The evolution of the cold ISM following a starburst
Dust, Gas and Star Formation in Galaxies Throughout Cosmic Time
Kate Rowlands
University of St Andrews
Vivienne Wild, Nicole Nesvadba, Bruce Sibthorpe, Angela Mortier, Matt Lehnert, Elisabete da Cunha
One of the key problems in modern astrophysics is understanding how and why galaxies switch off their star formation, building the “red-sequence” that we observe in the local Universe. Post-starburst (“E+A”) galaxies, where a galaxy has recently undergone a massive starburst, are sufficiently common at z~1-2 that they may contribute significantly to the growth of the red-sequence at this important epoch (Wild et al. 2009). Understanding how star formation is shut off in these post-starbursts is important for understanding both their origins (e.g. gas-rich mergers or secular processes) and how rapidly, if at all, these galaxies will enter the red-sequence. We present the evolution of the molecular gas and dust properties of a sample of low-redshift post-starburst galaxies selected to span an age sequence from ongoing starburst to 1 Gyr after the starburst ended (Rowlands et al. 2015). Our results show that although a strong starburst may cause the galaxy to ultimately have a lower specific SFR and be of an earlier morphological type, multiple such episodes may be needed to complete migration of the galaxy from the blue- to red-sequence.
13:30 - 15:00