A Comparison of Clusters of Galaxies with NBody Simulations.
Abstract
The threedimensional number density profiles, surface density profiles, the distribution of separation vectors and the velocity dispersion profiles of Wielen's Nbody simulations and statistical simulations generated via Monte Carlo techniques are compared with the same data profiles of observed clusters of galaxies. Computed masses for the simulations via the virial theorem (as customarily approximated for observed clusters) indicate that a virial excess approximately 2  5 can be obtained, but virial excesses 5 cannot be so explained. Since some observed clusters have virial excesses approximately 10, one must invoke hidden mass to account for the bulk of a cluster's mass. In addition, the general absence of mass segregation in rich clusters forces the conclusion that the missing mass must be in the form of many low mass intergalactic stars against which the visible galaxies are relaxing, delaying mass segregation among them.
 Publication:

Ph.D. Thesis
 Pub Date:
 1978
 Bibcode:
 1978PhDT.........6S
 Keywords:

 Physics: Astronomy and Astrophysics;
 Galactic Structure;
 Galaxies;
 Statistical Distributions;
 Statistical Tests;
 Density Distribution;
 Distribution (Property);
 Mathematical Models;
 Missing Mass (Astrophysics);
 Simulation;
 Astrophysics