Department of Physics, Engineering Physics & Astronomy

Department of Physics, Engineering Physics & Astronomy
Department of Physics, Engineering Physics & Astronomy

Dark and Luminous Matter in Nearby Galaxies

Roelof de Jong
Space Telescope Science Institute

Wednesday, March 30, 2005
12:30 PM @ Stirling A

Abstract:

We have made remarkable progress in recent years in our understanding of galaxy formation and evolution. Deep, high redshift observations have constrained the star formation history of the Universe and have unveiled the evolution of galaxy morphologies. These observations have helped to build and solidify our current model of hierarchical structure and galaxy formation, in the favored Lambda Cold Dark Matter (CDM) paradigm. However, while very successful on scales of galaxies and larger, CDM faces a number of problems on smaller scales where "gastrophysics" comes into play. These problems relate to central density distribution of the dark matter halos, the angular momentum distribution of galaxy disks, and the lack of (stellar) substructure in galaxy sized halos. In my talk I will present observational constraints on the dark matter and angular momentum distribution problems, using a new technique to determine the stellar masses in disk galaxies. I will furthermore present new programs I have started to address the substructure problem by investigating stellar halos and tidal streamers.

Refreshments will be available after the talk in the lounge.