The 700 ks Chandra Spiderweb Field I: evidence for widespread nuclear activity in the Protocluster

Abstract

(Abridged) We present an analysis of the 700 ks Chandra ACIS-S observation of the field around the Spiderweb Galaxy at z=2.156, focusing on the nuclear activity in the associated large-scale environment. We identify unresolved X-ray sources down to flux limits of 1.3X10^{-16} and 3.9X10^{-16} erg/s/cm^2 in the soft and hard band, respectively. We search for counterparts in the optical, NIR and submm bands to identify X-ray sources belonging to the protocluster. We detect 107 X-ray unresolved sources within 5 arcmin (corresponding to 2.5 Mpc) of J1140-2629, among which 13 have optical counterparts with spectroscopic redshift 2.11<z<2.20, and 1 source with photometric redshift consistent with this range. Our X-ray spectral analysis shows that their intrinsic spectral slope is consistent with an average <Γ>~1.84+-0.04. The best-fit intrinsic absorption for 5 protocluster X-ray members is N_H>10^{23} cm^{-2}, while other 6 have upper limits of the order of fewX10^{22} cm^{-2}. Two sources can only be fitted with very flat Γ<=1, and are therefore considered Compton-thick candidates. Their 0.5-10 keV rest frame luminosities are larger than 2X10^{43} erg/s, significantly greater than X-ray luminosities expected from star formation activity. The X-ray luminosity function of AGN in the volume associated to the Spiderweb protocluster in the range 10^{43}<L_X<10^{44.5} erg/s, is at least 10 times higher than that in the field at the same redshift and significantly flatter. The X-ray AGN fraction is measured to be (25.5+-4.5)% in the stellar mass range log(M*/M_sun)>10.5, corresponding to an enhancement of 6.0^{+9.0}_{-3.0} with respect to the COSMOS field at comparable redshifts and stellar mass range. We conclude that the galaxy population in the Spiderweb Protocluster is characterized by enhanced X-ray nuclear activity triggered by environmental effects on Mpc scales.

Astronomy & Astrophysics. Minor changes in this version. Version accepted in A&A

References in corpus (36)

• EAZY: A Fast, Public Photometric Redshift Code
• HI4PI: A full-sky HI survey based on EBHIS and GASS
• An ultra-deep near-infrared spectrum of a compact quiescent galaxy at z=2.2
• The synthesis of the cosmic X-ray background in the Chandra and XMM-Newton era
• The Chandra Deep Field-South Survey: 7 Ms Source Catalogs
• X-ray spectral properties of AGN in the Chandra Deep Field South
• The Massive Hosts of Radio Galaxies Across Cosmic Time
• GOODS-HERSCHEL: star formation, dust attenuation and the FIR-radio correlation on the Main Sequence of star-forming galaxies up to z~4
• The First Appearance of the Red Sequence of Galaxies in Proto-Clusters at 2<~z<~3
• Deep U band and R imaging of GOODS-South: Observations,data reduction and first results
• An excess of dusty starbursts related to the Spiderweb galaxy
• Ram pressure feeding super-massive black holes
• The Spiderweb galaxy: a forming massive cluster galaxy at z~2
• Spectroscopic Confirmation of a Large AGN Population in Clusters of Galaxies
• Identification of the progenitors of rich clusters and member galaxies in rapid formation at z>2
• The reversal of the SF-density relation in a massive, X-ray selected galaxy cluster at z=1.58: results from Herschel
• The Nascent Red Sequence at z~2
• Environmental impacts on molecular gas in protocluster galaxies at z~2
• Enhancement of AGN in a protocluster at z=1.6
• Mock catalogs for the extragalactic X-ray sky: simulating AGN surveys with Athena and with the AXIS probe
• The growth and assembly of a massive galaxy at z ~ 2
• The properties of the AGN torus as revealed from a set of unbiased NuSTAR observations
• COALAS: I. ATCA CO(1-0) survey and luminosity function in the Spiderweb protocluster at z=2.16
• Spectroscopic observations of PHz G237.01+42.50: A galaxy protocluster at z=2.16 in the Cosmos field
• Compton-thick AGN in the NuSTAR era III: A systematic study of the torus covering factor
• Comprehensive Gas Characterization of a $z=2.5$ Protocluster: A Cluster Core Caught in the Beginning of Virialization?
• X-ray bright active galactic nuclei in massive galaxy clusters III: New insights into the triggering mechanisms of cluster AGN
• Chandra Observations of the Cl1604 Supercluster at z=0.9: Evidence for an Overdensity of Active Galactic Nuclei
• Lyman-Alpha Emitter Galaxies at z ~ 2.8 in the Extended Chandra Deep Field-South: I. Tracing the Large-Scale Structure via Lyman-Alpha Imaging
• High density of active galactic nuclei in the outskirts of distant galaxy clusters
• Chandra reveals a luminous Compton-thick QSO powering a $Ly\alpha$ blob in a $z=4$ starbursting protocluster
• Chandra point-source counts in distant galaxy clusters
• On the Nature of AGN and Star Formation Enhancement in the $z=3.1$ SSA22 Protocluster: The HST WFC3 IR View
• The XMM deep survey in the CDFS XI. X-ray properties of 185 bright sources
• Triggering nuclear and galaxy activity in the Bullet cluster
• Feedback Factory: Multiple faint radio-jets detected in a cluster at z=2

Cited by in corpus (28)

• Forming intracluster gas in a galaxy protocluster at a redshift of 2.16
• Signs of environmental effects on star-forming galaxies in the Spiderweb protocluster at z=2.16
• Cosmic Vine: A z=3.44 large-scale structure hosting massive quiescent galaxies
• The 700 ks Chandra Spiderweb Field II: Evidence for inverse-Compton and thermal diffuse emission in the Spiderweb galaxy
• Evaluating Lya Emission as a Tracer of the Largest Cosmic Structure at z~2.47
• The Spiderweb proto-cluster is being magnetized by its central radio jet
• Magnetic fields catalyze massive black hole formation and growth
• Fast SMBH growth in the SPT2349--56 protocluster at $z=4.3$
• Revisiting the Properties of X-ray AGN in the SSA22 Protocluster: Normal SMBH and Host-Galaxy Growth for AGN in a $z=3.09$ Overdensity
• Feeding and feedback processes in the Spiderweb proto-intracluster medium
• Environmental impacts on the rest-frame UV size and morphology ofstar-forming galaxies at $z\sim 2$
• ASW${}^2$DF: Census of the obscured star formation in a galaxy cluster in formation at $z=2.2$
• The cooler past of the intracluster medium in TNG-Cluster
• Revealing the quiescent galaxy population in the Spiderweb protocluster at z=2.16 with deep HST/WFC3 slitless spectroscopy
• 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
• VLBI Imaging of high-redshift galaxies and protoclusters at low radio frequencies with the International LOFAR Telescope
• JWST/NIRCam Narrowband Survey of Pa$\beta$ Emitters in the Spiderweb Protocluster at z=2.16
• Connecting the growth of galaxies to the large-scale environment in a massive node of the Cosmic Web at z~3
• Galaxy populations of ProtoClusters in cosmological hydrodynamical simulations
• AGN feedback in an infant galaxy cluster: the LOFAR-Chandra view of the giant FRII radio galaxy J103025+052430 at z=1.7
• Enhanced strong-lensing model of MACS~J0138.0$-$2155 based on new JWST and VLT/MUSE observations
• Quantifying the Impact of Incompleteness on Identifying and Interpreting Galaxy Protocluster Populations with the TNG-Cluster Simulation
• LBT-MODS spectroscopy of high-redshift candidates in the Chandra J1030 field. A newly discovered z$\sim$2.8 large scale structure
• JWST reveals extended stellar disks for ALMA-bright dusty star-forming galaxies in the Spiderweb protocluster
• ADF22+: a declining faint end in the far-infrared luminosity function in the SSA22 protocluster at z=3.09
• Enhanced AGN Activity in Overdense Galactic Environments at $2<z<4$
• Spectroscopic confirmation of the galaxy clusters CARLA J0950+2743 at z=2.363, and CARLA-Ser J0950+2743 at z=2.243
• Fueling and feedback mechanisms at the nodes of the cosmic web