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Related papers: Stellar Bar Evolution in Cuspy and Flat-Cored Tria…

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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

N-body simulations and analytical calculations of the gravitational collapse in an expanding universe predict that halos should form with a diverging inner density profile, the cusp. There are some observational indications that the dark…

Astrophysics · Physics 2009-11-06 Amr El-Zant , Isaac Shlosman , Yehuda Hoffman

We analyse the output of the hi-res cosmological zoom-in simulation ErisBH to study self-consistently the formation of a strong stellar bar in a Milky Way-type galaxy and its effect on the galactic structure, on the central gas distribution…

Astrophysics of Galaxies · Physics 2016-12-28 Daniele Spinoso , Silvia Bonoli , Massimo Dotti , Lucio Mayer , Piero Madau , Jillian Bellovary

A strong bar rotating within a massive halo should lose angular momentum to the halo through dynamical friction, as predicted by Weinberg. We have conducted fully self-consistent, numerical simulations of barred galaxy models with a live…

Astrophysics · Physics 2015-06-24 J. A. Sellwood , Victor P. Debattista

Galactic disks can form in asymmetric potentials of the assembling dark matter (DM) halos, giving rise to the first generation of gas-rich bars. Properties of these bars differ from canonical bars analyzed so far. Moreover, rapid disk…

Astrophysics · Physics 2008-12-05 Isaac Shlosman

This paper explores resonance-driven secular evolution between a bar and dark-matter halo using N-body simulations. We make direct comparisons to our analytic theory (Weinberg & Katz 2005) to demonstrate the great difficulty that an N-body…

Astrophysics · Physics 2008-11-26 Martin D. Weinberg , Neal Katz

Recent developments in computer hardware and software enable researchers to simulate the self-gravitating evolution of galaxies at a resolution comparable to the actual number of stars. Here we present the results of a series of such…

Astrophysics of Galaxies · Physics 2018-04-04 Michiko S. Fujii , Jeroen Bédorf , Junichi Baba , Simon Portegies Zwart

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 measure the redshift evolution of the bar fraction in a sample of 2380 visually selected disc galaxies found in Cosmic Evolution Survey (COSMOS) Hubble Space Telescope (HST) images. The visual classifications used to identify both the…

We study the behaviors of galactic disks in triaxial halos both numerically and analytically to see if warps can be excited and sustained in triaxial potentials. We consider the following two scenarios: 1) galactic disks that are initially…

Astrophysics of Galaxies · Physics 2011-02-11 Myoungwon Jeon , Sungsoo S. Kim , Hong Bae Ann

Bars and spiral arms have played an important role as constraints on the dynamics and on the distribution of dark matter in the optical parts of disk galaxies. Dynamics linked to the dissipative nature of gas, and its transformation into…

Astrophysics · Physics 2016-01-27 Daniel Pfenniger , Yves Revaz

We employ high-resolution zoom-in cosmological simulations to analyze the emerging morphology of galaxies in dark matter halos at redshifts z > 2. We choose DM halos of similar masses of log (Mvir/Mo) ~11.65 +- 0.05 at the target redshifts…

Astrophysics of Galaxies · Physics 2022-02-23 Da Bi , Isaac Shlosman , Emilio Romano-Diaz

The dark matter halos in $\Lambda$CDM cosmological simulations are triaxial and highly flattened. In many cases, these triaxial equilibria are also tumbling slowly, typically about their short axes, with periods of order a Hubble time.…

Astrophysics of Galaxies · Physics 2015-05-13 John Dubinski , Dalia Chakrabarty

Several mechanisms of bar formation in stellar galactic disks are considered, including Toomre swing amplification and normal mode approach. On example of the well-known model of Kuzmin--Toomre using N-body simulations it was shown that the…

Astrophysics of Galaxies · Physics 2015-06-11 Evgeny Polyachenko

It is well-established that strong bars rotating in dense halos generally slow down as they lose angular momentum to the halo through dynamical friction. Angular momentum exchanges between the bar and halo particles take place at…

Astrophysics · Physics 2009-11-13 J. A. Sellwood , Victor P. Debattista

Motivated by the observation of extended stellar cores in dark matter (DM) dominated dwarf galaxies, this study investigates a simple mechanism by which stellar cores can form as a result of DM halo expansion. Several non-CDM models predict…

Astrophysics of Galaxies · Physics 2025-10-22 Jorge Sanchez Almeida , Angel R. Plastino , Ignacio Trujillo

A clear prediction of the Cold Dark Matter model is the existence of cuspy dark matter halo density profiles on all mass scales. This is not in agreement with the observed rotation curves of spiral galaxies, challenging on small scales the…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Andrea V. Maccio' , Greg Stinson , Chris B. Brook , James Wadsley , H. M. P. Couchman , Sijing Shen , Brad K. Gibson , Tom Quinn

Many of the Milky Way's accreted substructures have been discovered and studied in the space of energy $E$, and angular momentum components $L_z$ and $L_{\bot}$. In a static axisymmetric system, these quantities are (reasonable…

Astrophysics of Galaxies · Physics 2025-08-27 Hanneke C. Woudenberg , Amina Helmi

We confirm that a high rate of shear at the center is able to stabilize an entire stellar disk against bar-forming (m=2) modes, irrespective of the dark halo density. Our simulations of unstable power-law disks also yield the growth rate…

Astrophysics · Physics 2009-10-31 J A Sellwood , N W Evans

We study the dynamics of galactic disk formation and evolution in 'realistic' LambdaCDM haloes with idealized baryonic initial conditions. We add rotating spheres of hot gas at z=1.3 to two fully cosmological dark-matter-only halo…

Astrophysics of Galaxies · Physics 2015-06-04 Michael Aumer , Simon D. M. White