RSAA Colloquia / Seminars / Feast-of-Facts: Friday, 07 October 2016, 14:00-14:20; Duffield Lecture Theatre

Darshan Kakkad

"ALMA observations of cold molecular gas in AGN hosts at high redshift - Evidence of AGN feedback ?"

The high redshift regime presents an interesting laboratory to test radiative feedback from AGNs owing to their peak accretion density during this epoch. Observational efforts are underway to quantify the impact of AGN feedback, if it exists, on their host galaxies. We will present the first statistically sound investigation with ALMA of the molecular gas content, CO(2-1), in a sample AGNs hosted in main-sequence galaxies at z~1.5. We compare the molecular gas content of these AGN hosts with a sample of inactive galaxies matched in redshift, stellar mass and star formation rate. Our results indicate a statistically significant depletion of molecular gas in AGN hosts with respect to the inactive comparison sample. We will discuss the implication of these observations on the impact that AGN feedback may have on the star-formation efficiency of z>1 galaxies.