RSAA Colloquia / Seminars / Feast-of-Facts: Tuesday, 02 June 2015, 11:00-12:00; Duffield Lecture Theatre

Federico Lelli

"The close link between baryons and dark matter in disc galaxies"

Galaxies follow tight scaling relations linking their dynamical properties to their baryonic content. The study of these dynamical laws strongly constrains cosmological models of galaxy formation. I will present new results on the baryonic Tully-Fisher relation (BTFR), which links the total baryonic mass of a galaxy to its outer rotation velocity. I will discuss both successes and failures of LCDM models that attempt to reproduce the BTFR using gas outflows from stellar feedback. In particular, I will show that starburst dwarf galaxies in the nearby Universe provide no evidence for massive gas outflows. Finally, I will present new dynamical scaling laws that link the baryonic mass distribution of a galaxy to the detailed shape of its rotation curve: these relations can be thought of as local inner-galaxy counterparts of the BTFR.