Francisco Prada
IAA-CSIC
Spain
Abstract:
In this talk I will discuss the progress we have made on the knowledge of the properties of dark matter halos of isolated galaxies. Using the SDSS, we probe the halo mass distribution at large radii, by studying the motions of satellites around isolated galaxies. We find direct observational evidence of the dark matter density decline in the peripheral parts of galaxies as predicted by the LCDM paradigm; we also note that this result contradicts alternative theories of gravity such as MOND. We measure the virial mass-to-light and virial-to-stellar mass ratios of L* galaxies and study the evolution in their halo masses between z=1 and z=0 by combining data from the DEEP2 galaxy redshift survey and the SDSS. Other properties of satellites will be discussed. Finally, I will comment on the study we have performed on the outer structure of galactic dark matter halos and their mass growth in high-resolution cosmological simulations.