Related papers: Induced Nested Galactic Bars Inside Assembling Dar…
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…
The dynamic evolution of galactic bars in standard $\Lambda$CDM models is dominated by angular momentum loss to the dark matter haloes via dynamical friction. Traditional approximations to dynamical friction are formulated using the…
Aims: We want to investigate the growth of bar instability in stellar disks embedded in a suitable dark matter halo evolving in a fully consistent cosmological framework. Methods: We perform seven cosmological simulations to emphasise the…
We propose that massive central objects form in the centers of the bars which must develop in young high-surface density galactic disks. Large-scale dynamics shuts off the growth of the central mass before it reaches $\sim 2%$ of the disk…
We study dynamics of bars in models of disk galaxies embeded in realistic dark matter halos. We find that disk thickness plays an important, if not dominant, role in the evolution and structure of the bars. We also make extensive numerical…
We investigate the gravitational interactions between live stellar disks and their dark matter halos, using LCDM haloes similar in mass to that of the Milky Way taken from the Aquarius Project. We introduce the stellar disks by first…
The role of gas in the mass assembly at the nuclei of galaxies is still subject to some uncertainty. Stellar nuclear discs bridge the gap between the large-scale galaxy and the central massive objects that reside there. Using a high…
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…
Orbits are the key building blocks of any density distribution and their study helps us understand the kinematical structure and the evolution of galaxies. Here we investigate orbits in a tidally induced bar of a dwarf galaxy, using an…
Strong galactic bars produced in simulations tend to undergo a period of buckling instability that weakens and thickens them and forms a boxy/peanut structure in their central parts. This theoretical prediction has been confirmed by…
We discuss the mechanism(s) of bar formation in isolated and tidally interacting disk galaxies using the results of idealized collisionless Nbody simulations of the galaxies. In order to better understand the mechanism, we investigate…
I show that strong bars can grow in galactic discs, even when the latter are immersed in haloes whose mass within the disc radius is comparable to, or larger than, the mass of the disc. I argue that this is due to the response of the halo…
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…
We examine solutions of the hydrodynamic equations for dark matter (DM) modeled as a Bose-Einstein condensate (BEC) with axionlike interaction, forming a spherically symmetric halo in dwarf galaxies. Small perturbations and decoherence of…
Recent progress in the understanding of the role of bars and gravitational instabilities in galaxy disks is reviewed. It has been proposed that bars can produce mass transfer towards the center, and progressively metamorphose late-type…
It is well established that bars evolve significantly after they form in galaxy discs, often changing shape both in and out of the disc plane. In some cases they may bend or buckle out of the disc plane resulting in the formation of…
We study the formation of stellar bars using 145 simulations of disc galaxies embedded in live and static dark matter haloes. We use the exponential bar growth timescale, $\tau_{\rm bar}$, to quantify how disc structure and kinematics…
Bars are among the most prominent structures in disk galaxies. While the widely accepted swing-amplification theory provides a qualitative framework for their formation, the detailed physical processes remain incompletely understood.…
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}>…
I discuss results from the COSMOS survey, showing that the fraction of disc galaxies that is barred decreases considerably with look-back time from z ~ 0.2 to z ~ 0.8. This decrease is more important for small mass and low luminosity…