J/ApJ/874/54ivo://CDS.VizieR/J/ApJ/874/54doi:10.26093/cds/vizier.18740054CDSMacuga M.Martini P.Miller E.D.Brodwin M.Hayashi M.Kodama T.,Koyama Y.Overzier R.A.Shimakawa R.Tadaki K.-I.Tanaka I.2021-03-23T12:33:03Z2020-09-14T10:55:32ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frx-ray-sourcesgalaxy-clustersactive-galactic-nucleiThe incidence of active galactic nuclei (AGNs) within the local environment is a potentially valuable probe of the mechanisms that trigger and provide fuel for accretion onto supermassive black holes. While the correlation between AGN fraction and environment has been well-studied in the local universe, AGN fractions have been measured for relatively few dense environments at high redshift. In this paper, we present a measurement of the X-ray AGN fraction in the USS 1558-003 protocluster associated with the z=2.53 radio galaxy 4C-00.62. Our measurement is based on a 100-ks Chandra observation, follow-up spectroscopy from the Multi-Object Double Spectrograph on the Large Binocular Telescope, and broad and narrowband photometry. These data are sensitive to AGNs more luminous than L_X_>2x10^43^erg/s in the rest-frame hard X-ray band (2-10keV). We have identified two X-ray AGNs at the redshift of USS 1558-003, one of which is the radio galaxy. We have determined that 2.0_-1.3_^+2.6^% of the H{alpha} emitters in the protocluster are X-ray AGNs. Unlike most other high-redshift cluster progenitors studied with similar techniques, USS1558-003 does not have a significantly higher fraction of AGNs than field galaxies at similar redshifts. This lower AGN fraction is inconsistent with the expectation that the higher gas fractions at high redshift, combined with the high galaxy densities and modest relative velocities in protoclusters, should produce higher AGN fractions.2019ApJ...874...54Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/874/54CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/chandra : The Chandra Archive Log (CXC, 1999-2014)J/ApJ/592/728 : Lyman break galaxies at redshift z~3 (Steidel+, 2003)J/ApJS/184/158 : Chandra COSMOS survey I. (Elvis+, 2009)J/ApJ/701/587 : Deep HST H-band survey. II. QUEST QSOs (Veilleux+, 2009)J/ApJ/761/114 : Multi-wavelength study of clusters of gal. II. (Atlee+, 2012)J/ApJ/765/87 : Chandra obs. of the 2QZ Cluster 1004+00 (Lehmer+, 2013)J/MNRAS/428/1128 : UDS/COSMOS HiZELS galaxies (Sobral+, 2013)J/ApJ/825/72 : Follow-up study of AGNs in z>1 clusters (Alberts+, 2016)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/874/54https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/874/54http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/874/54https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/874/54https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/874/54http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/874/54GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/874/54/table1 (X-ray sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/874/54/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/874/54/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/874/54/table1?GETtext/xml+votable180.050000true240.322-0.4790.0055555555555555566/31332https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/874/54?format=asciiX-raydefaultJ/ApJ/874/54/table1X-ray sourcesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000[240.14/240.46] Right Ascension (J2000)degpos.eq.ra;meta.mainDEJ2000[-0.76/-0.31] Declination (J2000)degpos.eq.dec;meta.mainNetCts[6.991/617.102] Net photon countsctphot.count;em.X-rayfloatFlux[8.8e-16/8.4e-14] X-ray flux in 0.5-7keV bandmW.m**-2phot.flux;em.X-raydoublee_Flux[3.4e-16/4.3e-15] Error in FluxmW.m**-2stat.error;phot.fluxdoubleMm[yn] Confirmation as cluster member ("y" = 2 occurrences)meta.code.memberchar