Distant galaxies lack dark matter

Dark Matter in Elliptical Galaxies?

Dark Matter Halos around Galaxies

We present evidence that all galaxies, of any Hubble type and luminosity, bear the kinematical signature of a mass component distributed differently from the luminous matter. We review and/or derive the DM halo properties of galaxies of different morphologies: spirals, LSBs, ellipticals, dwarf irregulars and dwarf spheroidals. We show that the halo density profile Mh(x) = Mh(1) (1 + a ) x3 x2 +...

Molecular dark matter in galaxies

Context. Clouds containing molecular dark matter in quantities relevant for star formation may exist in minihaloes of the type of cold dark matter included in many cosmological simulations or in the regions of some galaxies extending far beyond their currently known boundaries. Aims. We have systematically explored parameter space to identify conditions under which plane-parallel clouds contain...

Baryonic Dark Matter in Galaxies

Cosmological nucleosynthesis calculations imply that many of the baryons in the Universe must be dark. We discuss the likelihood that some of these dark baryons may reside in the discs or halos of galaxies. If they were in the form of compact objects, they would then be natural MACHO candidates, in which case they are likely to be the remnants of a first generation of pregalactic or protogalact...

Dark matter distribution in dwarf spheroidal galaxies

We present predictions for the line-of-sight velocity dispersion profiles of dwarf spheroidal galaxies and compare them to observations in the case of the Fornax and Draco dwarfs. The predictions are made in the framework of standard dynamical theory of two-component (stars and dark matter) spherical systems with different velocity distributions. The stars are assumed to be distributed accordin...