Radiation in Galaxy Formation and Evolution:  A tale of 7 dwarfs

James Wadsley,
McMaster University

Abstract:

_{Galaxies are not as isolated as they may appear: they exchange huge amounts of material with their nearby environment.  Even typical disk galaxies contain only 1/4 the expected stars and gas (baryons) expected from their dark matter.   Smaller galaxies can contain far less.    These exchanges have many consequences, such as polluting nearby space with hot gas and metals, which can be observed as quasar absorption lines out to large distances.   There is a long list of ideas for how galaxies limit their gas and star content,  including pushing gas out with stellar feedback such as supernovae,  AGN, cosmic rays and radiation driven processes.     Violent outflows even have the potential to modify the dark matter profile.  There are also more subtle mechanisms, such as not letting the gas cool and accrete in the first place.   I present recent simulations using on-the-fly radiative transfer to better model gas in and around galaxies and the consequences for their evolution.    I show the impact on dwarf galaxies in particular.}

Timbits, coffee, tea will be served in STI A before the colloquium.