We present molecular gas-mass estimates for a sample of 13 local galaxies whose kinematic and star-forming properties closely resemble those observed in z approximate to 1.5 main-sequence galaxies. Plateau de Bure observations of the CO[1-0] emission line and Herschel Space Observatory observations of the dust emission both suggest molecular gas-mass fractions of similar to 20%. Moreover, dust emission modeling finds T-dust <30 K, suggesting a cold dust distribution compared to their high infrared luminosity. The gas-mass estimates argue that z similar to 0.1 DYNAMO galaxies not only share similar kinematic properties with high-z disks, but they are also similarly rich in molecular material. Pairing the gas-mass fractions with existing kinematics reveals a linear relationship between f(gas) and sigma/nu(c), consistent with predictions from stability theory of a self-gravitating disk. It thus follows that high gas-velocity dispersions are a natural consequence of large gas fractions. We also find that the systems with the lowest t(dep) (similar to 0.5 Gyr) have the highest ratios of sigma/nu(c) and more pronounced clumps, even at the same high molecular gas fraction.
|Number of pages||11|
|Journal||The Astrophysical Journal: an international review of astronomy and astronomical physics|
|Publication status||Published - 1 Sep 2017|