Speaker
Ben Keller
(McMaster University)
Description
M* galaxies, with halo masses ~10^12 Msun, live in an interesting part of parameter space. Not only are they
the "turnover" in the galaxy mass Schecter function, they also have the highest stellar mass (and baryon)
fraction, very low bulge-to-disk ratios, and dominate the star formation of the epoch they live in. In this talk I will
present the results of a sample of 18 cosmological M* galaxies, simulated using the state-of-the-art superbubble
method for handling feedback from Type II Supernovae. I will show that the key to obtaining a realistic stellar
mass to halo mass relation (SMHMR) is preventing the runaway growth of a massive bulge by driving outflows
with large mass-loadings. If this happens, SN feedback alone can no longer effectively drive outflows from the
galaxy, and star formation becomes unregulated. This is a key piece of evidence that the peak of the SMHMR
is due to the shut down of SN regulation and the beginning of AGN regulation in more massive halos. I will also
show how the interaction between hot outflows and the disk ISM, together with the potential well they live within,
sets how much mass is entrained in a galactic wind/fountain, and how this can halt SN-driven winds in high-
mass galaxies.
Author
Ben Keller
(McMaster University)
Co-author
Dr
James Wadsley
(McMaster University)
