JAO Colloquium

Title:  PHANGS-ALMA: Our First Cloud-Scale Survey of Molecular Gas in Galaxies

– Abstract: I will present "PHANGS-ALMA" a multi-cycle ALMA survey of 90 nearby galaxies built around an ALMA Large Program. Leveraging ALMA's amazing combination of resolution, sensitivity, and mapping speed, PHANGS-ALMA mapped the CO 2-1 emission, our basic tracer of molecular gas in galaxies, at 1" = 50-150 pc resolution scales across essentially all accessible very nearby star-forming galaxies. This resolution represents a major leap forward because, for the first time, PHANGS-ALMA resolves the molecular gas across whole galaxies into individual star-forming molecular clouds, giving access to the demographics, life cycle, and properties of tens of thousands of molecular clouds across a representative set of z=0 galaxies. I will give an overview of the motivation and execution of the survey, and then highlight results on the demographics of molecular clouds, kinematics and structure of gas at high resolution, and the links between molecular gas and star formation. I will also highlight a few aspects of our technical work that may be of interest to the expert audience at JAO.