A toy model of galaxy evolution inspired by stellar metallicity measurements from the SAMI survey

Wednesday December 2nd 2020 @12pm, Zoom Colloquium
Dr Sam Vaughan The University of Sydney

Email: sam.vaughan[at]sydney.edu.au


Nearby galaxies can be divided into two broad categories: those which have blue colours, disc-like morphologies and are forming stars; and those which are red, have spheroidal morphologies and have ceased their star formation. Explaining why this is the case is a key challenge of galaxy evolution theories, but a comprehensive theory of what causes galaxies to quench their star formation is still missing. I will discuss a toy model of quenching which successfully reproduces a number of important differences between quiescent and star-forming galaxies at redshift 0, including their different mass-metallicity relations and mass-size planes. This model was born out of my studies of stellar metallicities in the SAMI galaxy survey, and I will also give a brief summary of my metallicity measurements and some of the powerful statistical tools I’ve used in my analysis.