Related papers: Assessing Disk Galaxy Stability through Time
The influence of central black holes on the dynamical evolution of bars in disk galaxies is examined. In particular, we use numerical simulation to estimate the minimum mass black hole (BH) needed to destroy a bar. Initially, bars form in…
Bars in spiral galaxies can weaken through gas inflow towards the center, and angular momentum transfer. Several bar episodes can follow one another in the life of the galaxy, if sufficient gas is accreted from the intergalactic medium to…
The Milky Way as well as a majority of external galaxies possess a thick disc. However, the dynamical role of the (geometrically) thick disc on the bar formation and evolution is not fully understood. Here, we investigate the effect of…
The formation of bars in disk galaxies is a tracer of the dynamical maturity of the population. Previous studies have found that the incidence of bars in disks decreases from the local Universe to z ~ 1, and by z > 1 simulations predict…
Most galaxies have a warped shape when they are seen from an edge-on point of view. The reason for this curious form is not completely known so far and in this work we apply dynamical system tools to contribute to its explanation. Starting…
More than two thirds of disk galaxies are barred to some degree. Many today harbor massive concentrations of gas in their centers, and some are known to possess supermassive black holes (SMBHs) and their associated stellar cusps. Previous…
Double-barred galaxies account for almost one third of all barred galaxies, suggesting that secondary stellar bars, which are embedded in large-scale primary bars, are long-lived structures. However, up to now it has been hard to…
We have measured the radial light profiles and global shapes of bars using two-dimensional 3.6 $\mu m $ image decompositions for 144 face-on barred galaxies from the Spitzer Survey of Stellar Structure in Galaxies (S4G). The bar surface…
While bars are common in disk galaxies, their formation conditions are not well understood. We use $N$-body simulations to study bar formation and evolution in isolated galaxies consisting of a stellar disk, a classical bulge, and a dark…
The joint influence of numerical parameters such as the number of particles N, the gravitational softening length $\epsilon$ and the time-step $\Delta t$ is investigated in the context of galaxy simulations. For isolated galaxy models we…
Although at least one quarter of early-type barred galaxies host secondary stellar bars embedded in their large-scale primary counterparts, the dynamics of such double barred galaxies are still not well understood. Recently we reported…
Recent studies have revealed that bars can form as early as a few billion years after the Big Bang, already displaying similar characteristics of evolved bars in the Local Universe. Bars redistribute angular momentum across the galaxy,…
The origin of spiral patterns in galaxies is still not fully understood. Similar features also develop readily in N-body simulations of isolated cool, collisionless disks, yet even here the mechanism has yet to be explained. In this series…
Dynamical evolution of spiral galaxies is strongly dependent on non-axisymmetric patterns that develop from gravitational instabilities, either spontaneously or externally triggered. Some evolutionary sequences are described through which a…
This paper describes a framework for studying galaxy morphology, particularly bar strength, in a quantitative manner, and presents applications of this approach that reveal observational evidence for secular evolution in bar morphology. The…
Although stellar bars are prevalent in local galaxies, unbarred galaxies constitute a significant fraction, particularly at high redshifts. While some galaxies are unbarred by nature due to stability against the bar instability, several…
Some 30% of disc galaxies have a pronounced central bar feature in the disc plane and many more have weaker features of a similar kind. Kinematic data indicate that the bar constitutes a major non-axisymmetric component of the mass…
We present three-dimensional simulations of the dynamical bar-mode instability in magnetized and differentially rotating stars in full general relativity. Our focus is on the effects that magnetic fields have on the dynamics and the onset…
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…
By using $N$-body and hydro simulations, we study the formation and evolution of bars in galaxies with significant gas content focusing on the phenomenon of the buckling instability. The galaxies are initially composed of a spherical dark…