SHOCKED POSTSTARBURST GALAXY SURVEY. II. the MOLECULAR GAS CONTENT and PROPERTIES of A SUBSET of SPOGs

We present CO(1-0) observations of objects within the Shocked POststarburst Galaxy Survey taken with the Institut de Radioastronomie Millimtrique 30 m single dish and the Combined Array for Research for Millimeter Astronomy interferometer. Shocked poststarburst galaxies (SPOGs) represent a transitioning population of galaxies, with deep Balmer absorption (EWHd > 5 A), consistent with an intermediate-age (A-star) stellar population, and ionized gas line ratios inconsistent with pure star formation. The CO(1-0) subsample was selected from SPOGs detected by the Wide-field Infrared Survey Explorer with 22 μm flux detected at a signal-to-noise ratio (S/N) > 3. Of the 52 objects observed in CO(1-0), 47 are detected with S/N > 3. A large fraction (37%- 46% ± 7%) of our CO-SPOG sample were visually classified as morphologically disrupted. The H2 masses detected were between 108.7-10.8 Ṁ, consistent with the gas masses found in normal galaxies, though approximately an order of magnitude larger than the range seen in poststarburst galaxies. When comparing the 22 μm and CO(1-0) fluxes, SPOGs diverge from the normal star-forming relation, having 22 μm fluxes in excess of the relation by a factor of 〈 ∈;MIR〉 =4.91₊₀₄₂ ^-0.39 0.42, suggestive of the presence of active galactic nuclei (AGNs). The Na I D characteristics of CO-SPOGs show that it is likely that many of these objects host interstellar winds. Objects with large Na I D enhancements also tend to emit in the radio, suggesting possible AGN driving of neutral winds.