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Title: COMBINED CO AND DUST SCALING RELATIONS OF DEPLETION TIME AND MOLECULAR GAS FRACTIONS WITH COSMIC TIME, SPECIFIC STAR-FORMATION RATE, AND STELLAR MASS

Abstract

We combine molecular gas masses inferred from CO emission in 500 star-forming galaxies (SFGs) between z = 0 and 3, from the IRAM-COLDGASS, PHIBSS1/2, and other surveys, with gas masses derived from Herschel far-IR dust measurements in 512 galaxy stacks over the same stellar mass/redshift range. We constrain the scaling relations of molecular gas depletion timescale (t {sub depl}) and gas to stellar mass ratio (M {sub mol} {sub gas}/M{sub *} ) of SFGs near the star formation ''main-sequence'' with redshift, specific star-formation rate (sSFR), and stellar mass (M{sub *} ). The CO- and dust-based scaling relations agree remarkably well. This suggests that the CO → H{sub 2} mass conversion factor varies little within ±0.6 dex of the main sequence (sSFR(ms, z, M {sub *})), and less than 0.3 dex throughout this redshift range. This study builds on and strengthens the results of earlier work. We find that t {sub depl} scales as (1 + z){sup –0.3} × (sSFR/sSFR(ms, z, M {sub *})){sup –0.5}, with little dependence on M {sub *}. The resulting steep redshift dependence of M {sub mol} {sub gas}/M {sub *} ≈ (1 + z){sup 3} mirrors that of the sSFR and probably reflects the gas supplymore » rate. The decreasing gas fractions at high M{sub *} are driven by the flattening of the SFR-M {sub *} relation. Throughout the probed redshift range a combination of an increasing gas fraction and a decreasing depletion timescale causes a larger sSFR at constant M {sub *}. As a result, galaxy integrated samples of the M {sub mol} {sub gas}-SFR rate relation exhibit a super-linear slope, which increases with the range of sSFR. With these new relations it is now possible to determine M {sub mol} {sub gas} with an accuracy of ±0.1 dex in relative terms, and ±0.2 dex including systematic uncertainties.« less

Authors:
; ; ; ;  [1];  [2];  [3];  [4];  [5]; ;  [6];  [7]; ; ;  [8]; ;  [9];  [10];  [11];  [12] more »; « less
  1. Max-Planck-Institut für Extraterrestrische Physik (MPE), Giessenbachstr., D-85748 Garching (Germany)
  2. Department of Physics and Astronomy, University College London, Gower Place, London WC1E 6BT (United Kingdom)
  3. Argelander-Institut für Astronomie, Universität Bonn, Auf dem Hügel 71, D-53121 Bonn (Germany)
  4. Observatoire de Paris, LERMA, CNRS, 61 Av. de l'Observatoire, F-75014 Paris (France)
  5. Observatorio Astronómico Nacional-OAN, Observatorio de Madrid, Alfonso XII, 3, 28014 Madrid (Spain)
  6. IRAM, 300 Rue de la Piscine, F-38406 St. Martin d'Heres, Grenoble (France)
  7. Department of Astronomy, University of Maryland, College Park, MD 20742-2421 (United States)
  8. Institut d'Astrophysique et de Planétologie, Universite de Toulouse, 9 Avenue du Colonel Roche BP 44346, F-31028 Toulouse Cedex 4 (France)
  9. Institute of Astronomy, Department of Physics, Eidgenössische Technische Hochschule, CH-8093 ETH Zürich (Switzerland)
  10. Service d'Astrophysique, DAPNIA, CEA/Saclay, F-91191 Gif-sur-Yvette Cedex (France)
  11. CSIC Instituto Estructura Materia, C/Serrano 121, E-28006 Madrid (Spain)
  12. Department of Physics and Astronomy, Frederick Reines Hall, University of California, Irvine, CA 92697 (United States)
Publication Date:
OSTI Identifier:
22364237
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 800; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CARBON MONOXIDE; GALAXIES; HYDROGEN; MAIN SEQUENCE STARS; MASS; PROBES; RED SHIFT; STAR EVOLUTION

Citation Formats

Genzel, R., Tacconi, L. J., Lutz, D., Berta, S., Burkert, A., Saintonge, A., Magnelli, B., Combes, F., García-Burillo, S., Neri, R., Boissier, J., Bolatto, A., Contini, T., Boone, F., Bouché, N., Lilly, S., Carollo, M., Bournaud, F., Colina, L., Cooper, M. C., E-mail: linda@mpe.mpg.de, E-mail: genzel@mpe.mpg.de, and and others. COMBINED CO AND DUST SCALING RELATIONS OF DEPLETION TIME AND MOLECULAR GAS FRACTIONS WITH COSMIC TIME, SPECIFIC STAR-FORMATION RATE, AND STELLAR MASS. United States: N. p., 2015. Web. doi:10.1088/0004-637X/800/1/20.
Genzel, R., Tacconi, L. J., Lutz, D., Berta, S., Burkert, A., Saintonge, A., Magnelli, B., Combes, F., García-Burillo, S., Neri, R., Boissier, J., Bolatto, A., Contini, T., Boone, F., Bouché, N., Lilly, S., Carollo, M., Bournaud, F., Colina, L., Cooper, M. C., E-mail: linda@mpe.mpg.de, E-mail: genzel@mpe.mpg.de, & and others. COMBINED CO AND DUST SCALING RELATIONS OF DEPLETION TIME AND MOLECULAR GAS FRACTIONS WITH COSMIC TIME, SPECIFIC STAR-FORMATION RATE, AND STELLAR MASS. United States. doi:10.1088/0004-637X/800/1/20.
Genzel, R., Tacconi, L. J., Lutz, D., Berta, S., Burkert, A., Saintonge, A., Magnelli, B., Combes, F., García-Burillo, S., Neri, R., Boissier, J., Bolatto, A., Contini, T., Boone, F., Bouché, N., Lilly, S., Carollo, M., Bournaud, F., Colina, L., Cooper, M. C., E-mail: linda@mpe.mpg.de, E-mail: genzel@mpe.mpg.de, and and others. Tue . "COMBINED CO AND DUST SCALING RELATIONS OF DEPLETION TIME AND MOLECULAR GAS FRACTIONS WITH COSMIC TIME, SPECIFIC STAR-FORMATION RATE, AND STELLAR MASS". United States. doi:10.1088/0004-637X/800/1/20.
@article{osti_22364237,
title = {COMBINED CO AND DUST SCALING RELATIONS OF DEPLETION TIME AND MOLECULAR GAS FRACTIONS WITH COSMIC TIME, SPECIFIC STAR-FORMATION RATE, AND STELLAR MASS},
author = {Genzel, R. and Tacconi, L. J. and Lutz, D. and Berta, S. and Burkert, A. and Saintonge, A. and Magnelli, B. and Combes, F. and García-Burillo, S. and Neri, R. and Boissier, J. and Bolatto, A. and Contini, T. and Boone, F. and Bouché, N. and Lilly, S. and Carollo, M. and Bournaud, F. and Colina, L. and Cooper, M. C., E-mail: linda@mpe.mpg.de, E-mail: genzel@mpe.mpg.de and and others},
abstractNote = {We combine molecular gas masses inferred from CO emission in 500 star-forming galaxies (SFGs) between z = 0 and 3, from the IRAM-COLDGASS, PHIBSS1/2, and other surveys, with gas masses derived from Herschel far-IR dust measurements in 512 galaxy stacks over the same stellar mass/redshift range. We constrain the scaling relations of molecular gas depletion timescale (t {sub depl}) and gas to stellar mass ratio (M {sub mol} {sub gas}/M{sub *} ) of SFGs near the star formation ''main-sequence'' with redshift, specific star-formation rate (sSFR), and stellar mass (M{sub *} ). The CO- and dust-based scaling relations agree remarkably well. This suggests that the CO → H{sub 2} mass conversion factor varies little within ±0.6 dex of the main sequence (sSFR(ms, z, M {sub *})), and less than 0.3 dex throughout this redshift range. This study builds on and strengthens the results of earlier work. We find that t {sub depl} scales as (1 + z){sup –0.3} × (sSFR/sSFR(ms, z, M {sub *})){sup –0.5}, with little dependence on M {sub *}. The resulting steep redshift dependence of M {sub mol} {sub gas}/M {sub *} ≈ (1 + z){sup 3} mirrors that of the sSFR and probably reflects the gas supply rate. The decreasing gas fractions at high M{sub *} are driven by the flattening of the SFR-M {sub *} relation. Throughout the probed redshift range a combination of an increasing gas fraction and a decreasing depletion timescale causes a larger sSFR at constant M {sub *}. As a result, galaxy integrated samples of the M {sub mol} {sub gas}-SFR rate relation exhibit a super-linear slope, which increases with the range of sSFR. With these new relations it is now possible to determine M {sub mol} {sub gas} with an accuracy of ±0.1 dex in relative terms, and ±0.2 dex including systematic uncertainties.},
doi = {10.1088/0004-637X/800/1/20},
journal = {Astrophysical Journal},
number = 1,
volume = 800,
place = {United States},
year = {Tue Feb 10 00:00:00 EST 2015},
month = {Tue Feb 10 00:00:00 EST 2015}
}