Seminar
Monday, July 23, 2012
3:10 pm - 4:00 pm
B5 Hearst Field Annex
Speaker/Performer: Katherine Alatalo
Molecular gas in massive early-type galaxies (ETGs) has been shown to be far more common than previously expected. In fact, at least 22% (60/259) contain a significant reservoir of molecular gas. To understand the presence and abundance of this unexpected gas, it is important to understand its timeline, where it originated, how it is evolving, and how long it will remain. An imaging survey of the molecular gas is important in addressing these issues. Here we present the molecular gas in the 31 brightest ETGs in the ATLAS3D survey, imaged with the Combined Array for Research for Millimeter Astronomy (CARMA), the largest systematic survey of the cold ISM in ETGs to date. ETGs feature a rich variety of gas configurations, including disks, extended molecular rings, spiral arms, and disrupted merger remnants, suggesting a melange of origins and fates. The menagerie observed by CARMA illustrates that the various paths molecular gas takes in ETGs is complex and nuanced, ranging from objects clearly undergoing an interaction to those with strangely quiescent origins. We also detail the rich molecular story of NGC 1266, its serendipitous discovery and how it plays host to an AGN-driven molecular outflow, potentially quenching all its star formation within the next 100 Myr. The ATLAS3D survey is a complete volume-limited survey of 259 massive (Mgal > 6e9 Msuns) ellipticals and lenticulars within 42 Mpc that will provide by far the best constraints on the dynamics and stellar populations, and thus the formation and evolution of local early-type galaxies through multi-wavelength studies.