J/MNRAS/440/2810ivo://CDS.VizieR/J/MNRAS/440/2810doi:10.26093/cds/vizier.74402810CDSBowler R.A.A.Dunlop J.S.McLure R.J.Rogers A.B.McCracken H.J.,Milvang-Jensen B.Furusawa H.Fynbo J.P.U.Taniguchi Y.Afonso J.,Bremer M.N.Le Fevre O.2024-08-08T20:13:14Z2015-04-23T08:48:28ZCDS support team

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

cds-question@unistra.frgalaxiesphotometryredshiftedWe present the results of a new search for bright star-forming galaxies at redshift z=~7 within the UltraVISTA second data release (DR2) and UKIDSS (UKIRT Infrared Deep Sky Survey) UDS (Ultra Deep Survey) DR10 data, which together provide 1.65deg^2^ of near-infrared imaging with overlapping optical and Spitzer data. Using a full photometric redshift analysis, to identify high-redshift galaxies and reject contaminants, we have selected a sample of 34 luminous (-22.7<M_UV_<-21.2) galaxies with 6.5<z<7.5. Crucially, the deeper imaging provided by UltraVISTA DR2 confirms all of the robust objects previously uncovered by Bowler et al., validating our selection technique. Our new expanded galaxy sample includes the most massive galaxies known at z=~7, with M*=~10^10^M_{sun}_, and the majority are resolved, consistent with larger sizes (r_1/2_=~1-1.5kpc) than displayed by less massive galaxies. From our final robust sample, we determine the form of the bright end of the rest-frame UV galaxy luminosity function (LF) at z=~7, providing strong evidence that it does not decline as steeply as predicted by the Schechter-function fit to fainter data. We exclude the possibility that this is due to either gravitational lensing, or significant contamination of our galaxy sample by active galactic nuclei (AGN). Rather, our results favour a double power-law form for the galaxy LF at high redshift, or, more interestingly, an LF which simply follows the form of the dark matter halo mass function at bright magnitudes. This suggests that the physical mechanism which inhibits star formation activity in massive galaxies (i.e. AGN feedback or some other form of 'mass quenching') has yet to impact on the observable galaxy LF at z=~7, a conclusion supported by the estimated masses of our brightest galaxies which have only just reached a mass comparable to the critical 'quenching mass' of M*=~10^10.2^M_{sun}_ derived from studies of the mass function of star-forming galaxies at lower redshift.2014MNRAS.440.2810Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/440/2810CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/440/2810https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/440/2810http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/440/2810https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/440/2810https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/440/2810http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/440/2810GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/440/2810/sample (Photometry (table2), model parameters (table3) and physiscal properties (table4) of our final UltraVista ans UDS samples)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/440/2810/sample?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/440/2810/sample?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/440/2810/sample?GETtext/xml+votable180.050000true149.81620832.12555560.0055555555555555566/17688 17690 27247 27256 27258-272593.9193497546148093e-20 6.185923063528282e-20https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/440/2810?format=asciiOpticaldefaultJ/MNRAS/440/2810/samplePhotometry (table2), model parameters (table3) and physiscal properties (table4) of our final UltraVista ans UDS samplesM1500[-23/-21.2] Absolute magnitude (8)magphys.magAbsfloatl_JmagLimit flag on Jmagmeta.code.errorcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID[2103/583226] ID numbermeta.id;meta.mainintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainl_z'magLimit flag on z'magmeta.code.errorcharz'magUKIRT z' magnitude (1)magphot.mag;em.opt.IfloatE_z'mag? Error on z'mag (upper value)magstat.error;stat.maxfloatnullablee_z'mag? Error on z'mag (lower value)magstat.error;phot.mag;em.opt.Ifloatnullablel_NB921Limit flag on l_NB921meta.code.errorcharNB921? UKIRT NB921 magnitude (1)magphot.mag;em.opt.IfloatnullableE_NB921? Error on NB921 (upper value)magstat.error;stat.maxfloatnullablee_NB921? Error on NB921 (lower value)magstat.errorfloatnullableYmagUKIRT Y magnitude (1)magphot.mag;em.IR.JfloatE_YmagError on Ymag (upper value)magstat.error;stat.maxfloate_YmagError on Ymag (lower value)magstat.error;phot.mag;em.opt.BfloatJmag? UKIRT J magnitude (1)magphot.mag;em.IR.JfloatnullableE_Jmag? Error on Jmag (upper value)magstat.error;stat.maxfloatnullablee_Jmag? Error on Jmag (lower value)magstat.error;phot.mag;em.IR.Jfloatnullablel_HmagLimit flag on Hmagmeta.code.errorcharHmag? UKIRT H magnitude (1)magphot.mag;em.IR.HfloatnullableE_Hmag? Error on Hmag (upper value)magstat.error;stat.maxfloatnullablee_Hmag? Error on Hmag (lower value)magstat.error;phot.mag;em.IR.Hfloatnullablel_KmagLimit flag on Kmagmeta.code.errorcharKmag? UKIRT K magnitude (1)magphot.mag;em.IR.KfloatnullableE_Kmag? Error on Kmag (upper value)magstat.error;stat.maxfloatnullablee_Kmag? Error on Kmag (lower value)magstat.error;phot.mag;em.IR.Kfloatnullablel_[3.6]Limit flag on [3.6]meta.code.errorchar[3.6]? Spitzer/IRAC 3.6um magnitude (1)magphot.mag;em.IR.3-4umfloatnullableE_[3.6]? Error on [3.6] (upper value)magstat.error;stat.maxfloatnullablee_[3.6]? Error on [3.6] (lower value)magstat.errorfloatnullablel_[4.5]Limit flag on [4.5]meta.code.errorchar[4.5]? Spitzer/IRAC 4.5um magnitude (1)magphot.mag;em.IR.4-8umfloatnullableE_[4.5]? Error on [4.5] (upper value)magstat.error;stat.maxfloatnullablee_[4.5]? Error on [4.5] (lower value)magstat.errorfloatnullableB12Bowler et al. (2012MNRAS.426.2772B) galaxy number or H for 'Himiko' galaxy from Ouchi et al. (2013ApJ...778..102O)meta.idcharfc[+] + indicates that the [3.6] and [4.5] photometry is confusedmeta.codecharz[6.0/7.3] Best-fitting photometric redshiftsrc.redshift.photfloatE_zError on z (upper value)stat.error;stat.maxfloate_zError on z (lower value)stat.error;src.redshiftfloatchi2N{chi}^2^ value for "No Ly{alpha}" case (2)stat.fit.chi2floatf_chi2N[+] Confused IRAC photometry (3)meta.codecharAVNAbsorption in V band for "No Ly{alpha}" case (2)magphys.absorptionfloatZN[0.2/1] Z abundance for "No Ly{alpha}" case (2)log(Sun)src.redshiftfloatzN[6.3/7.7] Redshift for "No Ly{alpha}" case (2)src.redshift.photfloatchi2W{chi}^2^ value for "With Ly{alpha}" case (2)stat.fit.chi2floatEW0Rest-frame Ly{alpha} equivalent width for "With Ly{alpha}" case (2)0.1nmspect.line.eqWidthintAVW[0/1] Absorption in V band for "With Ly{alpha}" case (2)magphys.absorptionfloatZW[0.2/1] Z abundance for "With Ly{alpha}" case (2)log(Sun)src.redshiftfloatSpTBest-fitting stellar templatesrc.spTypecharchi2{chi}^2^ value of best-fitting stellar templatestat.fit.chi2floatFWHMz'[0/9]? FWHM for z' band (4)arcsecphys.angSizefloatnullableFWHMY[0/9]? FWHM for Y band (4)arcsecphys.angSizefloatnullableFWHMJ[0/9]? FWHM for J band (4)arcsecphys.angSizefloatnullablelogM*Stellar mass (6)log(solMass.yr**-1)phys.massfloatE_logM*Error on logM (upper value)log(solMass.yr**-1)stat.error;stat.maxfloate_logM*Error on logM (lower value)log(solMass.yr**-1)stat.errorfloatSFR[3/250] Star formation rate (6)solMass/yrphys.SFRintE_SFRError on SFR (upper value)solMass/yrstat.error;stat.maxinte_SFRError on SFR (lower value)solMass/yrstat.error;phys.SFRintsSFR[0.2/100] Specific star-formation rate (6)Gyr**-1phys.SFRfloatE_sSFRError on SFRs (upper value)Gyr**-1stat.error;stat.maxfloate_sSFRError on SFRs (lower value)Gyr**-1stat.errorfloatSFRUV[9/47] Star formation rate from rest-frame UV flux (7)solMass/yrphys.SFRintbYJHK[-4.1/-1.5]? Rest-frame UV slope index {beta} calculated by fitting a power law to the measured YJHK photometry (9)spect.indexfloatnullablee_bYJHK? rms uncertainty on bYJHKstat.errorfloatnullablebJHK[-3.9/-0.8]? Rest-frame UV slope index {beta} calculated by fitting a power law to the measured JHK photometry (9)spect.indexfloatnullablee_bJHK? rms uncertainty on bJHKstat.errorfloatnullableJ/MNRAS/440/2810/galaxiesDR2 UltraVISTA magnitudes and best-fitting parameters for the 10 galaxy candidates presented in Bowler et al. (2012MNRAS.426.2772B)e_zError on z (lower value)stat.error;src.redshiftfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID[2103/583226] ID numbermeta.id;meta.mainintl_z'magLimit flag on z'magmeta.code.errorcharz'magUKIRT z' magnitude (1)magphot.mag;em.opt.IfloatE_z'mag? Error on z'mag (upper value)magstat.error;stat.maxfloatnullablee_z'mag? Error on z'mag (lower value)magstat.error;phot.mag;em.opt.IfloatnullableS/Nz'[0/16] Signal-to-noise of the z' detectionstat.snrintYmagUKIRT Y magnitude (1)magphot.mag;em.IR.JfloatE_YmagError on Ymag (upper value)magstat.error;stat.maxfloate_YmagError on Ymag (lower value)magstat.error;phot.mag;em.opt.BfloatS/NY[3/16] Signal-to-noise of the Y detectionstat.snrintJmagUKIRT J magnitude (1)magphot.mag;em.IR.JfloatE_JmagError on Jmag (upper value)magstat.error;stat.maxfloate_JmagError on Jmag (lower value)magstat.error;phot.mag;em.IR.JfloatS/NJ[2/12] Signal-to-noise of the J detectionstat.snrintl_HmagLimit flag on Hmagmeta.code.errorcharHmagUKIRT H magnitude (1)magphot.mag;em.IR.HfloatE_Hmag? Error on Hmag (upper value)magstat.error;stat.maxfloatnullablee_Hmag? Error on Hmag (lower value)magstat.error;phot.mag;em.IR.HfloatnullableS/NH[0/11] Signal-to-noise of the H detectionstat.snrintl_KsmagLimit flag on Ksmagmeta.code.errorcharKsmagUKIRT Ks magnitude (1)magphot.mag;em.IR.KfloatE_Ksmag? Error on Ksmag (upper value)magstat.error;stat.maxfloatnullablee_Ksmag? Error on Ksmag (lower value)magstat.error;phot.mag;em.IR.KfloatnullableS/NKs[0/13] Signal-to-noise of the Ks detectionstat.snrintl_[3.6]Limit flag on [3.6]meta.code.errorchar[3.6]Spitzer/IRAC 3.6um magnitude (1)magphot.mag;em.IR.3-4umfloatE_[3.6]? Error on [3.6] (upper value)magstat.error;stat.maxfloatnullablee_[3.6]? Error on [3.6] (lower value)magstat.errorfloatnullableS/N3.6[0/5] Signal-to-noise of the 3.6um detectionstat.snrintl_[4.5]Limit flag on [4.5]meta.code.errorchar[4.5]Spitzer/IRAC 4.5um magnitude (1)magphot.mag;em.IR.4-8umfloatE_[4.5]? Error on [4.5] (upper value)magstat.error;stat.maxfloatnullablee_[4.5]? Error on [4.5] (lower value)magstat.errorfloatnullableS/N4.5[0/5] Signal-to-noise of the 4.5um detectionstat.snrintSimbadSimbad column added by the CDSmeta.ref.urlcharz[6.0/7.3] Best-fitting photometric redshiftsrc.redshift.photfloatE_zError on z (upper value)stat.error;stat.maxfloatchi2N{chi}^2^ value for "No Ly{alpha}" case (2)stat.fit.chi2floatf_chi2N[+] Confused IRAC photometry (3)meta.codecharAVNAbsorption in V band for "No Ly{alpha}" case (2)magphys.absorptionfloatZN[0.2/1] Z abundance for "No Ly{alpha}" case (2)log(Sun)src.redshiftfloatzN[6.3/7.7] Redshift for "No Ly{alpha}" case (2)src.redshift.photfloatchi2W{chi}^2^ value for "With Ly{alpha}" case (2)stat.fit.chi2floatEW0Rest-frame Ly{alpha} equivalent width for "With Ly{alpha}" case (2)0.1nmspect.line.eqWidthintAVW[0/1] Absorption in V band for "With Ly{alpha}" case (2)magphys.absorptionfloatZW[0.2/1] Z abundance for "With Ly{alpha}" case (2)log(Sun)src.redshiftfloatSpTBest-fitting stellar templatesrc.spTypecharchi2{chi}^2^ value of best-fitting stellar templatestat.fit.chi2floatFWHMz'[0/9]? FWHM for z' band (4)arcsecphys.angSizefloatnullableFWHMY[0/9]? FWHM for Y band (4)arcsecphys.angSizefloatnullableFWHMJ[0/9]? FWHM for J band (4)arcsecphys.angSizefloatnullableB12Bowler et al. (2012MNRAS.426.2772B, [BDM2012] NNNNNN) galaxy number or H for 'Himiko' galaxy from Ouchi et al. (2013ApJ...778..102O) (5)meta.idchar