1. The ALMA Spectroscopic Survey in the HUDF: the Molecular Gas Content of Galaxies and Tensions with IllustrisTNG and the Santa Cruz SAM
- Author
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Dylan Nelson, Jorge González-López, Paulo C. Cortes, Thierry Contini, Paul van der Werf, Mark Vogelsberger, Hans-Walter Rix, Mark Swinbank, Emanuele Daddi, Fabian Walter, Rachel S. Somerville, Tanio Díaz-Santos, Elisabete da Cunha, L. Y. Aaron Yung, Rob Ivison, Jeff Wagg, Roberto Decarli, R. J. Bouwens, Manuel Aravena, Axel Weiss, Leindert Boogaard, Olivier Le Fevre, Lars Hernquist, Chris Carilli, Pierre Cox, Benedikt Diemer, Federico Marinacci, Gergö Popping, Dominik Riechers, Annalisa Pillepich, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, Rutgers University [Camden], Rutgers University System (Rutgers), Max-Planck-Institut für Astronomie (MPIA), Max-Planck-Gesellschaft, National Radio Astronomy Observatory [Socorro] (NRAO), National Radio Astronomy Observatory (NRAO), Cornell University [New York], Millimeter and Submillimeter Astronomy, Max-Planck-Institut für Radioastronomie (MPIFR), Leiden Observatory [Leiden], Universiteit Leiden, Institut de recherche en astrophysique et planétologie (IRAP), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Institut d'Astrophysique de Paris (IAP), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'Astrophysique de Marseille (LAM), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS), Institute for Computational Cosmology (ICC), Durham University, Smithsonian Institution-Harvard University [Cambridge], Universiteit Leiden [Leiden], Institut national des sciences de l'Univers (INSU - CNRS)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Observatoire Midi-Pyrénées (OMP), Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Université Fédérale Toulouse Midi-Pyrénées-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Météo France-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Popping G., Pillepich A., Somerville R.S., Decarli R., Walter F., Aravena M., Carilli C., Cox P., Nelson D., Riechers D., Weiss A., Boogaard L., Bouwens R., Contini T., Cortes P.C., Cunha E.D., Daddi E., Diaz-Santos T., Diemer B., Gonzalez-Lopez J., Hernquist L., Ivison R., Fevre O.L., Marinacci F., Rix H.-W., Swinbank M., Vogelsberger M., Werf P.V.D., Wagg J., Yung L.Y.A., Rutgers University, Cornell University, Centre National de la Recherche Scientifique (CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS), Département d'Astrophysique (ex SAP) (DAP), Institut de Recherches sur les lois Fondamentales de l'Univers (IRFU), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris-Saclay, Royal Observatory Edinburgh (ROE), and University of Edinburgh
- Subjects
Physics ,COSMIC cancer database ,010504 meteorology & atmospheric sciences ,Stellar mass ,[SDU.ASTR]Sciences of the Universe [physics]/Astrophysics [astro-ph] ,FOS: Physical sciences ,Astronomy and Astrophysics ,Astrophysics ,Galaxies: Evolution-galaxies: Formation-galaxies: High-redshift-galaxies: Ism-ism: Molecules ,Hubble Ultra-Deep Field ,Astrophysics - Astrophysics of Galaxies ,01 natural sciences ,Galaxy ,[SDU]Sciences of the Universe [physics] ,Space and Planetary Science ,Astrophysics of Galaxies (astro-ph.GA) ,0103 physical sciences ,Content (measure theory) ,Galaxy formation and evolution ,010303 astronomy & astrophysics ,ComputingMilieux_MISCELLANEOUS ,Density evolution ,0105 earth and related environmental sciences - Abstract
The ALMA Spectroscopic Survey in the Hubble Ultra Deep Field (ASPECS) provides new constraints for galaxy formation models on the molecular gas properties of galaxies. We compare results from ASPECS to predictions from two cosmological galaxy formation models: the IllustrisTNG hydrodynamical simulations and the Santa Cruz semi-analytic model (SC SAM). We explore several recipes to model the H$_2$ content of galaxies, finding them to be consistent with one another, and take into account the sensitivity limits and survey area of ASPECS. For a canonical CO-to-H$_2$ conversion factor of $��_{\rm CO} = 3.6\,\rm{M}_\odot/(\rm{K}\,\rm{km/s}\,\rm{pc}^{2})$ the results of our work include: (1) the H$_2$ mass of $z>1$ galaxies predicted by the models as a function of their stellar mass is a factor of 2-3 lower than observed; (2) the models do not reproduce the number of H$_2$-rich ($M_{\rm H2} > 3\times 10^{10}\,\rm{M}_\odot$) galaxies observed by ASPECS; (3) the H$_2$ cosmic density evolution predicted by IllustrisTNG (the SC SAM) is in tension (only just agrees) with the observed cosmic density, even after accounting for the ASPECS selection function and field-to-field variance effects. The tension between models and observations at $z>1$ can be alleviated by adopting a CO-to-H$_2$ conversion factor in the range $��_{\rm CO} = 2.0 - 0.8\,\rm{M}_\odot/(\rm{K}\,\rm{km/s}\,\rm{pc}^{2})$. Additional work on constraining the CO-to-H$_2$ conversion factor and CO excitation conditions of galaxies through observations and theory will be necessary to more robustly test the success of galaxy formation models., Re-submitted to ApJ after addressing the first round of comments by the referee, other comments welcome
- Published
- 2019