%0 Generic %1 cortese2017shows %A Cortese, L. %A Catinella, B. %A Janowiecki, S. %D 2017 %K atomic fraction gas molecular turbulence %T ALMA shows that gas reservoirs of star-forming disks over the last 3 billion years are not predominantly molecular %U http://arxiv.org/abs/1709.07933 %X Cold hydrogen gas is the raw fuel for star formation in galaxies, and its partition into atomic and molecular phases is a key quantity for galaxy evolution. In this paper, we combine Atacama Large Millimeter Array and Arecibo single-dish observations to estimate the molecular-to-atomic hydrogen mass ratio for massive star-forming galaxies at $z\sim$ 0.2 extracted from the HIGHz survey, i.e., some of the most massive gas-rich systems currently known. We show that the balance between atomic and molecular hydrogen in these galaxies is similar to that of local main-sequence disks, implying that atomic hydrogen has been dominating the cold gas mass budget of star-forming galaxies for at least the last three billion years. In addition, despite harboring gas reservoirs that are more typical of objects at the cosmic noon, HIGHz galaxies host regular rotating disks with low gas velocity dispersions suggesting that high total gas fractions do not necessarily drive high turbulence in the interstellar medium.

@misc{cortese2017shows, abstract = {Cold hydrogen gas is the raw fuel for star formation in galaxies, and its partition into atomic and molecular phases is a key quantity for galaxy evolution. In this paper, we combine Atacama Large Millimeter Array and Arecibo single-dish observations to estimate the molecular-to-atomic hydrogen mass ratio for massive star-forming galaxies at $z\sim$ 0.2 extracted from the HIGHz survey, i.e., some of the most massive gas-rich systems currently known. We show that the balance between atomic and molecular hydrogen in these galaxies is similar to that of local main-sequence disks, implying that atomic hydrogen has been dominating the cold gas mass budget of star-forming galaxies for at least the last three billion years. In addition, despite harboring gas reservoirs that are more typical of objects at the cosmic noon, HIGHz galaxies host regular rotating disks with low gas velocity dispersions suggesting that high total gas fractions do not necessarily drive high turbulence in the interstellar medium.}, added-at = {2017-09-26T09:35:43.000+0200}, author = {Cortese, L. and Catinella, B. and Janowiecki, S.}, biburl = {https://www.bibsonomy.org/bibtex/24c42d4a58bca36291a7593ce641a2772/miki}, description = {[1709.07933] ALMA shows that gas reservoirs of star-forming disks over the last 3 billion years are not predominantly molecular}, interhash = {f9760eaadfbc6e7c962a217d3a690ec0}, intrahash = {4c42d4a58bca36291a7593ce641a2772}, keywords = {atomic fraction gas molecular turbulence}, note = {cite arxiv:1709.07933Comment: 8 pages, 3 figures, 1 table. Accepted for publication in ApJ Letters}, timestamp = {2017-09-26T09:35:43.000+0200}, title = {ALMA shows that gas reservoirs of star-forming disks over the last 3 billion years are not predominantly molecular}, url = {http://arxiv.org/abs/1709.07933}, year = 2017 }