Therotation curveof a galaxy with an equatorial plane (for example a spiral galaxy has its spiral arms lying roughly in such a plane) is the plot of tangential velocity against distance from the centre for a particle (star or similar) moving in the equatorial plane. In practice it is not...
The rotation curve data for spiral galaxies are consistent with the dark matter distributed in their halo. This dark halo constitutes much of the galaxy’s total mass. All baryonic matter (stars, star clusters, ISM, etc.) are held together by the gravitational potential of this dark matter ha...
(2.18) were chosen so that the velocity curve becomes flat. Our choice is µ = 1 50 1 kpc , (2.24) y=3. (2.25) We thus obtain the square of the rotation velocity as a function of the distance r from the center of galaxy by rg 2π v2(r) = σ0 4π r dr′ dθ′r′e...
galaxies : spiralEDGE-ON GALAXIESRADIAL DISTRIBUTIONSNEARBY GALAXIESSTAR-FORMATIONSTELLAR DISCSDUSTThe observed anti-correlation between the inclination and the slope of the innermost part of the rotation curve can be attributed to dust extinction. However, the implied central face-on opacity of tau =...
A sample of 22 spiral galaxy rotation curves, measured in the 21 cm line of neutral hydrogen, is considered in the context of Milgrom's modified dynamics (MOND). Combined with the previous, highly selected sample of Begeman et al., this constitutes the current total sample of galaxies with ...
Our direct method rests on the simulation of a spiral galaxy by a disc of N massive bodies distributed with an axial symmetry. As these bodies follow a given curve of rotation, then the balance of the radial forces between N bodies leads to a set of linear equations (the unknown are ...
flatgalaxy. •Severalrotationcurveofedge-ongalaxiesappearsignsoflargeextinc- tionintheplaneofthegalaxyspiralarms,whichisintersected by the line of sight at small angles. • Nevertheless, the galaxies under study show a close correlation between the rotation amplitudes, as inferred from the H α...
You might want to look up the history of that to see exactly what they did to arrive at those numbers. Part of it might have even been theoretical models of the galaxy's rotational curve, and may (or may not) have taken into account the postulated Dark Matter effects. #4 yuzameh ...
(35 A/mm in the 6450-6800 A range and 92 A/mm in the 3700-5100 A range) yield a linear rotation curve for the peculiar edge-on galaxy NGC 2976; the curve is slightly steeper for the NW region than for the SE one; this leads to a very small mass of two billion solar masses. ...
The rotation curve of the dwarf galaxy UGC 2259 in the radial range 0.25 - 2.5 kpc was obtained from two separate data cubes. A disk model, with mass following the radial luminosity profile, cannot produce the observed rotation curve, but a satisfactory fit is obtained by adding a dark halo...