Department of Physics, Engineering Physics & Astronomy

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

Cosmology in Our Backyard: The Origin and Structure of Disk Galaxies

Stéphane Courteau
University of British Columbia

Thursday, September 18, 2003
11:30 AM @ Stirling C

Abstract:

It is a surprising fact that we have not yet achieved a satisfactory understanding of the structure of galaxies, even the Galaxy that is our home.

The distribution of stars and gas in galaxies depends not only on the mass and angular momentum initial conditions, but also on the physics of the birth and death of stars, the properties of"(cold) dark matter" not yet observed in the laboratory, and the merger history of protogalaxies over cosmological time. N-body simulations based on Cold Dark Matter cosmologies predict cuspy density profiles of dark matter halos and a low fraction of baryonic to dark matter content even in the visible parts of disk galaxies, yet neither of these predictions have been confirmed at present. The impact of gas cooling and shock heating on the evolution of galaxy disks is also poorly known. We can gain insight into these critical issues with dynamical information, stellar colours, spectral line strengths to estimate abundances and star formation histories, and scaling relations of disk galaxies.

I will discuss how we can exploit the wealth of information in our (cosmological) backyard to probe the baryonic and dark matter content, structure, and evolution of spiral galaxies.

Dr. Courteau is a candidate for the Astrophysics position in the Physics Department.

Refreshments will be available after the talk.