Related papers: Orbital structure in barred spiral galaxies
We propose a new theory for the formation of rR_1 ring structures, i.e. for ring structures with both an inner and an outer ring, the latter having the form of ``8''. We propose that these rings are formed by material from the stable and…
We have done a detailed study on the structural and kinematical properties of lenticular and early- and late-type spiral galaxies with bars, aiming to explore the formation and evolution processes of stellar bars in galaxies, and their…
We present and discuss the orbital content of a rather unusual rotating barred galaxy model, in which the three-dimensional (3D) family, bifurcating from x1 at the 2:1 vertical resonance with the known "frown-smile" side-on morphology, is…
We analyze the orbital dynamics of spherical test bodies in ``black hole surrounded by dark matter halo'' spherically symmetric spacetimes. When the test body pulsates periodically (such as a variable star), altering its quadrupole tensor,…
We present an analysis of the orbital properties in 9 intermediate-redshifts cluster of the CNOC1 survey and we compare them to a control sample of 12 nearby clusters. Similar to the nearby elliptical galaxies, the bulge-dominated galaxies…
We develop a fourth-order numerical integrator to simulate the coupled spin and orbital motions of two rigid bodies having arbitrary mass distributions under the influence of their mutual gravitational potential. We simulate the dynamics of…
In the mean field limit, isolated gravitational systems often evolve towards a steady state through a violent relaxation phase. One question is to understand the nature of this relaxation phase, in particular the role of radial…
Bars in galaxies are mainly supported by particles trapped around stable periodic orbits. These orbits represent oscillatory motion with only one frequency, which is the bar driving frequency, and miss free oscillations. We show that a…
In our Solar system, spin-orbit resonances are common under Sun--planet, planet--satellite and binary asteroid configurations. In this work, high-order and secondary spin-orbit resonances are investigated by taking numerical and analytical…
This work is devoted to studying the influence of the bar on the orbital dynamics of globular clusters. The orbits of 45 globular clusters in the central galactic region with a radius of 3.5 kpc were analyzed using spectral dynamics methods…
I discuss results from the COSMOS survey, showing that the fraction of disc galaxies that is barred decreases considerably with look-back time from z ~ 0.2 to z ~ 0.8. This decrease is more important for small mass and low luminosity…
Recent analysis of stellar populations in barred galaxies have focused on the spatial distribution of stellar population ages and metallicities. However, barred galaxies are complex objects where dynamical instabilities play a leading role…
The dynamics of chaotic billiards is significantly influenced by coexisting regions of regular motion. Here we investigate the prevalence of a different fundamental structure, which is formed by marginally unstable periodic orbits and…
(Abridged) The Galactic bar causes a characteristic splitting of the disc phase space into regular and chaotic orbit regions which is shown to play an important role in shaping the stellar velocity distribution in the Solar neighbourhood. A…
We try to determine the Galactic structure by comparing the observed and modeled velocities of OB-associations in the 3 kpc solar neighborhood. We made N-body simulations with a rotating stellar bar. The galactic disk in our model includes…
As a first step towards a comprehensive investigation of stellar motions within globular clusters, we present here the results of a study of stellar orbits in a mildly triaxial globular cluster that follows a circular orbit inside a galaxy.…
Many barred galaxies exhibit upturns (shoulders) in their bar major-axis density profile. Simulation studies have suggested that shoulders are supported by looped $x_1$ orbits, occur in growing bars, and can appear after bar-buckling. We…
We compute the dispersion laws of chaotic periodic systems using the semiclassical periodic orbit theory to approximate the trace of the powers of the evolution operator. Aside from the usual real trajectories, we also include complex…
The orbits of stars in galaxies are generically chaotic: the chaotic behavior arises in part from the intrinsically grainy nature of a potential that is composed of point masses. Even if the potential is assumed to be smooth, however,…
Using a dataset of stars from a barred galaxy that provides instantaneous positions and velocities in the sky, we propose a method to identify its key structures, such as the central bar and spiral arms, and to determine the bar pattern…