J/ApJ/819/24ivo://CDS.VizieR/J/ApJ/819/24doi:10.26093/cds/vizier.18190024CDSWang F.Wu X.-B.Fan X.Yang J.Yi W.Bian F.McGreer I.D.Yang Q.,Ai Y.Dong X.Zuo W.Jiang L.Green R.Wang S.Cai Z.Wang R.,Yue M.2018-02-01T06:28:36Z2016-06-15T09:23:26ZCDS support team

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

cds-question@unistra.frquasarsredshiftedvisible-astronomysloan-photometryinfrared-photometryspectroscopyHigh-redshift quasars are important tracers of structure and evolution in the early universe. However, they are very rare and difficult to find when using color selection because of contamination from late-type dwarfs. High-redshift quasar surveys based on only optical colors suffer from incompleteness and low identification efficiency, especially at z>~4.5. We have developed a new method to select 4.7<~z>~5.4 quasars with both high efficiency and completeness by combining optical and mid-IR Wide-field Infrared Survey Explorer (WISE) photometric data, and are conducting a luminous z~5 quasar survey in the whole Sloan Digital Sky Survey (SDSS) footprint. We have spectroscopically observed 99 out of 110 candidates with z-band magnitudes brighter than 19.5, and 64 (64.6%) of them are quasars with redshifts of 4.4<~z<~5.5 and absolute magnitudes of -29<~M_1450_<~-26.4. In addition, we also observed 14 fainter candidates selected with the same criteria and identified 8 (57.1%) of them as quasars with 4.7<z<5.4. Among 72 newly identified quasars, 12 of them are at 5.2<z<5.7, which leads to an increase of ~36% of the number of known quasars at this redshift range. More importantly, our identifications doubled the number of quasars with M_1450_<-27.5 at z>4.5, which will set strong constraints on the bright end of the quasar luminosity function. We also expand our method to select quasars at z>~5.7. In this paper we report the discovery of four new luminous z>~5.7 quasars based on SDSS-WISE selection.2016ApJ...819...24Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/819/24CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/270 : SDSS quasar catalog: tenth data release (Paris+, 2014)II/328 : AllWISE Data Release (Cutri+ 2013)II/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)II/311 : WISE All-Sky Data Release (Cutri+ 2012)V/139 : The SDSS Photometric Catalog, Release 9 (Adelman-McCarthy+, 2012)VII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010)VII/258 : Quasars and Active Galactic Nuclei (13th Ed.) (Veron+ 2010)VII/241 : The 2dF QSO Redshift Survey (Croom+ 2004)J/ApJS/219/39 : QSOs selection from SDSS and WISE (Richards+, 2015)J/MNRAS/450/3893 : SDSS DR10 catalogue of candidate quasars (Brescia+, 2015)J/A+A/583/A75 : Large Quasar Astrometric Catalogue 3 (LQAC-3) (Souchay+, 2015)J/ApJ/768/105 : z~5 QSO LF from SDSS Stripe 82 (McGreer+, 2013)J/AJ/144/49 : Quasars from SDSS-DR7, WISE and UKIDSS surveys (Wu+, 2012)J/ApJS/200/8 : AGES: the AGN and Galaxy Evolution Survey (Kochanek+, 2012)J/ApJS/197/19 : First brown dwarfs discovered by WISE (Kirkpatrick+, 2011)J/ApJS/194/45 : QSO properties from SDSS-DR7 (Shen+, 2011)J/ApJ/699/782 : High-redshift SDSS-DR5 QSOs (Diamond-Stanic+, 2009)J/ApJS/166/470 : SDSS-Spitzer type I QSOs IR photometry (Richards+, 2006)J/ApJ/640/579 : Near-infrared spectra of 27 SDSS quasars (Glikman+, 2006)J/AJ/122/503 : QSO SDSS u*g*r*i*z* photometry & redshifts (Anderson+, 2001)J/AJ/121/31 : High-redshift quasars in SDSS (Fan+, 2001)http://www.sdss3.org/ : SDSS-III home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/819/24https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/819/24http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/819/24https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/819/24https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/819/24http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/819/24GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/819/24/highzqso (Observational information and photometric properties of 72 newly identified z~5 quasars (tables 2 and 3))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/819/24/highzqso?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/819/24/highzqso?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/819/24/highzqso?GETtext/xml+votable180.050000true1.9753333-3.29189440.005555555555555556Cone search capability for table J/ApJ/819/24/table1 (Optical and WISE photometry of 725 published z>4.5 quasars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/819/24/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/819/24/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/819/24/table1?GETtext/xml+votable180.050000true0.66412525.84303890.0055555555555555566/0 33 34 42 46 424 522 717 2080 2154 2187 2247 2276 2515 2520 2584 2611 4101 4157 4176 4224 4242 4247 4250 4279 4339 4352 4356 4384 4415 4456 4466 4472 4475 4495 4507 4545 4582 4619 4626 4627 4641 4646 4662 4709 4727 4729 4745 4754 4822 4830 4872 4881 4892 4905 4912 4924 4931 4947 4954 4957 4986 5000 5001 5016 5059 5061 5065 5066 5072 5091 5098 5121 5125 5139 5153 5170 5186 5199 5216 5229 5230 5266 5267 5272 5295 5333 5347 5393 5398 5400 5404 5407 5423 5425 5440 5451 5458 5467 5473 5510 5517 5528 5537 5566 5574 5630 5635 5654 5664 5710 5723 5752 5769 5777 5779 5801 5810 5826 5833 5858 5874 5906 5913 5923 5928 5990 6050 6071 6073 6077 6081 6090 6096 6112 6129 6172 6196 6238 6342 6415 6427 6482 6500 6547 6552 6581 6589 6917 6933 7171 7183 7197 7220 7230 7293 7326 7378 7393 7459 7464 7478 7522 7526 7569 7600 7942 8197 8202 8211 8213 8219 8227 8238 8257 8269 8299 8301 8319 8323 8329 8333 8348 8354 8363 8388 8404 8452 8463 8481 8486 8495 8501 8515 8542 8553 8606 8626 8641 8655 8662 8670 8681 8710 8713 8715 8722 8726 8736 8787 8794 8813 8819 8825 8828 8829 8843 8845 8846 8876 8878 8888 8945 8971 9075 9084 9104 9115 9144 9146 9151 9164 9195 9218 9222 9263 9275 9278 9285 9319 9333 9373 9388 9394 9412 9439 9469 9523 9615 9659 9716 9733 9735 9740 9748 9754 9781 9816 9818 9831 9847 9855 9882 9892 9902 9923 9966 9967 9973 9981 9999 10020 10024 10027 10092 10121 10123 10145 10193 10197 10242 10246 10254 10255 10257 10318 10334 10336 10342 10373 10379 10386 10388 10390 10451 10456 10466 10497 10501 10508 10509 10512 10516 10518 10520 10535 10553 10578 10583 10598 10609 10616 10653 10656 10665 10686 10734 10756 10759 10780 10783 10788 10796 10803 10914 10919 10932 10933 10939 10948 10988 11014 11027 11030 11048 11051 11087 11116 11121 11128 11143 11147 11161 11165 11252 11267 11283 11287 11317 11371 11382 11392 11393 11429 11440 11446 11460 11471 11473 11492 11520 11787 11798 11907 11916 11945 12299 12402 12567 13418 13683 15578 16531 16831 17068 17239 17252 17362 17374 17649 17663 17668 17677 17679 17681 17684 17690 17691 17701 17706 17726 17742 17743 17749 17756 17757 17767 17770 17772 17800 17805 17809 17812 17813 17816 17817 17820 17844 17872 17890 17898 17989 17993 17997 18005 18006 18009 18010 18018 18028 18031 18061 18063 18064 18067 18071 18076 18077 18084 18088 18091 18155 18177 18181 18222 18242 18378 18403 18516 18627 18638 18642 18685 18686 18717 18742 18751 18766 18770 18773 18779 18780 18787 18789 18791 18792 18833 18836 18839 18855 18857 18859 18860 18862 18880 18882 18945 19008 19025 19027 19028 19030 19032 19033 19034 19036 19046 19048 19049 19060 19067 19093 19099 19104 19109 19110 19111 19116 19137 19158 19200 19202 19214 19217 19242 19374 19412 19436 19440 19525 19564 19676 19690 19693 19704 19728 19754 19787 19863 19989 20010 20037 20116 20145 20273 20388 20390 20441 21850 21872 21989 22006 22384 22393 22826 23078 23102 23103 23147 23150 23181 23191 23193 23194 23203 23210 23216 23274 23838 25330 25340 25375 25540 25669 25849 25887 25911 25937 25938 25947 25959 25965 25969 25977 25979 25987 25995 26020 26031 26080 26204 26215 26221 26233 26239 26262 26279 26280 26281 26282 26318 26328 26336 26344 26351 26358 26380 26381 26422 26451 26479 26497 26524 26527 26542 26567 26589 26596 26621 26677 26715 26846 26861 26933 26943 26955 26956 26959 26972 26978 26990 27025 27027 27041 27061 27084 27118 27124 27135 27256 27258 27278 27298 27324 27356 27359 27367 27372 27376 27426 27440 27452 27459 27481 27500 27508 27526 27576 27610 27615 27618 27624 27641 27659 27665 27681 27694 27696 27699 27700 27702 27703 27781 27826 27828 27833 27860 27876 27901 27926 27974 28008 28023 28025 28027 28047 28049 28065 28067 28078 28080 28081 28119 28144 28178 28190 28256 28291 28294 28321 28382 28387 28390 28396 28401 28405 28419 28425 28452 28467 28468 28490 28498 28499 28504 28506 28530 28537 28557 28560 28572 28594 28612 28614 28639 28657 30035 30036 30037 30039 30065 31310 31375 31379 31408 31482 31529 31539 31629 31631 31652 31660 31705 31712 32396 32436 32438 32466 32478 32489 32492 32508 32511 32683 33746 34187 34512 34850 35304 35615 35727 35895 35909 35952 36007 36083 36631 36725 36792 36810 40938 44391 44399 44463 44595 44743 44833 46449 48423 488993.830199579824256e-20 3.5010283109654867e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/819/24?format=asciiInfraredOpticaldefaultJ/ApJ/819/24/highzqsoObservational information and photometric properties of 72 newly identified z~5 quasars (tables 2 and 3)SimbadNameSimbad column added by the CDSmeta.idcharSloanDisplay the online SDSS data for the nearest objectmeta.ref.urlcharTelTelescope code (2)meta.code;instr.telcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameSource identifier (JHHMMSS.ss+DDMMSS.ss) (G1)meta.id;meta.maincharGratingGrating used on Telinstr.setupcharSlit[1/2.5] Slit widtharcsecspect.line.widthfloatz[4.4/5.6] Spectroscopic redshiftsrc.redshiftfloatDateUT date of the observationtime.epoch;obsnullableExp[200/3600] Exposure timestime.duration;obs.exposureintf_Name[a] Flag on Name (1)meta.codecharm1450[17.5/20.3] Apparent 1450{AA} AB magnitude (2)magphot.magfloatM1450[-29/-26] Absolute 1450{AA} AB magnitude (2)magphys.magAbsfloatrmag[19.5/22.5] SDSS r-band AB magnitudemagphot.mag;em.opt.Rfloate_rmag[0.02/0.3] Error in rmagmagstat.error;phot.mag;em.opt.Rfloatimag[17.9/20.5] SDSS i-band AB magnitudemagphot.mag;em.opt.Ifloate_imag[0.01/0.05] Error in imagmagstat.error;phot.mag;em.opt.Ifloatzmag[17.4/20.1] SDSS z-band AB magnitudemagphot.mag;em.opt.Ifloate_zmag[0.02/0.2] Error in zmagmagstat.error;phot.mag;em.opt.IfloatW1mag[14.3/17] WISE W1-band (3.4um) magnitudemagphot.mag;em.IR.3-4umfloate_W1mag[0.03/0.3] Error in W1magmagstat.error;phot.magfloatW2mag[13.4/16.2] WISE W2-band (4.6um) magnitudemagphot.mag;em.IR.4-8umfloate_W2mag[0.03/0.2] Error in W2magmagstat.error;phot.magfloatR15Display data from Richards+, 2015, J/ApJS/219/39, within 2"meta.ref.urlintnullableDR9Display the SDSS-DR9 photometric catalog (V/139) within 1"meta.ref.urlcharWISEDisplay the WISE all-sky (Cutri+, 2012, II/311) and the AllWISE data (Cutri+, 2013, II/328) within 1"meta.ref.urlcharNEDNED column added by the CDSmeta.ref.urlchar_RAPositions from Names (right ascension part)degpos.eq.ra;meta.main_DEPositions from Names (declination part)degpos.eq.dec;meta.mainJ/ApJ/819/24/table1Optical and WISE photometry of 725 published z>4.5 quasarsSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameSource identifier (JHHMMSS.ss+DDMMSS.ss)meta.id;meta.maincharz[4.5/7.1] Spectroscopic redshift from discovery papersrc.redshiftfloatRef1References of discovery paper (see refs.dat file)meta.ref;pos.framecharrmag[18.2/27.6]? SDSS corrected r-band magnitude (1)magphot.mag;em.opt.Rfloatnullablee_rmag[0.01/1.6]? Error in rmagmagstat.error;phot.mag;em.opt.Rfloatnullableimag[17.2/28]? SDSS corrected i-band magnitude (1)magphot.mag;em.opt.Ifloatnullablee_imag[0.01/2.2]? Error in imagmagstat.error;phot.mag;em.opt.Ifloatnullablezmag[17.4/26]? SDSS corrected z-band magnitude (1)magphot.mag;em.opt.Ifloatnullablee_zmag[0.01/1.1]? Error in zmagmagstat.error;phot.mag;em.opt.IfloatnullableRef2Reference for optical magnitudes ("SDSS" or "REF")meta.ref;pos.framecharW1mag[13.5/19]? WISE W1-band (3.4um) magnitudemagphot.mag;em.IR.3-4umfloatnullablee_W1mag[0.03/0.6]? Error in W1magmagstat.error;phot.magfloatnullableW2mag[13.1/17.6]? WISE W2-band (4.6um) magnitudemagphot.mag;em.IR.4-8umfloatnullablee_W2mag[0.03/0.6]? Error in W2magmagstat.error;phot.magfloatnullableRef3Reference for WISE magnitude (2)meta.ref;pos.framecharR15Display data from Richards+, 2015, J/ApJS/219/39, within 2"meta.ref.urlintnullableDR9Display the SDSS-DR9 photometric catalog (V/139) within 1"meta.ref.urlcharWISEDisplay the WISE all-sky (Cutri+, 2012, II/311) and the AllWISE data (Cutri+, 2013, II/328) within 1"meta.ref.urlcharSloanDisplay the online SDSS data for the nearest objectmeta.ref.urlcharNEDNED column added by the CDSmeta.ref.urlchar_RAPositions from Names (right ascension part)degpos.eq.ra;meta.main_DEPositions from Names (declination part)degpos.eq.dec;meta.mainJ/ApJ/819/24/refsReferencesRefReference codemeta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBibCodeBibcode of the referencemeta.bib.bibcodecharCommCommentmeta.notechar