J/ApJ/888/85ivo://CDS.VizieR/J/ApJ/888/85doi:10.26093/cds/vizier.18880085CDSFathivavsari H.2021-10-25T10:15:53Z2021-07-19T08:38:07ZCDS support team

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

cds-question@unistra.frquasarsvisible-astronomyspectroscopyintergalactic-mediumredshiftedWe have searched the Sloan Digital Sky Survey Data Release 12 for ghostly strong Ly{alpha} (DLA) systems. These systems, located at the redshift of the quasars, show strong absorption from low-ionization atomic species but reveal no HI Ly{alpha} absorption. Our search has, for the first time, resulted in a sample of 30 homogeneously selected ghostly absorbers with z_QSO_>2.0. Thirteen of the ghostly absorbers exhibit absorption from other HI Lyman series lines. The lack of Ly{alpha} absorption in these absorbers is consistent with them being dense and compact with projected sizes smaller than the broad-line region of the background quasar. Although uncertain, the estimated median HI column density of these absorbers is logN(HI)~21.0. We compare the properties of ghostly absorbers with those of eclipsing DLAs that are high-column-density absorbers, located within 1500km/s of the quasar emission redshift and showing strong Ly{alpha} emission in their DLA trough. We discover an apparent sequence in the observed properties of these DLAs, with ghostly absorbers showing wider HI kinematics, stronger absorptions from high-ionization species, CII and SiII excited states, and a higher level of dust extinction. Since we estimate that all these absorbers have similar metallicities, logZ/Z_{sun}_~-1.0, we conclude that ghostly absorbers are part of the same population as eclipsing DLAs, except that they are denser and located closer to the central active galactic nuclei.2020ApJ...888...85Fhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/888/85CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/279 : SDSS quasar catalog: twelfth data release (Paris+, 2017)VII/289 : SDSS quasar catalog, sixteenth data release (DR16Q) (Lyke+, 2020)J/MNRAS/354/L31 : SDSS DR2 QSO and DLA properties (Murphy+, 2004)J/PASP/116/622 : SDSS damped Ly{alpha} survey: DR1 (Prochaska+, 2004)J/PASP/118/1077 : Metal-strong damped Ly{alpha} systems (Herbert-Fort+, 2006)J/ApJ/636/610 : Damped Ly{alpha} systems at z<1.65 (Rao+, 2006)J/ApJ/663/320 : IR-through-UV extinction curve (Fitzpatrick+, 2007)J/MNRAS/392/998 : Damped Lyman{alpha} systems (Ellison+, 2009)J/MNRAS/405/2302 : Improved redshifts for SDSS quasar spectra (Hewett+, 2010)J/A+A/547/L1 : SDSS-III DR9 DLA catalogue (Noterdaeme+, 2012)J/other/ApSS/353.347 : 398-710nm Sun spectral atlases (Fathivavsari+, 2014)J/AJ/149/203 : Reddening of ~35000 quasars from SDSS (Krawczyk+, 2015)J/MNRAS/462/3285 : XQ-100. X-shooter quasar spectra (Perrotta+, 2016)J/A+A/585/A87 : Quasar composite made from bright QSOs (Selsing+, 2016)J/MNRAS/464/L56 : DLA properties and EW of 36 QSOs (Berg+, 2017)J/MNRAS/477/5625 : SDSSDR12 eclipsing damped Lya systems (Fathivavsari+, 2018)J/A+A/618/A184 : SDSS J151349.52+035211.28 Xshooter spectra (Ranjan+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/888/85https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/888/85http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/888/85https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/888/85https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/888/85http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/888/85GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/888/85/table1 (Ghostly absorbers)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/888/85/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/888/85/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/888/85/table1?GETtext/xml+votable180.050000true2.432208313.34238890.005555555555555556Cone search capability for table J/ApJ/888/85/table2 (Search results)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/888/85/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/888/85/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/888/85/table2?GETtext/xml+votable180.050000true141.620416757.13138890.0055555555555555561/5 10 27 2/16-17 19 25 32-34 38 75-78 103 107 3/32 34 72-73 75 112-114 116 141-143 145-147 150 176-178 184 208 276-278 281-284 286-287 295 299 316-318 407 411 423 427 491 4/40 42-43 46 132-134 160 296-297 299 385 388-389 391 397 460-461 468-469 472 560-562 576-577 579 592 594-595 624 626 632 634 716 718 720 744-746 772 788-789 791 797 836-838 840-841 848 1078 1084-1085 1087 1095 1101-1103 1116 1118 1121-1123 1140 1142-1143 1173-1175 1177-1179 1189-1191 1193 1195 1276 1367 1373 1375 1397 1621-1623 1625-1627 1637-1639 1641-1643 1685-1687 1689-1691 1701-1702 1705-1707 1961-1963 1976 1978-1979 1982-1983 2026-2027 2030-2031 2299 2302 5/2 8 10 138 164 166-167 190 540 542 560-562 568 576 644 648 650 1192-1193 1195 1549 1560-1561 1563 1585 1596-1597 1599 1684-1685 1848-1850 1852-1854 1880-1881 1896 2252-2253 2255 2312 2314-2315 2372 2374-2375 2500 2502 2508 2510 2532 2534 2540 2868-2870 2876 2878 2888-2890 2960-2962 2968 2970 2988 3077 3079 3092-3094 3096 3141 3160-3161 3163 3185 3196-3197 3199 3356-3358 3368-3369 3376-3377 3396 4317-4319 4325 4345 4347 4374-4375 4377 4391 4397 4401-4403 4468-4470 4476 4478 4481 4483 4669-4671 4685-4687 4689-4691 4705-4707 4749-4751 4753-4755 4769-4771 4776-4777 4779 5108-5109 5112-5114 5461 5463 5465-5467 5477 5479 5488-5489 5491 5497 5499 5585 5596-5597 5599 5621 5623 6398-6399 6461-6463 6477-6479 6481-6483 6497-6499 6541-6543 6545 6547 6561-6563 6717-6719 6733-6735 6737-6739 6753-6755 6797-6799 6801-6803 6812 6814-6815 6817 6819 7839 7843 7882 7908 7910 7921-7924 7926-7927 8098-8099 8102-8103 8114-8115 8118-8119 8162 8168 8170-8171 8174 9191 9194-9195 9200 9202 9214 11261-11263 6/0 2-3 12 14-15 36-38 544 546 556 558-559 662-663 714-715 754 764 766-767 2164-2166 2172 2174 2252-2254 2256-2258 2264 2276 2280-2282 2312-2314 2336 2580-2582 2584-2586 2596-2598 2604 2688 4776-4777 4779 6148-6149 6151 6159 6181 6192-6193 6204-6205 6248-6249 6251 6337 6339 6345 6348-6349 6351 6393-6395 6912-6914 6916-6917 6919 6928-6930 6932-6933 6976-6977 6980-6981 6992-6993 6996-6997 7404-7406 7420-7422 7528-7530 7532 7536-7538 7568-7570 7572 7588 7592 7680-7681 7684-7685 7696 7744 9016 9018-9019 9252-9253 9255 9492 9494 9568 9570 9576 9578 9664 9666 9672 9674 10004-10006 10012 10014 10036 10038 10044 10046 10168-10170 11484 11486 11536 11538 11544 11546 11564-11566 11568 11648-11650 11652 11852-11854 11856 11858 11864 11876-11878 11884 11886 11956 11960 11968 11970 12293 12304-12305 12307 12313 12340-12341 12343 12380-12381 12388 12392 12544-12546 12560-12561 12572-12573 12575 12597 12599 12649 12651 12737 12749 12751 12773 12793 12795 13436-13438 13480 13484 13488-13489 13492 13512-13514 13520-13521 13588-13589 13592 13600-13602 13604 13632 17213-17215 17243 17245-17247 17265-17267 17297 17299 17308-17309 17311 17333 17376-17377 17487 17491 17493-17495 17517-17519 17579 17582-17583 17597-17599 17601-17603 17884 17908 17910 17916 17921 17928 17930-17931 18256 18258 18264 18266-18267 18270 18653-18655 18669-18671 18673-18675 18717-18719 18733-18735 18737-18739 18753-18755 18817-18819 18973-18975 18989-18991 18993-18995 19009-19011 19073-19075 19113 19115 20440 20442-20443 20464 21823 21839-21841 21843 21849-21851 21859 21907 21913 21915 21940 21960-21961 21963 22349 22351 22373 22393 22481 22519 25583 25587 25590 25821-25823 25837-25839 25841-25843 25886-25887 25901-25903 25905-25907 25923 25985-25987 26143 26159 26163 26179 26186-26187 26243 26847 26863 26865 26867 26911 26927 26931 26947 27009-27011 27167 27183 27187 27203 27253-27255 27267 27273-27275 31291-31292 31294-31295 31338 31351 31354-31355 31367 31370-31371 31522 31534-31535 31545-31547 31550-31551 31598-31599 31636 31638 31644 31646-31647 31681-31683 31700 31702-31703 32386 32390-32391 32451 32471 32642 32678-32679 32690 32702 36759 36761-36763 36773-36775 36806 36812 36814-36815 36848 36850-36851 36860 36862-36863 40949-40951 40957-40959 45023 45039 49117 49119 49141https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/888/85?format=asciiOpticaldefaultJ/ApJ/888/85/table1Ghostly absorbersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSDSSSDSS name (HHMMSS.ss+DDMMSS.s; J2000)meta.id;meta.maincharzQSO[2.038/3.39] Quasar emission redshiftsrc.redshift;pos.heliocentricfloatzabs[2.035/3.387] Ghostly absorber absorption redshiftsrc.redshiftfloatlogNHI[20.3/21.8]? Logarithm of HI column density (1)phys.columnDensityfloatnullableFeII1[39/2373]? Rest equivalent width (in m{AA}) of the FeII{lambda}1608 absorption line0.1pmspect.line.eqWidthintnullableFeII2[674/4319]? Rest equivalent width (in m{AA}) of the FeII{lambda}2382 absorption line0.1pmspect.line.eqWidthintnullableFeII3[569/5869]? Rest equivalent width (in m{AA}) of the FeII{lambda}2600 absorption line0.1pmspect.line.eqWidthintnullableAlII[278/3278]? Rest equivalent width (in m{AA}) of the AlII{lambda}1670 absorption line0.1pmspect.line.eqWidthintnullableMgII[1562/4414]? Rest equivalent width (in m{AA}) of the MgII{lambda}2796 absorption line0.1pmspect.line.eqWidthintnullableCII[1001/5105]? Rest equivalent width (in m{AA}) of the CII{lambda}1334 absorption line0.1pmspect.line.eqWidthintnullableFnu[0.5/5.8] Quasar flux in 10^-17^erg/s/cm^2^/{AA}1e-19W.m**-2.nm**-1phot.fluxfloatLnu[41.3/42.3] Logarithm of QSO luminosity at 1500{AA}phys.luminosityfloatSloanDisplay the online SDSS-DR14 data for the nearest objectmeta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlcharNEDNED column added by the CDSmeta.ref.urlchar_RAPosition from SDSS names (right ascension part)degpos.eq.ra;meta.main_DEPosition from SDSS names (declination part)degpos.eq.dec;meta.mainJ/ApJ/888/85/table2Search resultsSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDSDSS Plate-MJD-Fiber identifiermeta.id;meta.maincharz[2.04/5.47] Quasar spectroscopic redshiftsrc.redshiftdoubleS1Member of the S-1 subsample? (1)meta.codecharS2Member of the S-2 subsample? (1)meta.codecharS3Member of the S-3 subsample? (1)meta.codecharS4Member of the S-4 subsample? (1)meta.codecharS5Member of the S-5 subsample? (1)meta.codecharGhostMember of the ghostly absorbers?meta.codecharDR16QDisplay data from the SDSS-DR16Q catalog (VII/289) within 3"meta.ref.urlcharSpInteractive spectrum from SDSS-DR14meta.codecharNEDNED column added by the CDSmeta.ref.urlchar_RAPosition from SDSS-DR14 (right ascension part)degpos.eq.ra;meta.mainindexed_DEPosition from SDSS-DR14 (declination part)degpos.eq.dec;meta.mainindexed