RESOLVE and ECO: Toward a Complete Cosmic Mass Census

Sheila Kannappan
University of North Carolina, Chapel Hill
Tuesday, May 2, 2017
4:00 pm
NS2 1201


The REsolved Spectroscopy Of a Local VolumE (RESOLVE) survey is a volume-limited census of stellar, gas, and dynamical mass as well as star formation and merging within >50,000 cubic Mpc of the nearby cosmic web, reaching down to dwarf galaxies of baryonic (stellar + cold gas) mass ~10^9 Msun and up to galaxy groups/clusters and large-scale filaments, walls, and voids. RESOLVE is surrounded by the ~10x larger Environmental COntext (ECO) catalog, with matched custom photometry and environment metrics to enable analysis with greater statistical power. For the ~1500 galaxies in its two equatorial footprints, RESOLVE goes beyond ECO in providing deep, adaptive-sensitivity 21cm data and 3D optical spectroscopy. In this talk I will focus on initial results revealing the relationship of the multi-component cosmic mass census to group and larger scale environments. These results suggest that discrepancies between the observed mass census and that expected from standard dark matter theory are linked to the transition from isolated dwarf galaxies to small groups of galaxies, with associated cosmic gas heating and satellite destruction. I will argue that in this low-mass regime, alternative environment and star formation history metrics can clarify our physical understanding.

Michael Cooper