相关论文: Long-lived double-barred galaxies in N-body simula…
We use high resolution collisionless $N$-body simulations to study the secular evolution of disk galaxies and in particular the final properties of disks that suffer a bar and perhaps a bar-buckling instability. Although we find that bars…
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…
Barred galaxies often develop a box/peanut pseudobulge, but they can also host a nearly spherical classical bulge, which is known to gain rotation due to the bar. We aim to explore how the presence of gas impacts the rotation of classical…
We report idealized simulations that mimic the growth of galaxy disks embedded in responsive halos and bulges. The disks manifested an almost overwhelming tendency to form strong bars that we found very difficult to prevent. We found that…
I present a brief review of what is known about double-barred galaxies, where a small ("inner") bar is nested inside a larger ("outer") bar; the review is focused primarily on their demographics and photometric properties. Roughly 20% of…
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…
We performed a series of 29 gasdynamical simulations of disc galaxies, barred and unbarred, with various stellar masses, to study the impact of the bar on star formation history. Unbarred galaxies evolve very smoothly, with a star formation…
Most giant spiral galaxies have pseudo or disk-like bulges that are considered to be the result of purely secular processes. This may challenge the hierarchical scenario predicting about one major merger per massive galaxy ($>$$3\times…
Stellar bars are a common morphological feature of spiral galaxies. While it is known that they can form in isolation, or be induced tidally, few studies have explored the production of stellar bars in galaxy merging. We look to investigate…
Double-barred galaxies are common in the local Universe, with approximately one third of barred spirals hosting an smaller, inner bar. Nested bars have been proposed as a mechanism for transporting gas to the very central regions of the…
Numerical simulations of double-barred galaxies predict the build-up of different structural components (e.g., bulges, inner discs) in the central regions of disc galaxies. In those simulations, inner bars have a prominent role in the…
Disc galaxies can be substantially modified by close encounters and mergers, since their discs are very responsive components. Close interactions can be held responsible for the formation of bridges and tails, as well as for the formation…
We present results of a high-resolution imaging survey of barred S0--Sa galaxies which demonstrate that the central regions of these galaxies are surprisingly complex. We see many inner bars --- small, secondary bars (typically less than a…
I review some of the work on bars which is closely linked to the bar/bulge system in our Galaxy. Several independent studies, using totally independent methods, come to the same results about the 3D structure of a bar, i.e., that a bar is…
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…
In this and in a previous paper (Romero-Gomez et al. 2006) we propose a theory to explain the formation of both spirals and rings in barred galaxies using a common dynamical framework. It is based on the orbital motion driven by the…
Bars in galaxies may form not only through instability, but also as a result of an interaction with another galaxy. In particular, they may appear in disky dwarf galaxies interacting with Milky Way-like galaxies. Here we report the results…
The morphology of the outer rings of early-type spiral galaxies is compared to integrations of massless collisionless particles initially in nearly circular orbits. Particles are perturbed by a quadrupolar gravitational potential…
Under certain conditions, sub-kpc nuclear bars form inside large-scale stellar bars of disk galaxies. These secondary bars spend a fraction of their lifetime in a dynamically-decoupled state, tumbling in the gravitational field of the outer…
Galactic bars drive the internal evolution of spiral galaxies, while their formation is tightly coupled to the properties of their host galaxy and dark matter halo. To explore what drives bar formation in the cosmological context and how…