CfA OIR Division Lunch Talks
Thursday, September 11, 2008, 12:30 pm, Pratt Conference Room

Galaxy Mergers: Challenges to Conventional Wisdom

Dr. Jennifer Lotz (UCSC/Lick Observatory)

It remains unknown to what degree present-day galaxies are assembled discretely through the merger of pre-existing galaxies or through more continuous processes such as gas and dark-matter inflows. While the most obvious way to constrain the importance of galaxy mergers is to count the number of observed mergers, current observational estimates of the relative evolution in the merger fraction and the absolute galaxy merger rate vary wildly. I will discuss commonly-held assumptions about galaxy mergers and review the observational evidence for these assumptions. I will also discuss recent work using simulations of galaxy mergers to constrain the timescales for observing merger events and the absolute galaxy merger rate.