J/ApJS/185/20ivo://CDS.VizieR/J/ApJS/185/20doi:10.26093/cds/vizier.21850020CDSSyphers D.Anderson S.F.Zheng W.Haggard D.Meiksin A.,Schneider D.P.York D.G.2017-11-06T12:23:08Z2010-05-04T09:58:29ZCDS support team

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

cds-question@unistra.frquasarsultraviolet-photometryredshiftedsurveysAbsorption along quasar sightlines remains among the most sensitive direct measures of HeII reionization in much of the intergalactic medium (IGM). Until recently, fewer than a half-dozen unobscured quasar sightlines suitable for the HeII Gunn-Peterson test were known; although these handful demonstrated great promise, the small sample size limited confidence in cosmological inferences. We have recently added nine more such clean HeII quasars, exploiting Sloan Digital Sky Survey (SDSS) quasar samples, broadband ultraviolet (UV) imaging from Galaxy Evolution Explorer (GALEX), and high-yield UV spectroscopic confirmations from Hubble Space Telescope (HST). Here we markedly expand this approach by cross-correlating SDSS DR7 and GALEX GR4+5 to catalog 428 SDSS and 165 other quasars with z>2.78 having likely (~70%) GALEX detections, suggesting they are bright into the far-UV. Reconnaissance HST Cycle 16 Supplemental prism data for 29 of these new quasar-GALEX matches spectroscopically confirm 17 as indeed far-UV bright. At least 10 of these confirmations have clean sightlines all the way down to HeII Ly{alpha}, substantially expanding the number of known clean HeII quasars, and reaffirming the order of magnitude enhanced efficiency of our selection technique. Combined confirmations from this and our past programs yield more than 20 HeII quasars, quintupling the sample. These provide substantial progress toward a sample of HeII quasar sightlines large enough, and spanning a sufficient redshift range, to enable statistical IGM studies that may avoid individual object peculiarity and sightline variance. Our expanded catalog of hundreds of high-likelihood far-UV-bright QSOs additionally will be useful for understanding the extreme-UV properties of the quasars themselves.2009ApJS..185...20Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/185/20CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)VII/258 : Quasars and Active Galactic Nuclei (13th Ed.) (Veron+ 2010)J/AJ/133/1780 : GALEX/SDSS quasar catalog (Trammell+, 2007)J/ApJ/664/53 : UV photometry of GALEX QSO candidates (Atlee+, 2007)J/ApJ/690/1181 : New HII quasar sightlines (Syphers+, 2009)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/185/20https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/185/20http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/185/20https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/185/20https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/185/20http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/185/20GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/185/20/table1 (Catalog of candidate EUV-bright SDSS/GALEX quasars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/185/20/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/185/20/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/185/20/table1?GETtext/xml+votable180.050000true0.76394306-10.864078890.005555555555555556Cone search capability for table J/ApJS/185/20/table2 (Catalog of candidate EUV-bright (non-SDSS) VCV/GALEX quasars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/185/20/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/185/20/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/185/20/table2?GETtext/xml+votable180.050000true1.739614.26280.0055555555555555566/0 419 2688 4096 4099 4120 4123 4124 4170 4174 4192 4233 4252 4270 4299 4313 4322 4348 4353 4378 4381 4667 4678 4686 4693 4698 4704 4788 4814 4856 4880 4889 4948 4950 4955 4967 4971 4976 5012 5083 5107 5118 5145 5184 5230 5241 5260 5282 5289 5300 5329 5349 5352 5359 5395 5398 5400 5420 5460 5477 5524 5560 5588 5605 5614 5653 5654 5656 5674 5698 5733 5742 5783 5800 5809 5842 5844 5858 5931 5946 5947 5985 6042 6047 6069 6071 6075 6089 6106 6120 6226 6231 6262 6433 6469 6484 6501 6520 6556 6604 6619 6620 6650 6913 7190 7191 7210 7232 7258 7262 7268 7297 7348 7380 7440 7445 7606 8202 8205 8234 8249 8255 8276 8330 8344 8345 8347 8350 8414 8425 8437 8466 8486 8507 8521 8540 8630 8722 8735 8736 8901 8902 8904 8913 8932 9019 9044 9093 9114 9121 9122 9135 9164 9173 9195 9208 9212 9343 9375 9389 9415 9457 9465 9471 9515 9609 9781 9789 9790 9800 9869 9943 9958 9989 9990 9997 10019 10113 10145 10214 10247 10291 10300 10381 10383 10394 10405 10434 10463 10475 10512 10530 10567 10573 10577 10590 10615 10674 10688 10703 10707 10710 10712 10718 10720 10833 10887 10888 10897 10911 10921 10931 10937 10954 10976 10979 10992 10994 10995 11037 11056 11104 11106 11107 11136 11146 11160 11169 11173 11183 11214 11230 11239 11252 11286 11337 11363 11377 11389 11435 11454 11460 11529 11765 11906 11918 11934 12381 12399 16461 16467 16475 16532 16538 16539 16540 16643 16645 16646 16652 16656 17032 17151 17213 17294 17509 17517 17518 17564 17574 17662 17757 17758 17772 17773 17809 17820 17821 17825 17834 17841 17849 18019 18023 18027 18028 18042 18065 18069 18078 18083 18087 18090 18124 18227 18295 18387 18388 18389 18521 18542 18544 18776 18777 18782 18783 18787 18790 18791 18796 18800 18831 18835 18839 18843 18845 18854 18950 19007 19046 19052 19053 19060 19673 19686 19688 19691 19751 19987 20005 21847 21982 21990 23054 23206 23210 23211 23213 25851 25915 25917 25918 25924 25936 25946 25958 25961 25964 26002 26021 26023 26035 26041 26047 26064 26069 26080 26088 26094 26099 26177 26181 26193 26209 26217 26245 26247 26256 26257 26269 26270 26283 26291 26305 26327 26344 26358 26362 26382 26421 26429 26433 26448 26464 26492 26511 26514 26515 26520 26522 26990 26993 27035 27036 27046 27074 27199 27203 27238 27246 27345 27349 27363 27369 27390 27394 27424 27429 27459 27463 27470 27486 27508 27515 27519 27561 27612 27646 27714 27761 27769 27784 27786 27868 27937 27939 27944 27951 27963 27990 28004 28012 28038 28041 28058 28069 28076 28153 28167 28175 28201 28222 28251 28267 28383 28446 28450 28473 28478 28509 28534 28535 28536 28561 28571 28572 28603 28609 28610 28611 28627 28632 28648 28671 29718 30031 30033 31333 31375 31402 31475 31623 31667 32442 32502 33597 33746 33994 34148 34252 34287 34635 35027 35071 35121 35238 35243 35244 35246 35249 35252 35254 35257 35259 35272 35309 35413 35418 35422 35438 35439 35446 35483 35505 35508 35512 35521 35540 35547 35549 35551 35556 35557 35558 35571 35573 35580 35581 35583 35589 35590 35597 35623 35646 35729 35744 35760 35763 35765 35774 35778 35947 36019 36079 36101 36805 38872 43920 45038 45046 45049 45052 45621 46394 46418 46442 46587 46704 46723 46867 46950 46978 46993 46997 47004 47011 47485 48492 485062.040811542443644e-19 2.3647030891844645e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/185/20?format=asciiUVOpticaldefaultJ/ApJS/185/20/table1Catalog of candidate EUV-bright SDSS/GALEX quasarsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSDSSSDSS DR7 name (JHHMMSS.ss+DDMMSS.s)meta.id;meta.maincharzSDSS pipeline redshift (photometric)src.redshiftfloatzmag? SDSS z-band magnitudemagphot.mag;em.opt.IfloatnullableNUV? GALEX NUV flux (177-300nm)1e-19W.m**-2.nm**-1phot.flux;em.UVfloatnullableFUV? GALEX FUV flux (120-177nm)1e-19W.m**-2.nm**-1phot.flux;em.UVfloatnullableInsp[0/10] Inspection flag (1)src.classintObs[0/3] Prior observation flag (G2)meta.codeintSloanDisplay the SDSS data for this quasarmeta.ref.urlcharRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainJ/ApJS/185/20/table2Catalog of candidate EUV-bright (non-SDSS) VCV/GALEX quasarsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameVeron-Cetty & Veron (VCV) name (Cat. <VII/258>)meta.id;meta.maincharzVCV redshift (spectroscopic)src.redshiftfloatf_VmagBand of Vmag when not V (1)meta.codecharVmagVCV V-band magnitudemagphot.mag;em.opt.VfloatNUV? GALEX NUV flux (177-300nm)1e-19W.m**-2.nm**-1phot.flux;em.UVfloatnullableFUV? GALEX FUV flux (120-177nm)1e-19W.m**-2.nm**-1phot.flux;em.UVfloatnullableObs[0/3] Prior observation flag (G2)meta.codeintVCVSimbad column added by the CDSmeta.ref.urlcharRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.main