Related papers: Simulating a slow bar in the low surface brightnes…
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…
We present dynamically-determined rotation-curve mass decompositions of 30 spiral galaxies, which were carried out to test the maximum-disk hypothesis and to quantify properties of their dark-matter (DM) halos. We used measured vertical…
We use N-body simulations of bar formation in isolated galaxies to study the effect of bulge mass and bulge concentration on bar formation. Bars are global disk instabilities that evolve by transferring angular momentum from the inner to…
The inner disc of the local group galaxy M33 appears to be in settled rotational balance, and near IR images reveal a mild, large-scale, two-arm spiral pattern with no strong bar. We have constructed N-body models that match all the…
The formation scenario for giant low surface brightness (gLSB) galaxies with discs as large as 100 kpc still remains unclear. These stellar systems are rare and very hard to observe, therefore a detailed insight on every additional object…
We present a two-step method to simulate and study non-circular motions in strongly barred galaxies. The first step is to constrain the initial parameters using a Bayesian analysis of each galaxy's azimuthally averaged rotation curve, the…
We analyse the rotation curves and gravitational stability of a sample of six bulgeless galaxies for which detailed images reveal no evidence for strong bars. We explore two scenarios: Newtonian dark matter models and MOdified Newtonian…
Low surface brightness galaxies are an excellent laboratory where stars and baryonic matter act as tracers of the gravitational potential of the dark matter halo. If dark matter is modeled as a perfect fluid, then spherically symmetric and…
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…
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…
Giant low surface brightness galaxies (gLSBGs) with dynamically cold stellar discs reaching the radius of 130 kpc challenge currently considered galaxy formation mechanisms. We analyse new deep long-slit optical spectroscopic observations,…
Simulations predict that bars in galaxies should slow down over time. This is often attributed to the exchange of angular momentum between the bar and other regions of the galaxy, such as the outer disc and dark matter halo, which implies…
Detailed neutral hydrogen observations have been obtained of the large barred spiral galaxy NGC 3992 and its three small companion galaxies, UGC 6923, UGC 6940, and UGC 6969. For the main galaxy, the HI distribution is regular with a low…
While bars are commonly observed in disk galaxies, the precise conditions governing their formation remain incompletely understood. To investigate these conditions, we perform a suite of N-body simulations of bulgeless disk galaxies with…
We perform a series of controlled N-body simulations of growing disc galaxies within non-growing, live dark matter haloes of varying mass and concentration. Our initial conditions include either a low-mass disc or a compact bulge. New…
We have used Spitzer images of a sample of 68 barred spiral galaxies in the local universe to make systematic measurements of bar length and bar strength. We combine these with precise determinations of the corotation radii associated with…
We use simulations to study the growth of a pseudobulge in an isolated thin exponential stellar disc embedded in a static spherical halo. We observe a transition from later to earlier morphological types and an increase in bar prominence…
Thanks to deep UV observations with GALEX and Swift, diffuse UV haloes have recently been discovered around galaxies. Based on UV-optical colours, it has been advocated that the UV haloes around spiral galaxies are due to UV radiation…
We measured the bar pattern speed, $\om$, of the SB0 galaxy NGC 1023 using the Tremaine-Weinberg (1984) method with stellar-absorption slit spectroscopy. The morphology and kinematics of the \hi gas outside NGC 1023 suggest it suffered a…
Isolated barred galaxies evolve by redistributing their internal angular momentum, which is emitted mainly at the inner disc resonances and absorbed mainly at the resonances in the outer disc and the halo. This causes the bar to grow…