相关论文: Gasflows in Barred Galaxies with Big Orbital Loops…
We use a Cartesian grid to simulate the flow of gas in a barred Galactic potential and investigate the effects of varying the sound speed in the gas and the resolution of the grid. For all sound speeds and resolutions, streamlines closely…
We investigate stationary gas flows in a fixed, rotating barred potential. The gas is assumed to be isothermal with an effective sound speed c_s, and the equations of motion are solved with smoothed particle hydrodynamics (SPH). Since the…
Context. We study a series of response models to investigate the formation of specific morphological features in the central 1 kpc region of the gas component in barred spiral galaxies. Aims. We aim to understand how structures, such as…
With a help of hydrodynamical models, we explore fundamental modes of gas flow in central parts of a galaxy potential with non-axisymmetric perturbations of various strengths. Our grid-based algorithm allows us to get a detailed picture of…
We report here results of high-resolution hydrodynamical simulations of gas flows in barred galaxies, with a focus on gas dynamics in the central kiloparsec. In a single bar with an Inner Lindblad Resonance, we find either near-circular…
Context: One of the ways to determine the contribution of the dark halo to the gravitational potential of a galaxy is the study of non-circular (streaming) motions and the associated gas shocks in the bar region. These motions, determined…
Galaxy-galaxy interactions and large scale galaxy bars are usually considered as the two main mechanisms for driving gas to the centres of galaxies. By using large samples of galaxy pairs and visually classified bars from the Sloan Digital…
In the present work we have developed a three-dimensional gravitational model of barred galaxies, in order to study orbital and escape dynamics of the stars inside their central barred region. Our gravitational model is composed of four…
Bars in galaxies are mainly supported by particles trapped around closed periodic orbits. These orbits respond to the bar's forcing frequency only and lack free oscillations. We show that a similar situation takes place in double bars:…
The escape dynamics of the stars in a barred galaxy composed of a spherically symmetric central nucleus, a bar, a flat thin disk and a dark matter halo component is investigated by using a realistic three degrees of freedom (3-dof)…
The pattern speeds of spiral galaxies are closely related to the flow of material in their disks. Flows that follow the `precessing ellipses' paradigm (see e.g., Kalnajs 1973) are likely associated with slowly rotating spirals, which have…
In this paper we use the two-dimensional (2D) version of a new analytical gravitational model in order to explore the orbital as well as the escape dynamics of the stars in a barred galaxy composed of a spherically symmetric central…
We use hydrodynamic simulations to investigate nonlinear gas responses to an imposed stellar spiral potential in disk galaxies. The gaseous medium is assumed to be infinitesimally thin, isothermal, and unmagnetized. We consider various…
We present new gas flow models for the Milky Way inside the solar circle. Using a mass model derived from the COBE/DIRBE maps and clump giant star counts, and using a parametric model for the spiral arm pattern in the disk, we calculate the…
I briefly review the properties of the gas flow in and around the region of the bar in a disc galaxy and discuss the corresponding inflow and the loci of star formation. I then review the flow of gas in barred galaxies which have an…
We study the baryon mass fraction in a set of hydrodynamical simulations of galaxy clusters performed using the Tree+SPH code GADGET-2. We investigate the dependence of the baryon fraction upon the radiative cooling, star formation,…
The ambient hot intra-halo gas in clusters of galaxies is constantly fed and stirred by in-falling galaxies, a process that can be studied in detail with cosmological hydro- dynamical simulations. However, different numerical methods yield…
In a series of papers, we propose a theory to explain the formation and properties of rings and spirals in barred galaxies. The building blocks of these structures are orbits guided by the manifolds emanating from the unstable Lagrangian…
In an effort to better understand the formation and evolution of barred galaxies, we have examined the properties of equatorial orbits in the effective potential of one model of a rapidly rotating, steady-state gas-dynamical bar that has…
The morphology of a galaxy stems from secular and environmental processes during its evolutionary history. Thus galaxy morphologies have been a long used tool to gain insights on galaxy evolution. We visually classify morphologies on…