THE DARK-MATTER WORLD: ARE THERE DARK-MATTER GALAXIES?

Brane-world dark matter.

We show that, in the context of brane-world scenarios with low tension tau=f(4), massive brane fluctuations (branons) are natural dark matter candidates. We calculate the present abundances for both hot (warm) and cold branons in terms of the branon mass M and the tension scale f. The results are compared with the current experimental bounds on these parameters. We also study the prospects for ...

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...