xGASS: The spatial distribution of quenching in gas-rich Green Valley galaxies

The population of so-called Green Valley galaxies between the star-forming Main Sequence and the red sequence has surprisingly diverse cold gas properties. The xGASS sample has shown that Green Valley galaxies can be equally (or more) gas-rich as those in the main sequence, with longer gas depletion timescales, on average. We have undertaken a comprehensive narrow-band H-alpha imaging campaign for xGASS galaxies in the Green Valley. These H-alpha images directly quantify the amount and spatial distribution of recent star formation activity. We compare Green Valley and Main Sequence galaxies, distinguishing between those with and without significant reservoirs of cold gas. Our results suggest that some gas-rich Green Valley galaxies have spatially extended star formation and may be forming stars inefficiently in their outer disks. By comparing the recent star formation from H-alpha with archival ultra-violet images, we construct simple star formation histories for these galaxies. This analysis of the spatial distribution of star formation across the Green Valley will help understand why and how long gas-rich galaxies can survive in the Green Valley.