysics of Galaxies · Physics 2016-01-14 Soumavo Ghosh , Chanda J. Jog

More than 50 per cent of present-day massive disc galaxies show a rotating stellar bar. Their formation and dynamics have been widely studied both numerically and observationally. Although numerical simulations in the $\Lambda$CDM…

Astrophysics of Galaxies · Physics 2022-01-17 Ornela F. Marioni , Mario G. Abadi , Stefan Gottlöber , Gustavo Yepes

We use cosmological hydrodynamical simulations of the APOSTLE project along with high-quality rotation curve observations to examine the fraction of baryons in {\Lambda}CDM haloes that collect into galaxies. This 'galaxy formation…

In this review we outline the major points of ab-initio cosmological models focusing on some galaxy evolution unresolved problems. In particular our knowledge of the star formation rate which leads galaxy evolution, i.e. luminosity, colors…

Astrophysics · Physics 2009-09-29 Paola Mazzei