J/MNRAS/434/163ivo://CDS.VizieR/J/MNRAS/434/163doi:10.26093/cds/vizier.74340163CDSHacker T.L.Brunner R.J.Lundgren B.F.York D.G.2024-07-22T20:13:37Z2014-03-08T16:29:01ZCDS support team

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

cds-question@unistra.frquasarsredshiftedline-intensitiesWe present the results from a time domain study of absorption lines detected in quasar spectra with repeat observations from the Sloan Digital Sky Survey Data Release 7 (SDSS DR7). Beginning with over 4,500 unique time separation baselines of various absorption line species identified in the SDSS DR7 quasar spectra, we create a catalogue of 2,522 quasar absorption line (QAL) systems with two to eight repeat observations, representing the largest, unbiased, and homogeneous collection of multi-epoch absorption systems ever published. To investigate these systems for time-variability of narrow absorption lines, we refine this sample based on the reliability of the system detection, the proximity of pixels with bright sky contamination to individual absorption lines, and the quality of the continuum fit. Variability measurements of this sub-sample based on the absorption line equivalent widths yield a total of 33 systems with indications of significantly variable absorption strengths on time-scales ranging from one day to several years in the rest frame of the absorption system. Of these, at least 10 are from a class known as intervening absorption systems caused by foreground galaxies along the line of sight to the background quasar. This is the first evidence of possible absorption line variability detected in intervening systems, and their short time-scale variations suggest that small-scale structures (~10-100AU) are likely to exist in their host foreground galaxies.2013MNRAS.434..163Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/434/163CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/260 : The SDSS-DR7 quasar catalog (Schneider+, 2010)J/MNRAS/405/2302 : Improved redshifts for SDSS quasar spectra (Hewett+, 2010)http://www.sdss.org : SDSS Home Pagehttp://casjobs.sdss.org/CasJobs/ : SDSS CAS Home Pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/434/163https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/434/163http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/434/163https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/434/163https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/434/163http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/434/163GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/434/163/table2 (Catalogue of Quasar Absorption Line (QAL) systems with repeat observations)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/434/163/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/434/163/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/434/163/table2?GETtext/xml+votable180.050000true0.17879970.92768970.005555555555555556Cone search capability for table J/MNRAS/434/163/table3 (Variable NAL systems (Narrow-Line absorption))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/434/163/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/434/163/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/434/163/table3?GETtext/xml+votable180.050000true125.1415743.46439690.0055555555555555565/1026 1147 1627 1639 1813 2368 2378 2400 2474 2518 2595 2683 2838 2872 4437-4438 4441-4442 4457 4506 4517 4709 4937 5797-5798 6485 6489-6490 6502 6545 6551 6741 6/0-2 552 4096-4098 4126 4134 4137-4138 4143 4154 4165 4167 4173 4192 4195-4196 4199 4225-4228 4230 4250 4254 4287 4302 4322 4331 4415 4456 4464 4473 4476 4504 4509 4524 4531 4534 4549 4564 4579 4583-4585 4587 4642 4667 4687 4691 4698 4724 4732 4749 4753 4760 4769 4772 4793 4820 4823 4828 4837 4844 4859 4895 4913 4920 4929-4930 4932 4935 4947 4951 4957 4965 4967 4979 4987-4988 4991 5012 5022 5041 5046-5047 5054-5055 5062 5080 5095 5104-5105 5107-5108 5148 5179 5182 5196 5199 5228-5230 5248 5264-5265 5267-5268 5270-5271 5273 5293-5294 5305 5328 5333 5352 5355 5380-5381 5420-5421 5435 5441 5447 5459 5471 5505 5508-5509 5543 5637 5660 5696 5731 5742 5753-5754 5779 5797 5810 5826 5831 5840 5848 5884 5887 5897 5906 5912 5987 6014 6092 6097 6099-6100 6108 6110-6111 6117 6133 6217 6220 6222 6255-6257 6262 6356-6357 6359 6363 6397 6405-6406 6473 6502-6503 6505 6507 6523 6525 6527-6529 6536 6551 6553-6555 6577 6580 6593-6595 6597-6599 6605 6608 6617-6619 6622 6640-6641 6644 7208 7210 7239 7248 7251 7257 7260 7263 7287 7291 7293 7296-7297 7322 7331-7334 7344 7346 7362-7364 7366-7369 7371 7432 7434 7441-7443 7445 7452 7454 7456 7468 7482 7484 7489 7494 7496 7500 7503 7515 7520-7521 7523 7525 7555 7558 8192-8193 8195 8202-8204 8206-8207 8225 8228 8230-8231 8518-8519 8525 8527 8530-8531 8537 8542 8564 8566 8569 8669 8841 8860 8889 9071 9129-9130 9132 9134-9135 9148 9221 9236 9243 9245 9271 9279 9290 9300 9302-9303 9309 9335 9341 9343 9429 9431 9437 9443 9459 9468 9506 9516 9518 9612-9613 9618 9732 9734 9803 9818 9831 9839-9840 9843-9846 9851 9853 9894 9900 9918 9949 9960 9970 9975 9981 10067 10085-10087 10092 10094-10098 10114 10123 10177 10180 10191 10200 10214 10217 10219-10220 10222 10249 10256 10319 10356-10357 10375 10392 10394 10405 10496-10497 10499-10500 10544 10611 10622 10672 10693 10727 10731 10744-10746 10756 10758 10760-10761 10766 10771 10803 10883 10886 10900 10906 10914 10922 10937 10964 10967 10988 11006 11079 11125 11127 11136-11137 11139 11220 11224 11229 11243 11245-11247 11249 11256 11258-11259 11265 11275 11289 11319 11328 11333 11336 11343 11346-11347 11365-11366 11373 11376-11377 11379 11384-11385 11423 11435 11445-11446 11449 11452-11453 11464 11470 11476 11495 11503 11512 11514 11585 11786-11787 11790 11798 11804 11808-11809 11812 11814 11827 11836 11840 11845 11848 11856 11882-11883 11904 11907 11913 11917 11968 17223 17231 17240 17242 17252 17264 17298 17307 17406-17407 17469-17471 17508 17511-17514 17518 17560 17601 17604 17663 17725-17726 17741 17743 17745 17747 17756-17758 17761 17763 17772-17774 17777-17778 17806-17807 17811-17813 17816-17818 17821 17826-17827 17832-17833 17835-17836 17840 17857 17860 17981-17982 18001-18002 18005 18007 18010-18011 18018-18019 18028-18030 18032 18063 18065 18067 18072 18074 18076-18077 18083 18086-18089 18091-18092 18094 18096 18098 18113 18176-18177 18301 18367 18381 18383 18385 18389 18393-18395 18405 18407-18408 18411 18416-18417 18521-18522 18540 18603 18606-18607 18750 18765-18767 18770-18774 18777-18780 18782 18787-18790 18792-18794 18796 18798 18800 18802 18804 18830 18833 18835 18841-18845 18849 18852-18853 18858 18866 18880-18882 18945 18947-18949 18951 19031 19049 19094-19095 19100 19201 19408-19409 19456 19726-19727 19733 19735 19738-19740 19745 19755-19757 19759-19762 19768 19776 21981 22001 22005 22361 22365 23054 23059 23103 23146 23182-23183 23187 23196-23198 23201-23203 23205-23207 23210-23212 23214 23216 23232 23234 25567 25838 25854 25907 25933-25935 25937-25939 25947-25950 25954-25955 25968-25970 25997 25999 26001-26003 26012-26013 26017 26020-26021 26023 26029 26032-26034 26049-26050 26057 26174-26175 26177 26189 26196-26197 26225 26235 26245 26253 26255 26261 26263 26282 26304-26305 26321 26368 26370 26389 26467 26606 26943 26954 26958-26959 26961 26972 26980-26982 26986 26989 26992 26994 27034 27038 27074 27199 27228-27229 27239 27244-27246 27248 27253 27260-27261 27285 27308-27309 27313-27314 27320 27328 27330 27332 27339 27346 27349 27363 27462 27467-27468 27470 27489 27543 27562 27565 27567 27648-27650 27855 27919 27929 28001 28006 28009 28014 28036 28073 28076 28102 28158 28160 28501 28503 28540 28543 28595 28610 28614 28618 28649 28670 30029 30040 31293-31294 31359 31373-31374 31377 31382 31388 31390 31396 31405-31406 31409 31426 31430-31431 31435-31437 31439 31446 31448 31454 31616 31620 31627 31648 31704-31706 31716 31726-31727 31729 31738 31743 32397 32415 32458 32462 32482 32484 32486 32489 32502 32511 32680 32682 36718 36726 36775 36782-36783 36786 36792 36800 36809 36862-36863 40959 45049 45053-45055 49009 49012-49013 49015 49020 49078https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/434/163?format=asciiOpticaldefaultJ/MNRAS/434/163/table2Catalogue of Quasar Absorption Line (QAL) systems with repeat observationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSDSSSDSS object designation (HHMMSS.ss+DDMMSS.s)meta.id;meta.maincharprimaryNspNumber of spectra for this QALmeta.numberintnullableSysIdentification of system when belongs to a variable NAL system (table3)meta.ref.urlintRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainzqso[0.3/4.5] Quasar redshift (Hewett & Wild 2010, Cat. J/MNRAS/405/2302)src.redshift;pos.heliocentricfloatzabsi[0.3/3.7] Absorption system redshiftsrc.redshiftfloatbetaAbsorption system velocity {beta}=v/c (in quasar rest frame)phys.velocdoublePlateSDSS spectroscopic plate numbermeta.id;instr.plateintMJDSDSS Modified Julian Date (MJD) of observationdtime.epochintFiberSDSS spectroscopic fiber numbermeta.number;pos.parallax.spectintGradeAbsorption system confidence grade (1)meta.code.qualcharNlNumber of lines identified in the spectrummeta.numberintmSimbad column added by the CDSmeta.notecharLinesDetected absorption lines (2)meta.id;spect.linecharlistList all lines detectedmeta.ref.urlcharSloanDisplay the SDSS data for this quasarmeta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlcharJ/MNRAS/434/163/table3Variable NAL systems (Narrow-Line absorption)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSys[1/33] System number indexmeta.idintSDSSSDSS object designation (HHMMSS.ss+DDMMSS.s)meta.id;meta.maincharNNumber of elements in this NAL systemmeta.numberintnullableRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainzqso[1.2/3.9] Quasar redshift (Hewett & Wild 2010, Cat. J/MNRAS/405/2302)src.redshift;pos.heliocentricfloatzabs[0.6/3.0] Narrow Absorption Line (NAL) system redshiftsrc.redshiftfloatbetaNAL system velocity ({beta}=v/c in quasar rest frame)phys.velocdoublePlate1SDSS plate number - first observationmeta.id;instr.plateintFiber1SDSS fibre number - first observationmeta.noteintMJD1SDSS MJD - first observationdobs.param;obsintPlate2SDSS plate number - second observationmeta.id;instr.plateintFiber2SDSS fibre number - second observationmeta.noteintMJD2SDSS MJD - second observationdobs.param;obsinttrestTime between observations (quasar rest frame)dtime.intervaldoubleIonAbsorption line ionphys.atmol.ionStagecharlam0Absorption line rest wavelength {lambda}_0_0.1nmem.wlfloatEW1Equivalent width - first observation0.1nmspect.line.eqWidth;obsfloate_EW1Equivalent width error - first observation0.1nmstat.errorfloatf_EW1Absorption line flag - first observation (3)meta.codecharEW2Equivalent width - second observation0.1nmspect.line.eqWidth;obsfloate_EW2Equivalent width error - second observation0.1nmstat.errorfloatf_EW2Absorption line flag - second observation (3)meta.codecharSloan1Display the SDSS data for this quasarmeta.ref.urlcharSloan2Display the SDSS data for this quasarmeta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlchar