相关论文: Mass distribution in rotating thin-disk galaxies a…
The spiral galaxy NGC 6503 exhibits a regular kinematical structure except for a remarkable drop of the stellar velocity dispersion values in the central region. To investigate the dynamics of the disc a theoretical framework has been…
We show that the stellar surface-brightness profiles in disc galaxies---observed to be approximately exponential---can be explained if radial migration efficiently scrambles the individual stars' angular momenta while conserving the…
Conditions for the fragmentation of expanding shells due to gravitational instability are discussed. The self-similar analytical solution is compared with the results of 3-dimensional computer simulations for the expansion into homogeneous…
We study dynamical models for elliptical galaxies, deriving the projected kinematic profiles in a form that is valid for general surface-brightness profiles and (spherical) total mass profiles, without the need for any explicit…
In this work, we propose a modified Newton dynamics (MOND) model to study the rotation curves of galaxies. The model is described by an arctangent interpolating function and it fits the rotation curves of several galaxies without invoking…
In the classical theory of thin disc accretion discs, the constraints of mass and angular momentum conservation lead to a diffusion-like equation for the turbulent evolution of the surface density. Here, we revisit this problem, extending…
Mass models for a sample of 18 late-type dwarf and low surface brightness galaxies show that in almost all cases the contribution of the stellar disks to the rotation curves can be scaled to explain most of the observed rotation curves out…
We continue our analysis of Newtonian Fractional-Dimension Gravity, an extension of the standard laws of Newtonian gravity to lower dimensional spaces including those with fractional (i.e., non-integer) dimension. We apply our model to…
We find the dispersion relation for tightly wound spiral density waves in the surface of rotating, self-gravitating disks in the framework of Modified Gravity (MOG). Also, the Toomre-like stability criterion for differentially rotating…
Observations show that the slope of the inner part of the H$\alpha$/[NII] rotation curves of disk galaxies is depressed by extinction: at fixed luminosity, the observed slope is in fact seen to depend on the disk inclination to the line of…
The colour and metallicity gradients observed in spiral galaxies suggest that the mass-to-light ratio (M*/L) of the stellar disc is a function of radius. This is indeed predicted by chemo-photometric models of galactic discs. We investigate…
Observations of disk galaxies at z~2 have demonstrated that turbulence driven by gravitational instability can dominate the energetics of the disk. We present a 1D simulation code, which we have made publicly available, that economically…
We report idealized simulations that mimic the growth of galaxy disks embedded in responsive halos and bulges. The disks manifested an almost overwhelming tendency to form strong bars that we found very difficult to prevent. We found that…
In this paper we report a new method for determining the thickness of the non-edge-on disk galaxies. Our method is based on the observation comparing with the theoretical researches of the distribution of the vertical velocity dispersion,…
The formation of disk galaxies is one of the most outstanding problems in modern astrophysics and cosmology. We review the progress made by numerical simulations carried out on large parallel supercomputers. Recent progress stems from a…
A general inversion technique for the recovery of the underlying distribution function for observed galactic disks is presented and illustrated. Under the assumption that these disks are axi-symmetric and thin, the proposed method yields…
The mass distribution of compact objects provides a fossil record that can be studied to uncover information on the late stages of massive star evolution, the supernova explosion mechanism, and the dense matter equation of state.…
The information contained in galactic rotation curves is examined under a minimal set of assumptions. If emission occurs from stable circular geodesic orbits of a static spherically symmetric field, with information propagated to us along…
We present a new analytical solution to the steady-state distribution of stars close to a central supermassive black hole of mass $M_{\bullet}$ in the center of a galaxy. Assuming a continuous mass function of the form $dN/dm \propto…
A general method is presented for constructing distribution functions for flat systems whose surface density and Toomre's Q number profile is given. The purpose of these functions is to provide plausible galactic models and assess their…