Related papers: Nearly Self-Consistent Disk-Bulge-Halo Models for …
The rotation dynamics of spiral galaxies is modeled using a sum of two mass distributions: a spherical bulge and a thin disk. The density functions representing these mass distributions are calculated from the total angular momentum of the…
Galaxies can form in a sufficiently deep gravitational potential so that efficient gas cooling occurs. We estimate that such potential is provided by a halo of mass $M \gtsim M_{c} \approx 7.0 \times 10^{12} ~ (\Delta_{c}(z)…
We present dynamically-determined rotation-curve mass decompositions of 30 spiral galaxies, which were carried out to test the maximum-disk hypothesis and to quantify properties of their dark-matter (DM) halos. We used measured vertical…
New information on the relations between the Galactic disks, the halo, and satellite galaxies is being obtained from elemental abundances of stars having metallicities in the range -1.5 < [Fe/H] < -0.5. The first results for a sample of 26…
Numerous observations have shown that the dark matter halo surface density, defined as the product of core radius and halo central density of cored dark matter haloes is nearly constant and independent of galaxy mass over a whole slew of…
The analysis of disk formation is based on the White & Rees (1978) picture, in which disk galaxies form by continuous cooling and accretion of gas within a merging hierarchy of dark matter halos. A simple Kennicutt law of star formation for…
In recent years, increasing attention has been devoted to semi empirical, data-driven models to tackle some aspects of the complex and still largely debated topic of galaxy formation and evolution. We here present a new semi empirical model…
We propose that the lower bound of the stellar radial velocity dispersion c_r of an equilibrium stellar disk is determined by the gravitational stability condition. We compared the estimates of stellar velocity dispersion at radii r>(1.5 -…
Galactic disks in triaxial dark matter halos become deformed by the elliptical potential in the plane of the disk in such a way as to counteract the halo ellipticity. We develop a technique to calculate the equilibrium configuration of such…
We investigate how stellar disks sustain their ultrathin structure throughout their evolution. We follow the evolution of ultrathin stellar disks with varying dark matter (DM) halo concentration ($c$) using collisionless $N$-body…
Recent JWST observations claim the existence of a significant fraction of bars in the kinematically hotter and thicker disk at high redshift Universe. These observations challenge the current understanding of disk stability in galaxies…
A considerable fraction of the massive quiescent galaxies at \emph{z} $\approx$ 2, which are known to be much more compact than galaxies of comparable mass today, appear to have a disk. How well can we measure the bulge and disk properties…
Galactic halo gas traces inflowing star formation fuel and feedback from a galaxy's disk and is therefore crucial to our understanding of galaxy evolution. In this review, we summarize the multi-wavelength observational properties and…
We developed a new selection method of halo stars in the phase-space distribution defined by the three integrals of motion in an axisymmetric Galactic potential, ($E$, $L_z$, $I_3$), where $I_3$ is the third integral of motion. The method…
Numerical models of disc galaxy formation predict the existence of extended, hot ( T~10^6 K) gas haloes around present day spirals. The X-ray luminosity of these haloes is predicted to increase strongly with galaxy mass. However, searches…
I highlight recent progress in our understanding of the origin of disk galaxy scaling laws in a hierarchically clustering universe. Numerical simulations of galaxy formation in Cold Dark Matter (CDM) dominated universes indicate that the…
We present an application of a new set of detailed, self-consistent, dynamical models for disc galaxies. We start from the hypothesis that each galaxy can be decomposed in a bulge, following the r^{1/4} law, and a disc with an exponential…
We estimated the Galactic model parameters from the SDSS data reduced for two fields in the anti-centre direction of the Galaxy, $l= 180^{o}$, and symmetric relative to the Galactic plane, $b=+45^{o}$ and $b=-45^{o}$. The large size of each…
We introduce a very simple model of a dark halo. It is a close relative of Hernquist's model, being generated by the same transformation but this time applied to the logarithmic potential rather than the point mass. The density is…
We investigate the evolution of star-forming gas-rich disks, using a 3D chemodynamical model including a dark halo, stars, and a two-phase interstellar medium with feedback processes from the stars. We show that galaxy evolution proceeds…