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Related papers: Bars in Cuspy Dark Halos

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We demonstrate that growth of stellar bars in spinning dark matter halos is heavily suppressed in the secular phase of evolution, using numerical simulations of isolated galaxies. In a representative set of models, we show that for values…

Astrophysics of Galaxies · Physics 2015-06-18 Stacy Long , Isaac Shlosman , Clayton Heller

Adaptive SPH and N-body simulations were carried out to study the evolution of the equilibrium structure of dark matter halos that result from the gravitational instability and fragmentation of cosmological pancakes. Such halos resemble…

Astrophysics · Physics 2009-11-06 Marcelo Alvarez , Paul R. Shapiro , Hugo Martel

The secular evolution of disk galaxies is largely driven by resonances between the orbits of 'particles' (stars or dark matter) and the rotation of non-axisymmetric features (spiral arms or a bar). Such resonances may also explain kinematic…

Astrophysics of Galaxies · Physics 2023-05-19 Chris Hamilton , Elizabeth A. Tolman , Lev Arzamasskiy , Vinícius N. Duarte

Many barred galaxies, possibly including the Milky Way, have cusps in the centres. There is a widespread belief, however, that usual bar instability taking place in bulgeless galaxy models is impossible for the cuspy models, because of the…

Astrophysics of Galaxies · Physics 2017-02-07 E. V. Polyachenko , P. Berczik , A. Just

Stellar bars in disk galaxies grow as stars in near circular orbits lose angular momentum to their environments, including their Dark Matter (DM) halo, and transform into elongated bar orbits. This angular momentum exchange during galaxy…

Astrophysics of Galaxies · Physics 2024-10-04 Sioree Ansar , Mousumi Das

We show that the exponential growth rate of a bar in a stellar disk is substantially greater when the disk is embedded in a live halo than in a rigid one having the same mass distribution. We also find that the vigor of the instability in…

Astrophysics of Galaxies · Physics 2016-03-16 J. A. Sellwood

The spin of dark halos has been shown to significantly affect bar formation and evolution in disk galaxies. To understand the physical role of the halo spin on bar formation, we run $N$-body simulations of isolated, Milky Way-sized galaxies…

Astrophysics of Galaxies · Physics 2024-06-14 Dajeong Jang , Woong-Tae Kim

We investigate the structure of the dark matter halo formed in the cold dark matter scenario using $N$-body simulations. We simulated 12 halos with the mass of $6.6\times 10^{11}M_{\odot}$ to $8.0\times 10^{14}M_{\odot}$. In almost all…

Astrophysics · Physics 2008-11-26 Toshiyuki Fukushige , Junichiro Makino

We study the stellar bar growth in high resolution numerical galaxy models with and without dark matter halos. In all models the galactic disk is exponential and the halos are rigid or live Plummer spheres. More specifically, when there is…

Astrophysics of Galaxies · Physics 2018-02-21 Mahmood Roshan

We investigate the formation and evolution of nested bar systems in disk galaxies in a cosmological setting by following the development of an isolated dark matter (DM) and baryon density perturbation. The disks form within the assembling…

Astrophysics · Physics 2009-11-11 Clayton Heller , Isaac Shlosman , Lia Athanassoula

In this paper we examine the effect of the formation and evolution of the disk galaxy on the distribution of dark halo matter. We have made simulations of isolated dark matter (DM) halo and two component (DM + baryons). N-body technique was…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 S. A. Khoperskov , B. M. Shustov , A. V. Khoperskov

We discuss various aspects of the inner structure formation in virialized dark matter (DM) halos that form as primordial density inhomogeneities evolve in the cosmological standard model. The main focus is on the study of central…

Cosmology and Nongalactic Astrophysics · Physics 2012-09-04 A. G. Doroshkevich , V. N. Lukash , E. V. Mikheeva

The condensation of baryons within a dark matter (DM) halo during galaxy formation should result in some contraction of the halo as the combined system settles into equilibrium. We quantify this effect on the cuspy primordial halos…

Astrophysics of Galaxies · Physics 2022-09-21 Pengfei Li , Stacy S. McGaugh , Federico Lelli , James M. Schombert , Marcel S. Pawlowski

We investigate the dynamical response of dispersion-dominated halo populations to a rotating galactic bar, focusing on how the underlying halo phase space distribution function (DF), and in particular the orbital anisotropy, shapes resonant…

Astrophysics of Galaxies · Physics 2026-05-29 Paula Gherghinescu , Francesca Fragkoudi , Alis Deason

Cosmological simulations show that dark matter halos surrounding baryonic disks have a wide range of angular momenta, measured by the spin parameter ($\lambda$). In this study, we bring out the importance of inner angular momentum($<$30…

Astrophysics of Galaxies · Physics 2022-12-14 Sandeep Kumar Kataria , Juntai Shen

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

We use $N$-body simulations to investigate the distinct bar formation processes in disks residing in halos of various concentrations. In a highly concentrated halo, the bar development is limited by the dominant multi-arm modes as a result…

Astrophysics of Galaxies · Physics 2026-01-27 T. Worrakitpoonpon

The halo plays a crucial role in the evolution of barred galaxies. Its near-resonant material absorbs angular momentum emitted from some of the disc particles and helps the bar become stronger. As a result, a bar (oval) forms in the inner…

Astrophysics · Physics 2015-06-24 E. Athanassoula

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

Evolution of stellar bars in disk galaxies is accompanied by dynamical instabilities and secular changes. Following the vertical buckling instability, the bars are known to weaken dramatically and develop a pronounced boxy/peanut shape when…

Astrophysics · Physics 2009-11-13 Inma Martinez-Valpuesta , Isaac Shlosman , Clayton Heller