Event Details

New insights into box/peanut bulge formation, at home and abroad

Abstract:

I demonstrate that all trends in chemistry, age and kinematic spaces of the Milky Way’s bulge stellar populations can be understood by a model of the bulge forming purely out of the evolution of the bar with only a ~1% addition of an accreted population. This accreted population is probably the stellar halo of the Milky Way. The trends are driven by a process we refer to as kinematic fractionation, because it separates out populations on the basis of their kinematics at the time of bar formation. I demonstrate some predictions of the model and present early evidence that external galaxies appear to follow similar trends. I also present evidence that the boxpeanut bulge fraction has evolved with redshift, with a characteristic mass that has remained invariant for the past 7 Gyr. Lastly I present recent work which is allowing us to rapidly explore stellar populations in models of B/P bulges.