Related papers: New Results on Bar-Halo Interactions
In this review, I discuss just three aspects of the stability and evolution of galactic discs. (1) I first review our understanding of the bar instability and how it can be controlled. Disc galaxies in which the orbital speed does not…
Self-consistent bars that form in galaxies embedded within cuspy halos are unable to flatten the cusp. Short bars form in models with quasi-flat rotation curves. They lose angular momentum to the halo through dynamical friction, but the…
We study the persistence of warps in galactic discs in the presence of massive halos. A disc is approximated by a set of massive rings, while a halo is represented by a conventional n-body simulation. We confirm the conclusion of Nelson &…
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…
Bars are an elongated structure that extends from the centre of galaxies, and about one-third of disk galaxies are known to possess bars. These bars are thought to form either through a physical process inherent in galaxies, or through an…
About one third of early-type barred galaxies host small-scale secondary bars. The formation and evolution of such double-barred galaxies remain far from being well understood. In order to understand the formation of such systems, we…
Any perturbation to a disc galaxy that creates a misalignment between the planes of the inner and outer disc, will excite a slowly evolving bending wave in the outer disc. The torque from the stiff inner disc drives a retrograde,…
We analyze the evolution of stellar bars in galactic disks in mildly triaxial flat-core and cuspy CDM halos. We use tailored simulations of rigid and live halos which include the feedback from disk/bar onto the halo in order to test the…
`Conspiracy' between the dark and the baryonic mater prohibits an unambiguous decomposition of disc galaxy rotation curves into the corresponding components. Several methods have been proposed to counter this difficulty, but their results…
Aims. We aim to show how encounters with low-mass satellite galaxies may alter the bar formation in a Milky Way-like disc galaxy. Methods. We use high-resolution N-body simulations of a disc galaxy prone to mild bar instability. For…
The role of dark matter halos in galaxy disk evolution is reviewed, in particular the stabilisation of disks through self-gravity reduction, or the bar development through angular momentum exchange. Triaxial dark halos tend to weaken bars.…
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…
We show that bars in galaxy models having halos of moderate density and a variety of velocity distributions all experience a strong drag from dynamical friction unless the halo has large angular momentum in the same sense as the disk. The…
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}>…
We present observational evidence for the inhibition of bar formation in dispersion-dominated (dynamically hot) galaxies by studying the relationship between galactic structure and host galaxy kinematics in a sample of 257 galaxies between…
The problem of how some disk galaxies avoid forming bars remains unsolved. Many galaxy models having reasonable properties continue to manifest vigorous instabilities that rapidly form strong bars and no widely-accepted idea has yet been…
The saturation conditions for bending modes in inhomogeneous thin stellar disks that follow from an analysis of the dispersion relation are compared with those derived from $N$-body simulations. In the central regions of inhomogeneous…
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…
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…
Why do galactic bars rotate with high pattern speeds, when dynamical friction should rapidly couple the bar to the massive, slowly rotating dark halo? This longstanding paradox may be resolved by considering the dynamical interactions…