Related papers: Velocity Fields of Disk Galaxies

The study of the kinematics of galaxies within clusters or groups has the limitation that only one of the three velocity components and only two of the three spatial components of a galaxy position in six-dimensional phase space can…

We model the local stellar velocity field using position and velocity measurements for 4M stars from the second data release of Gaia. We determine the components of the mean or bulk velocity in ~27k spatially-defined bins. Our assumption is…

In a disc galaxy the distribution of azimuthal components of velocity is very skew. In the past this skewness has been modelled by superposed Gaussians. We use dynamical arguments to derive an analytic formula that can be fitted to observed…

I review progress in the past few years in studying the large-scale structure of the universe through redshift surveys of galaxies. Of the many statistical methods used to describe the galaxy distribution, I concentrate here on the power…

We consider the key problems related to measuring the mass of stellar disks and dark halos in galaxies and to explaining the observed properties of disks formed in massive dark halos.

Galaxies are observed to host magnetic fields with a typical total strength of around 15microgauss. A coherent large-scale field constitutes up to a few microgauss of the total, while the rest is built from strong magnetic fluctuations over…

We present radial velocities for approximately 40 stars in each of three optically obscured, off-axis, fields toward the Galactic bulge. Combined with the data presented by Blum et al. (1994), we now have mean radial velocities and radial…

We present high-accuracy rotation curves, which show a steep nuclear rise and high-velocity central rotation, followed by a broad maximum in the disk and flat part. We use the rotation curves to directly calculate the radial distribution of…

We present a method for recovering the distribution functions of edge-on thin axisymmetric disks directly from their observable kinematic properties. The most generally observable properties of such a stellar system are the line-of-sight…

The opacity of foreground spiral disks can be probed from the number of distant galaxies seen through them. To calibrate this number for effects other than the dust extinction, Gonzalez et al (1998) developed the "Synthetic Field Method". A…

Context: Planets are formed amidst young circumstellar disks of gas and dust. The latter is traced by thermal radiation, where strong asymmetric clumps were observed in a handful of cases. These dust traps could be key to understand the…

We present kinematic measurements of thin and thick disk components in a sample of nine edge-on galaxies. We extract stellar and ionized gas rotation curves at and above the galaxies' midplanes using the Ca II triplet absorption features…

The 2dF Galaxy Redshift Survey has obtained 135,000 redshifts for galaxies in two broad strips. Here we present the first results of a 3-dimensional search for galaxy clusters based on known 2-dimensional compilations. We derive new…

Magnetic field is ubiquitous in the Universe and it plays essential roles in various astrophysical phenomena, yet its real origin and evolution are poorly known. This article reviews current understanding of magnetic fields in the…

We assume that the individual stars which are located at the peripheral parts of the spiral galaxies are experiencing a drag force acting upon them radially. Such a force might be produced by some sort of a dynamically generated viscous…

Evolution of galaxies is one of the most actual topics in astrophysics. Among the most important factors determining the evolution are two galactic components which are difficult or even impossible to detect optically: the gaseous disks and…

Observations of turbulent velocity dispersions in the HI component of galactic disks show a characteristic floor in galaxies with low star formation rates and within individual galaxies the dispersion profiles decline with radius. We carry…

A general relativistic description of a disk rotating at constant angular velocity is given. It is argued that conceptually this direct approach poses fewer problems than the special relativistic one. For observers on the disk, the geometry…

We investigate the distribution of central velocity dispersions for quiescent galaxies in the SDSS at $0.03 \leq z \leq 0.10$. To construct the field velocity dispersion function (VDF), we construct a velocity dispersion complete sample of…

The formation and evolution of galactic disks is particularly important for understanding how galaxies form and evolve, and the cause of the variety in which they appear to us. Ongoing large surveys, made possible by new instrumentation at…