Related papers: Orbital Structure Evolution in Self-Consistent N-b…
In this paper I argue that, far from necessarily hindering bar formation in disc galaxies, inner haloes may stimulate it. This constitutes a new instability mechanism by which bars can grow. To show this I use a number of N-body simulations…
The vertical profiles of disc galaxies are built by the material trapped around stable periodic orbits, which form their "skeletons". According to this, the knowledge of the stability of the main families of periodic orbits in appropriate…
We run self-consistent simulations of Milky Way-sized, isolated disk galaxies to study formation and evolution of a stellar bar as well as a nuclear ring in the presence of gas. We consider two sets of models with cold or warm disks that…
Boxy/peanut (b/p) bulges, the vertically extended inner parts of bars, are ubiquitous in barred galaxies in the local Universe, including our own Milky Way. At the same time, a majority of external galaxies and the Milky Way also possess a…
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…
The class `bulges' contains objects with very different formation and evolution paths and very different properties. I review two types of `bulges', the boxy/peanut bulges (B/Ps) and the discy bulges. The former are parts of bars seen…
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…
We investigate whether the formation mechanism of boxy and peanut-shaped (B/PS) bulges could depend on the gas content of the galaxy. We have performed N-body simulations with and without a gaseous component. In the second case star…
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…
We study the dynamical mechanisms that reinforce the formation of boxy structures in the \textit{inner} regions, roughly in the middle, of bars observed nearly \textit{face-on}. Outer boxiness, at the ends of the bars, is usually associated…
A live halo plays an active role in the formation and evolution of bars by participating in the angular momentum redistribution which drives the dynamical evolution. Angular momentum is emitted mainly by near-resonant material in the bar…
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…
From this vast subject, I will pick out and review three specific topics, namely the formation and evolution of bars, the formation of bulges, and the evolution during multiple major mergers. Bars form naturally in galactic discs. Their…
We discuss the evolution of a disc galaxy due to the formation of a bar and, subsequently, a peanut. After the formation stage there is still considerable evolution, albeit slower. In purely stellar cases the pattern speed of the bar…
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…
Using N-body simulations, we study the properties of a bar induced in a dwarf galaxy as a result of tidal interaction with the Milky Way. The dwarf is initially composed of a disk embedded in a dark matter halo and we follow its evolution…
We discuss the morphology, photometry and kinematics of the bars which have formed in three N-body simulations. These have initially the same disc and the same halo-to-disc mass ratio, but their haloes have very different central…
We have observed 60 edge-on galaxies in the NIR in order to study the stellar distribution in galaxies with box/peanut-shaped bulges. The much smaller amount of dust extinction at these wavelengths allows us to identify in almost all target…
Galactic bars and their associated resonances play a significant role in shaping galaxy evolution. Resulting resonance-driven structures, like the vertically extended Boxy/Peanut X-Feature (BPX), then serve as a useful probe of the host…
We track the angular momentum transfer in n-body simulations of barred galaxies by measuring torques to understand the dynamical mechanisms responsible for the evolution of the bar-disc-dark matter halo system. We find evidence for three…