3 November 2008
Genevieve Graves (UC Santa Cruz)
"Dissecting the Red Sequence: Star Formation Histories and Structure
of Early Type Galaxies"
I use 16,000 galaxy spectra from the Sloan Digital Sky Survey to probe the
varying stellar populations of early type galaxies throughout the
Fundamental Plane. Not only do early type galaxies span a 2-dimensional
family in the Fundamental Plane, they also span a 2-dimensional family in
star formation histories. In addition to known variations with galaxy mass,
I present evidence that stellar populations in these galaxies are intimately
linked with their central dark matter fraction, revealing a connection
between star formation history and structural evolution of the galaxy. I
discuss these results in the context of different models for galaxy
evolution in a hierarchical universe.