Related papers: Disk-galaxy density distribution from orbital spee…
Given the dimensions (including thickness) of an axisymmetric galaxy, Newton's law is used in integral form to find the density distributions required to match a wide range of orbital speed profiles. Newton's law is not modified and no dark…
Given the dimensions (including thickness) of a galaxy, and its rotation profile, a method is shown that finds the mass and density distributions in the defined envelope that will cause that rotation profile with near-exact speed matches.…
Given the dimensions (including thickness) and rotation speeds for an axisymmetric galaxy, a closed-loop iterative method is designed to find the total mass, density, and surface-mass density (SMD)distributions. There is no need for…
An accurate computational method is presented to determine the mass distribution in a rotating thin-disk galaxy from given rotation curve by applying Newtonian dynamics for an axisymmetrically rotating thin disk of finite size with or…
The gravitational potential and the gravitational rotation field generated by a thin-disk mass distribution with exponential density are considered in the case when the force between any two mass elements is not the usual Newtonian one, but…
By numerically solving the mass distribution in a rotating disk based on Newton's laws of motion and gravitation, we demonstrate that the observed flat rotation curves for most spiral galaxies correspond to exponentially decreasing mass…
The measured rotation velocity profiles of mature spiral galaxies are successfully described with a gravitational model consisting of a thin axisymmetric disk of finte radius. The disk is assumed uniformly thin but with variable radial mass…
We present an efficient, robust computational method for modeling the Newtonian dynamics for rotation curve analysis of thin-disk galaxies. For a disk galaxy with a typical flat rotation curve, our modeling results show that the surface…
Observations reveal that mature spiral galaxies consist of stars, gases and plasma approximately distributed in a thin disk of circular shape, usually with a central bulge. The rotation velocities quickly increase from the galactic center…
An efficient method is developed which allows the calculation of distributions of the surface density in the equilibrium disk configurations with an isolated point mass at the center corresponding to known distributions of the angular…
We use the rotation curves of more than 100 disk galaxies to examine whether the structure of their surrounding dark halos is consistent with the universal density profile proposed by Navarro, Frenk & White (NFW profiles). Rotation curve…
This paper continues previous work on a novel alternative model of gravity, based on the theory of fractional-dimension spaces applied to Newton's law of gravitation. In particular, our Newtonian Fractional-Dimension Gravity is now applied…
An impact model of gravity designed to emulate Newton's law of gravitation is applied to the radial acceleration of disk galaxies. Based on this model (Wilhelm et al. 2013), the rotation velocity curves can be understood without the need to…
The distributions of normal matter and of dark matter in the Galaxy are coupled to each other as they both move in the common gravitational potential. In order to fully exploit this interplay and to derive the various properties of dark…
We review the most recent evidence for the amazing properties of the density distribution of dark matter around spiral galaxies. Their rotation curves, coadded according to the galaxy luminosity, conform to an universal profile which can be…
A pilot experiment suitable to test Newton's law of gravity down to the regime of acceleration typical of galaxies has been carried out in Omega Centauri. Stars in the extreme periphery of this globular cluster are used as test particles…
We consider the consequences of applying general relativity to the description of the dynamics of a galaxy, given the observed flattened rotation curves. The galaxy is modeled as a stationary axially symmetric pressure-free fluid. In spite…
The thickness of the equilibrium isothermal gaseous layers and their volume densities \rho_{gas}(R) in the disc midplane are calculated for 7 spiral galaxies (including our Galaxy) in the frame of self-consistent axisymmetric model. Local…
The self-consistent spatial distribution of particles of Galactic dark matter is derived including their own gravitational potential, as also that of the visible matter of the Galaxy. In order to reproduce the observed rotation curve of the…
We derive a formula for the velocity distribution of an axially symmetric galaxy where the mass density is corrected using the mass formula from special relativity. We take some reasonable test mass densities and numerically compute the…