xCOLD GASS: The Complete IRAM 30 m Legacy Survey of Molecular Gas for Galaxy Evolution Studies

Saintonge, Amélie; Catinella, Barbara; Tacconi, Linda J.; Kauffmann, Guinevere; Genzel, Reinhard; Cortese, Luca; Davé, Romeel; Fletcher, Thomas J.; Graciá-Carpio, Javier; Kramer, Carsten; Heckman, Timothy M.; Janowiecki, Steven; Lutz, Katharina; Rosario, David; Schiminovich, David; Schuster, Karl; Wang, Jing; Wuyts, Stijn; Borthakur, Sanchayeeta; Lamperti, Isabella; Roberts-Borsani, Guido W.

doi:10.3847/1538-4365/aa97e0

xCOLD GASS: The Complete IRAM 30 m Legacy Survey of Molecular Gas for Galaxy Evolution Studies

Saintonge, Amélie; Catinella, Barbara; Tacconi, Linda J.; Kauffmann, Guinevere; Genzel, Reinhard; Cortese, Luca; Davé, Romeel; Fletcher, Thomas J.; Graciá-Carpio, Javier; Kramer, Carsten; Heckman, Timothy M.; Janowiecki, Steven; Lutz, Katharina; Rosario, David; Schiminovich, David; Schuster, Karl; Wang, Jing; Wuyts, Stijn; Borthakur, Sanchayeeta; Lamperti, Isabella; Roberts-Borsani, Guido W.

Authors

Amélie Saintonge

Barbara Catinella

Linda J. Tacconi

Guinevere Kauffmann

Reinhard Genzel

Luca Cortese

Romeel Davé

Thomas J. Fletcher

Javier Graciá-Carpio

Carsten Kramer

Timothy M. Heckman

Steven Janowiecki

Katharina Lutz

David Rosario

David Schiminovich

Karl Schuster

Jing Wang

Stijn Wuyts

Sanchayeeta Borthakur

Isabella Lamperti

Guido W. Roberts-Borsani

Abstract

We introduce xCOLD GASS, a legacy survey providing a census of molecular gas in the local universe. Building on the original COLD GASS survey, we present here the full sample of 532 galaxies with CO (1–0) measurements from the IRAM 30 m telescope. The sample is mass-selected in the redshift interval $0.01\lt z\lt 0.05$ from the Sloan Digital Sky Survey (SDSS) and therefore representative of the local galaxy population with ${M}_{* }\ \gt {10}^{9}\,{M}_{\odot }$. The CO (1–0) flux measurements are complemented by observations of the CO (2–1) line with both the IRAM 30 m and APEX telescopes, H i observations from Arecibo, and photometry from SDSS, WISE, and GALEX. Combining the IRAM and APEX data, we find that the ratio of CO (2–1) to CO (1–0) luminosity for integrated measurements is ${r}_{21}=0.79\pm 0.03$, with no systematic variations across the sample. The CO (1–0) luminosity function is constructed and best fit with a Schechter function with parameters ${L}_{\mathrm{CO}}^{* }=(7.77\pm 2.11)\times {10}^{9}\,{\rm{K}}\,\mathrm{km}\,{{\rm{s}}}^{-1}\,{\mathrm{pc}}^{2}$, ${\phi }^{* }=(9.84\pm 5.41)\times {10}^{-4}\,{\mathrm{Mpc}}^{-3}$, and $\alpha =-1.19\pm 0.05$. With the sample now complete down to stellar masses of 109 ${M}_{\odot }$, we are able to extend our study of gas scaling relations and confirm that both molecular gas fractions (${f}_{{{\rm{H}}}_{2}}$) and depletion timescale (${t}_{\mathrm{dep}}({{\rm{H}}}_{2})$) vary with specific star formation rate (or offset from the star formation main sequence) much more strongly than they depend on stellar mass. Comparing the xCOLD GASS results with outputs from hydrodynamic and semianalytic models, we highlight the constraining power of cold gas scaling relations on models of galaxy formation.

Citation

Saintonge, A., Catinella, B., Tacconi, L. J., Kauffmann, G., Genzel, R., Cortese, L., …Roberts-Borsani, G. W. (2017). xCOLD GASS: The Complete IRAM 30 m Legacy Survey of Molecular Gas for Galaxy Evolution Studies. Astrophysical Journal Supplement, 233(2), Article 22. https://doi.org/10.3847/1538-4365/aa97e0

Journal Article Type	Article
Acceptance Date	Oct 2, 2017
Online Publication Date	Dec 8, 2017
Publication Date	Dec 8, 2017
Deposit Date	Jan 5, 2018
Publicly Available Date	Jan 5, 2018
Journal	Astrophysical Journal Supplement
Print ISSN	0067-0049
Electronic ISSN	1538-4365
Publisher	American Astronomical Society
Peer Reviewed	Peer Reviewed
Volume	233
Issue	2
Article Number	22
DOI	https://doi.org/10.3847/1538-4365/aa97e0