Spectroscopic Confirmation of a Coma Cluster Progenitor at z ~ 2.2

Abstract

We report the spectroscopic confirmation of a new protocluster in the COSMOS field at $z$ $\sim$ 2.2, COSMOS Cluster 2.2 (CC2.2), originally identified as an overdensity of narrowband selected H$\alpha$ emitting candidates. With only two masks of Keck/MOSFIRE near-IR spectroscopy in both $H$ ($\sim$ 1.47-1.81 $\mu$m) and $K$ ($\sim$ 1.92-2.40 $\mu$m) bands ($\sim$ 1.5 hour each), we confirm 35 unique protocluster members with at least two emission lines detected with S/N $>$ 3. Combined with 12 extra members from the zCOSMOS-deep spectroscopic survey (47 in total), we estimate a mean redshift and a line-of-sight velocity dispersion of $z_{mean}$=2.23224 $\pm$ 0.00101 and ${\sigma }_{los}$=645 $\pm$ 69 km s${}^{-1}$ for this protocluster, respectively. Assuming virialization and spherical symmetry for the system, we estimate a total mass of $M_{vir}$ $\sim$ $(1-2)\times$10${}^{14}$ $M_{\odot }$ for the structure. We evaluate a number density enhancement of ${\delta }_g$ $\sim$ 7 for this system and we argue that the structure is likely not fully virialized at $z$ $\sim$ 2.2. However, in a spherical collapse model, ${\delta }_g$ is expected to grow to a linear matter enhancement of $\sim$ 1.9 by $z$=0, exceeding the collapse threshold of 1.69, and leading to a fully collapsed and virialized Coma-type structure with a total mass of $M_{dyn}$($z$=0) $\sim$ 9.2$\times$10${}^{14}$ $M_{\odot }$ by now. This observationally efficient confirmation suggests that large narrowband emission-line galaxy surveys, when combined with ancillary photometric data, can be used to effectively trace the large-scale structure and protoclusters at a time when they are mostly dominated by star-forming galaxies.

References in corpus (66)

• A Universal Density Profile from Hierarchical Clustering
• Cosmic Star Formation History
• The Cosmic Evolution Survey (COSMOS) -- Overview
• An analytic model for the spatial clustering of dark matter haloes
• COSMOS Photometric Redshifts with 30-bands for 2-deg2
• The COSMOS2015 Catalog: Exploring the 1<z<6 Universe with half a million galaxies
• Mass assembly in quiescent and star-forming galaxies since z=4 from UltraVISTA
• UltraVISTA: a new ultra-deep near-infrared survey in COSMOS
• A Large Structure of Galaxies At Redshift z~3 and its Cosmological Implications
• The Chandra COSMOS Legacy survey: overview and point source catalog
• The Chandra COSMOS Survey, I: Overview and Point Source Catalog
• A large Hα survey at z=2.23, 1.47, 0.84 & 0.40: the 11 Gyr evolution of star-forming galaxies from HiZELS
• Ancient Light from Young Cosmic Cities: Physical and Observational Signatures of Galaxy Proto-Clusters
• The Chandra COSMOS Legacy survey: optical/IR identifications
• The realm of the galaxy protoclusters
• A Subaru Search for Ly-alpha Blobs in and around the Proto-cluster Region at Redshift z=3.1
• A massive proto-cluster of galaxies at a redshift of z {\approx} 5.3
• A Spitzer-Selected Galaxy Cluster at z=1.62
• The Average Mass Profile of Galaxy Clusters
• The relation between velocity dispersion and mass in simulated clusters of galaxies: dependence on the tracer and the baryonic physics
• Halo mass function: Baryon impact, fitting formulae and implications for cluster cosmology
• Discovery of a galaxy cluster with a violently starbursting core at z=2.506
• Galaxy Clusters around radio-loud AGN at 1.3 < z < 3.2 as seen by Spitzer
• The VLA-COSMOS Survey. IV. Deep Data and Joint Catalog
• The most distant structure of galaxies known: a protocluster at z=4.1
• An extreme proto-cluster of luminous dusty starbursts in the early Universe
• Spectroscopic Identification of a Proto-Cluster at z=2.300: Environmental Dependence of Galaxy Properties at High Redshift
• Effects of Local Environment and Stellar Mass on Galaxy Quenching out to z~3
• The stellar mass function of star-forming galaxies and the mass-dependent SFR function since z=2.23 from HiZELS
• Cosmological structure formation in a homogeneous dark energy background
• A Comparative Study of Density Field Estimation for Galaxies: New Insights into the Evolution of Galaxies with Environment in COSMOS out to z~3
• The progeny of a Cosmic Titan: a massive multi-component proto-supercluster in formation at z=2.45 in VUDS
• Discovery of a Rich Cluster at z = 1.63 using the Rest-Frame 1.6um "Stellar Bump Sequence" Method
• Massive starburst galaxies in a z=2.16 proto-cluster unveiled by panoramic H-alpha mapping
• Evolution of the H$\beta$+[OIII] and [OII] luminosity functions and the [OII] star-formation history of the Universe up to $z$ ~ 5 from HiZELS
• Cosmic Web of Galaxies in the COSMOS Field: Public Catalog and Different Quenching for Centrals and Satellites
• The CALYMHA survey: Lya luminosity function and global escape fraction of Lya photons at z=2.23
• Discovery of a rich proto-cluster at z=2.9 and associated diffuse cold gas in the VIMOS Ultra-Deep Survey (VUDS)
• The VIMOS Ultra Deep Survey: Emerging from the Dark, a Massive Proto-Cluster at z~4.57
• The clustering of H-alpha emitters at z=2.23 from HiZELS
• The CALYMHA survey: Ly$\alpha$ escape fraction and its dependence on galaxy properties at $z=2.23$
• HerMES: Clusters of Dusty Galaxies Uncovered by Herschel and Planck
• ALMA Observations of Gas-Rich Galaxies in z~1.6 Galaxy Clusters: Evidence for Higher Gas Fractions in High-Density Environments
• Surveying Galaxy Proto-clusters in Emission: A Large-scale Structure at z=2.44 and the Outlook for HETDEX
• MAHALO Deep Cluster Survey I. Accelerated and enhanced galaxy formation in the densest regions of a protocluster at z=2.5
• Molecular gas reservoirs in cluster galaxies at z=1.46
• KECK/MOSFIRE spectroscopic confirmation of a Virgo-like cluster ancestor at z=2.095
• VIMOS Ultra-Deep Survey (VUDS): Witnessing the Assembly of a Massive Cluster at z~3.3
• An early phase of environmental effects on galaxy properties unveiled by near-infrared spectroscopy of protocluster galaxies at z>2
• The Absence of an Environmental Dependence in the Mass-Metallicity Relation at z=2
• Metal deficiency in cluster star-forming galaxies at z=2
• A proto-cluster at z=2.45
• Revealing environmental dependence of molecular gas content in a distant X-ray cluster at z=2.51
• Large Scale Structures in the CANDELS Fields: The Role of the Environment in Star Formation Activity
• Discovery of a Very Large Structure at Z=3.78
• Environmental impacts on molecular gas in protocluster galaxies at z~2
• Concurrent Supermassive Black Hole and Galaxy Growth: Linking Environment and Nuclear Activity in z = 2.23 H-alpha Emitters
• Boötes-HiZELS: an optical to near-infrared survey of emission-line galaxies at $\mathbf{z}=0.4-4.7$
• A radio-to-mm census of star-forming galaxies in protocluster 4C23.56 at z=2.5 : Gas mass and its fraction revealed with ALMA
• Discovery of a Proto-cluster Associated with a Ly-$\alpha$ Blob Pair at z=2.3
• An H-alpha search for over-dense regions at z=2.23
• Similar Scaling Relations for the Gas Content of Galaxies across Environments to z ~ 3.5
• Candidate Clusters of Galaxies at $z>1.3$ Identified in the Spitzer SPT Deep Field Survey
• Passive galaxies as tracers of cluster environments at z~2
• The growth of typical star-forming galaxies and their super massive black holes across cosmic time since z~2
• Mass-Richness relations for X-ray and SZE-selected clusters at $0.4<z<2.0$ as seen by $Spitzer$ at 4.5$\mu$m

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• Large Scale Structures in COSMOS2020: Evolution of Star Formation Activity in Different Environments at 0.4 < z < 4
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• Observational Evidence for Large-Scale Gas Heating in a Galaxy Protocluster at z=2.30
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• ENISALA: II. Distinct Star Formation and Active Galactic Nucleus Activity in Merging and Relaxed Galaxy Clusters
• Evidence for gas-phase metal deficiency in massive protocluster galaxies at z~2.2
• Discovering Large-Scale Structure at $2<z<5$ in the C3VO Survey
• Environmental impacts on the rest-frame UV size and morphology ofstar-forming galaxies at $z\sim 2$
• The COSMOS-Web deep galaxy group catalog up to $z=3.7$
• Insights into environmental quenching at $z\sim 1$: an enhancement of faint, low-mass passive galaxies in clusters
• LATIS: A Sample of IGM-selected Protoclusters and Protogroups at $z\sim 2.5$
• Spectroscopic confirmation of the galaxy clusters CARLA J0950+2743 at z=2.363, and CARLA-Ser J0950+2743 at z=2.243
• The HST-Hyperion Survey: Companion Fraction and Overdensity in a z ~ 2.5 Proto-supercluster
• Probing the influence of the protocluster environment on galaxy morphology at z = 2.23
• Fueling and feedback mechanisms at the nodes of the cosmic web