The Structure of Cold Dark Matter Halos

摘要: We use N-body simulations to investigate the structure of dark halos in standard Cold Dark Matter cosmogony. Halos are excised from cosmologically representative regions and resimulated individually at high resolution. study objects with masses ranging those dwarf galaxy rich clusters. The spherically averaged density profiles all our can be fit over two decades radius by scaling a simple ``universal'' profile. characteristic overdensity halo, or equivalently its concentration, correlates strongly halo mass way which reflects dependence epoch formation. Halo approximately isothermal large range radii, but significantly shallower than $r^{-2}$ near center steeper virial radius. Matching observed rotation curves disk galaxies requires mass-to-light ratios increase systematically luminosity. Further, it suggests that bright depend only weakly on luminosity have circular velocities lower speed. This may explain why dynamics uncorrelated samples binary satellite/spiral systems. For clusters, models consistent both presence giant arcs intracluster medium, they suggest explanation for disparate estimates cluster core radii found previous authors. Our results also highlight shortcomings CDM model. too concentrated parameters inferred irregulars, predicted abundance is larger galaxies.