Galaxies 09: Assembly, Gas Content and Star Formation History of Galaxies

Carrie Bridge
Caltech

Evolution in the Merger Rate: Implications for Mass Assembly, Star Formation and AGN Activity

Using the Canada France Hawaii Telescope Legacy Survey (CFHTLS-Deep) we have developed a new physically-driven classification system to identify major galaxy-galaxy mergers based on the presence of tidal tails and bridges. These morphological features are robust signatures of recent or ongoing merger activity. This technique was applied to 2 sq. degrees (30,000 galaxies) of the (CFHTLS-Deep) and complied into the CFHTLS-Deep Catalog of Interacting Galaxies. The survey's depth, high image quality and Spitzer coverage have made it possible to probe the merger rate, and level of induced star formation and AGN activity throughout the merger sequence to $z\sim1$. I will present our following key findings: 1) strong evidence for an evolving merger rate, 2) mass assembly downsizing 3) star formation and AGN triggering in mergers and 4) a larger merger fraction in Luminous IR galaxies.

Return to the Conference Program