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Description
We present the HI mass inventory for the REsolved Spectroscopy Of a Local VolumE (RESOLVE) survey, a volume-limited, multi-wavelength census of >1500 z=0 galaxies spanning diverse environments and complete in baryonic mass down to dwarfs of ~10^9^M_{sun}_. This first 21cm data release provides robust detections or strong upper limits (1.4M_HI_<5%-10% of stellar mass M*) for ~94% of RESOLVE. We examine global atomic gas-to-stellar mass ratios (G/S) in relation to galaxy environment using several metrics: group dark matter halo mass M_h_, central/satellite designation, relative mass density of the cosmic web, and distance to the nearest massive group. We find that at fixed M*, satellites have decreasing G/S with increasing M_h_ starting clearly at M_h_~10^12^M_{sun}_, suggesting the presence of starvation and/or stripping mechanisms associated with halo gas heating in intermediate-mass groups. The analogous relationship for centrals is uncertain because halo abundance matching builds in relationships between central G/S, stellar mass, and halo mass, which depend on the integrated group property used as a proxy for halo mass (stellar or baryonic mass). On larger scales G/S trends are less sensitive to the abundance matching method. At fixed M_h_<=10^12^M_{sun}_, the fraction of gas-poor centrals increases with large-scale structure density. In overdense regions, we identify a rare population of gas-poor centrals in low-mass (M_h_<10^11.4^M_{sun}_) halos primarily located within ~1.5x the virial radius of more massive (M_h_>10^12^M_{sun}_) halos, suggesting that gas stripping and/or starvation may be induced by interactions with larger halos or the surrounding cosmic web. We find that the detailed relationship between G/S and environment varies when we examine different subvolumes of RESOLVE independently, which we suggest may be a signature of assembly bias.
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