Deep CO(1-0) Observations of z=1.62 Cluster Galaxies with Substantial Molecular Gas Reservoirs and Normal Star Formation Efficiencies

Abstract

We present an extremely deep CO(1-0) observation of a confirmed $z=1.62$ galaxy cluster. We detect two spectroscopically confirmed cluster members in CO(1-0) with $S/N>5$. Both galaxies have log(${\mathcal{M}}_{\star }$/\msol)$>11$ and are gas rich, with ${\mathcal{M}}_{\mathrm{mol}}$/(${\mathcal{M}}_{\star }+{\mathcal{M}}_{\mathrm{mol}}$)$\sim 0.17-0.45$. One of these galaxies lies on the star formation rate (SFR)-${\mathcal{M}}_{\star }$ sequence while the other lies an order of magnitude below. We compare the cluster galaxies to other SFR-selected galaxies with CO measurements and find that they have CO luminosities consistent with expectations given their infrared luminosities. We also find that they have comparable gas fractions and star formation efficiencies (SFE) to what is expected from published field galaxy scaling relations. The galaxies are compact in their stellar light distribution, at the extreme end for all high redshift star-forming galaxies. However, their SFE is consistent with other field galaxies at comparable compactness. This is similar to two other sources selected in a blind CO survey of the HDF-N. Despite living in a highly quenched proto-cluster core, the molecular gas properties of these two galaxies, one of which may be in the processes of quenching, appear entirely consistent with field scaling relations between the molecular gas content, stellar mass, star formation rate, and redshift. We speculate that these cluster galaxies cannot have any further substantive gas accretion if they are to become members of the dominant passive population in $z<1$ clusters.

19 pages, 11 figures, 3 tables. Accepted for publication in the Astrophysical Journal

References in corpus (33)

• Star Formation in AEGIS Field Galaxies since z=1.1 : The Dominance of Gradually Declining Star Formation, and the Main Sequence of Star-Forming Galaxies
• EAZY: A Fast, Public Photometric Redshift Code
• Cold streams in early massive hot haloes as the main mode of galaxy formation
• A simple model to interpret the ultraviolet, optical and infrared emission from galaxies
• 3D-HST WFC3-selected Photometric Catalogs in the Five CANDELS/3D-HST Fields: Photometry, Photometric Redshifts and Stellar Masses
• Detection of quiescent galaxies in a bicolor sequence from z=0-2
• Combined CO & Dust Scaling Relations of Depletion Time and Molecular Gas Fractions with Cosmic Time, Specific Star Formation Rate and Stellar Mass
• Ubiquitous outflows in DEEP2 spectra of star-forming galaxies at z=1.4
• The KMOS^3D Survey: design, first results, and the evolution of galaxy kinematics from 0.7<z<2.7
• The Stellar, Gas and Dynamical Masses of Star-Forming Galaxies at z~2
• COLD GASS, an IRAM legacy survey of molecular gas in massive galaxies: I. Relations between H2, HI, stellar content and structural properties
• An ALMA survey of Sub-millimeter Galaxies in the Extended Chandra Deep Field South: Physical properties derived from ultraviolet-to-radio modelling
• The Galaxy Mass Function up to z=4 in the GOODS-MUSIC sample: into the epoch of formation of massive galaxies
• What do we learn from IRAC observations of galaxies at 2 < z < 3.5?
• The Discovery of 1000 km/s Outflows in Massive Post-starburst Galaxies at z=0.6
• Strangulation in Galaxy Groups
• CO excitation of normal star forming galaxies out to z=1.5 as regulated by the properties of their interstellar medium
• Kinemetry of SINS High-Redshift Star-Forming Galaxies: Distinguishing Rotating Disks from Major Mergers
• A Massive Molecular Gas Reservoir in the z=5.3 Submillimeter Galaxy AzTEC-3
• Spitzer Mid-to-Far-Infrared Flux Densities of Distant Galaxies
• Spectroscopic Confirmation Of An Extreme Starburst At Redshift 4.547
• Should we believe the results of UV-mm galaxy SED modelling?
• The Rest-Frame Optical Luminosity Function of Cluster Galaxies at z<0.8 and the Assembly of the Cluster Red Sequence
• The Angular Clustering of Distant Galaxy Clusters
• Measuring the Average Evolution of Luminous Galaxies at z<3: The Rest-frame Optical Luminosity Density, Spectral Energy Distribution, and Stellar Mass Density
• Overconsumption, outflows and the quenching of satellite galaxies
• Spitzer/MIPS 24um Observations of Galaxy Clusters: An Increasing Fraction of Obscured Star-forming Members from z=0.02 to z=0.83
• ALMA Observations of Gas-Rich Galaxies in z~1.6 Galaxy Clusters: Evidence for Higher Gas Fractions in High-Density Environments
• The environmental dependence of gas accretion onto galaxies: quenching satellites through starvation
• The reversal of the SF-density relation in a massive, X-ray selected galaxy cluster at z=1.58: results from Herschel
• Galaxy population properties of the massive X-ray luminous galaxy cluster XDCP J0044.0-2033 at z=1.58: red-sequence formation, massive galaxy assembly, and central star formation activity
• The Ages of Passive Galaxies in a z=1.62 Protocluster
• A blind CO detection of a Distant Red Galaxy in the HS1700+64 proto-cluster

Cited by in corpus (36)

• Ram Pressure Stripping in High-Density Environments
• Confirming Herschel candidate protoclusters from ALMA/VLA CO observations
• Quenching of star formation from a lack of inflowing gas to galaxies
• Environmental impacts on molecular gas in protocluster galaxies at z~2
• ALMA measures rapidly depleted molecular gas reservoirs in massive quiescent galaxies at z~1.5
• On the Gas Content, Star Formation Efficiency, and Environmental Quenching of Massive Galaxies in Proto-Clusters at z~2.0-2.5
• The Interstellar Medium of Quiescent Galaxies and its Evolution With Time
• COALAS: I. ATCA CO(1-0) survey and luminosity function in the Spiderweb protocluster at z=2.16
• Extremely Low Molecular Gas Content in a Compact, Quiescent Galaxy at z=1.522
• Molecular hydrogen in IllustrisTNG galaxies: carefully comparing signatures of environment with local CO & SFR data
• ALMA reveals large overdensity and strong clustering of galaxies in quasar environments at $z\sim 4$
• High-resolution ALMA study of CO (2-1) line and dust continuum emissions in cluster galaxies at z = 1.46
• Early Science with the Large Millimeter Telescope: Constraining the Gas Fraction of a Compact Quiescent Galaxy at z=1.883
• In pursuit of giants: II. Evolution of dusty quiescent galaxies over the last six billion years from the hCOSMOS survey
• The GOGREEN Survey: Constraining the Satellite Quenching Timescale in Massive Clusters at $\mathbf{z}\gtrsim 1$
• z-GAL -- A NOEMA spectroscopic redshift survey of bright Herschel galaxies: [III] Physical properties
• Resolved CO(1-0) emission and gas properties in luminous dusty star forming galaxies at z=2-4
• Significant Molecular Gas Deficiencies in Star-forming Cluster Galaxies at $z\sim 1.4$
• The large molecular gas fraction of post-starburst galaxies at z > 1
• Molecular gas properties of Planck-selected protocluster candidates at z~1.3-3
• The evolution of the gas fraction of quiescent galaxies modeled as a consequence of their creation rate
• The [CII] 158 $\mu$m emission line as a gas mass tracer in high redshift quiescent galaxies
• A large-scale kinematic study of molecular gas in high-z cluster galaxies: Evidence for high levels of kinematic asymmetry
• Star forming and gas rich brightest cluster galaxies at $z\sim 0.4$ in the Kilo-Degree Survey
• COALAS III: The ATCA CO(1-0) look at the growth and death of H$\alpha$ emitters in the Spiderweb protocluster at z=2.16
• The uncertain interstellar medium of high-redshift quiescent galaxies: Impact of methodology
• Accelerated structural evolution of galaxies in a starbursting cluster at z=2.51
• SEEDisCS II. Molecular gas in galaxy clusters and their large scale structure: low gas fraction galaxies, the case of CL1301.7$-$1139
• The relationship between cluster environment and molecular gas content of star-forming galaxies in the EAGLE simulation
• Molecular gas in a gravitationally lensed galaxy group at $z=2.9$
• Vz-GAL: Probing Cold Molecular Gas in Dusty Star-forming Galaxies at z=1-6
• An ALMA spectroscopic survey of the Planck high-redshift object PLCK G073.4-57.5 confirms two protoclusters
• ZFIRE -- The Gas Inflow Inequality for Satellite Galaxies in Cluster and Field Halos at z = 2
• ALMA measures molecular gas reservoirs comparable to field galaxies in a low-mass galaxy cluster at z=1.3
• Characterizing CO Emitters in the SSA22-AzTEC26 Field
• Fueling and feedback mechanisms at the nodes of the cosmic web