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Related papers: Bar instability in cosmological halos

200 papers

We perform controlled N-body simulations of disc galaxies growing within live dark matter (DM) haloes to present-day galaxies that contain both thin and thick discs. We consider two types of models: a) thick-disc initial conditions to which…

Astrophysics of Galaxies · Physics 2017-06-14 Michael Aumer , James Binney

We study the detailed structure of galaxies at redshifts z > 2 using cosmological simulations with improved modeling of the interstellar medium and star formation. The simulations follow the formation and dissociation of molecular hydrogen,…

Astrophysics of Galaxies · Physics 2012-09-21 Marcel Zemp , Oleg Y. Gnedin , Nickolay Y. Gnedin , Andrey V. Kravtsov

In this paper, we use the Galaxy Zoo 2 dataset to study the behavior of bars in disk galaxies as a function of specific star formation rate (SSFR), and bulge prominence. Our sample consists of 13,295 disk galaxies, with an overall (strong)…

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

In the $\Lambda$-CDM paradigm, the dark halo governs the gravitational potential within which a galaxy can form and evolve. In this Letter we show that the present-day inner ($r<50\text{ kpc}$) dark halo can be significantly misaligned with…

Astrophysics of Galaxies · Physics 2023-09-18 Jiwon Jesse Han , Vadim Semenov , Charlie Conroy , Lars Hernquist

The physical mechanisms responsible for bar formation and destruction in galaxies remain a subject of debate. While we have gained valuable insight into how bars form and evolve from isolated idealized simulations, in the cosmological…

Cosmological N-body simulations indicate that the dark matter haloes of galaxies should be generally triaxial. Yet, the presence of a baryonic disc is believed to alter the shape of the haloes. Here we aim to study how bar formation is…

Cosmology and Nongalactic Astrophysics · Physics 2013-11-19 Rubens E. G. Machado , E. Athanassoula

We use the Spitzer Survey of Stellar Structure in Galaxies (S$^{4}$G) 3.6 $\mu$m imaging to study the properties (length and strength) and fraction of bars at $z=0$. We use the maximum of tangential-to-radial force ratio in the bar region…

Astrophysics of Galaxies · Physics 2016-07-26 Simón Díaz-García , Heikki Salo , Eija Laurikainen , Martín Herrera-Endoqui

This thesis investigates the dynamical effect of two structural components of disk galaxies, namely, the dark matter halo and the interstellar gas on the origin and persistence issue of spiral structure in disk galaxies through theoretical…

Astrophysics of Galaxies · Physics 2018-07-04 Soumavo Ghosh

Owing to the pioneering work of Contopoulos, a strongly barred galaxy is known to have irregular orbits in the vicinity of the bar. By definition, irregular orbits can not be represented by action-angle tori everywhere in phase space. This…

Astrophysics of Galaxies · Physics 2015-08-26 Martin D. Weinberg

Within the standard hierarchical structure formation scenario, Milky Way-mass dark matter haloes have hundreds of dark matter subhaloes with mass $\gtrsim 10^8 \, {\rm M_{\odot}}$. Over the lifetime of a galactic disc a fraction of these…

Astrophysics of Galaxies · Physics 2018-06-12 Shaoran Hu , Debora Sijacki

Numerical-relativity simulation is performed for rapidly spinning black holes (BHs) in a higher-dimensional spacetime of special symmetries for the dimensionality $6 \leq d \leq 8$. We find that higher-dimensional BHs, spinning rapidly…

General Relativity and Quantum Cosmology · Physics 2014-11-20 Masaru Shibata , Hirotaka Yoshino

Previous simulations of self-gravitating protostellar disks have shown that, once developed, gravitational instabilities are enhanced by cooling the disk constantly during its evolution (Pickett et al. 2002). These earlier calculations…

Astrophysics · Physics 2007-05-23 Annie C. Mejía , Richard H. Durisen , Megan K. Pickett

The non-linear dynamics of bending instability and vertical structure of a galactic stellar disc embedded into a spherical halo are studied with N-body numerical modelling. Development of the bending instability in stellar galactic disc is…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-19 A. Khoperskov , D. Bizyaev , N. Tiurina , M. Butenko

Using analytic stability criteria, 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 nonaxisymmetric modes such as bars. However, depending on…

Astrophysics · Physics 2007-05-23 Chris Mihos , Stacy McGaugh , Erwin de Blok

We characterize empirically the radial diffusion of stars in the plane of a typical barred disk galaxy by calculating the local spatial diffusion coefficient and diffusion time-scale for bulge-disk-halo N-body self-consistent systems which…

Astrophysics of Galaxies · Physics 2015-05-30 Maura Brunetti , Cristina Chiappini , Daniel Pfenniger

We analyse the evolution of turbulence and gravitational instability of a galactic disc in a quasi-steady state governed by cosmological inflow. We focus on the possibility that the coupling between the in-streaming gas and the disc is…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Shy Genel , Avishai Dekel , Marcello Cacciato

Bars are important in the secular evolution of galaxies. This study is aimed at exploring the reasons why some galaxies have bars at redshift $z=0$ while others do not. We use ellipse fitting to measure the properties and evolution of bars…

Astrophysics of Galaxies · Physics 2025-05-28 Shuai Lu , Min Du , P. Victor Debattista

This paper describes test particle simulations of the response of the outer parts of Galactic disks to barring and spiral structure. Simulations are conducted for cold Mestel disks and warm quasi-exponential disks with completely flat…

Astrophysics · Physics 2009-11-10 Dalia Chakrabarty

Using observational data on the kinematical properties and density distributions of the subsystems of the Milky Way galaxy, we construct a set of multi-component equilibrium models of its disk. The dynamics of the disk is studied…

Astrophysics of Galaxies · Physics 2019-12-17 V. I. Korchagin , S. S. Khrapov , A. V. Khoperskov