J/AJ/124/3042ivo://CDS.VizieR/J/AJ/124/3042doi:10.26093/cds/vizier.51243042CDSWilliams R.J.Pogge R.W.Mathur S.2023-04-06T16:50:52Z2003-03-29T07:10:41ZCDS support team

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

cds-question@unistra.frseyfert-galaxiesradio-sourcesWe present a sample of 150 narrow-line Seyfert 1 galaxies (NLS1's) found within the Sloan Digital Sky Survey (SDSS) Early Data Release (EDR) (Stoughton et al., 2002AJ....123..485S), only two of which were previously identified as such. This substantially increases the known number of NLS1's and provides a basic method by which to identify many more with subsequent releases of SDSS data. With its large size and homogeneous, well-defined selection criteria, this sample will help alleviate two major problems that have plagued NLS1 research in the past; namely, their relative rarity and significant differences in selection algorithms between the known samples. Forty-five of these SDSS-selected NLS1's are detected at energies of 0.1-2keV in the ROSAT All-Sky Survey (RASS) and are found to have ultrasoft X-ray spectra with photon indices of {Gamma}>~2, in agreement with previous results for NLS1's. However, about 10-20 of those NLS1's that were not detected by ROSAT have optical properties very similar to the detected objects and so should also have been detected by the RASS. This may be due to either significant intrinsic absorption in many NLS1's, or a significant subclass of NLS1's that have uncharacteristic, intrinsically flatter (hence harder) X-ray spectral energy distributions.2002AJ....124.3042Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/124/3042CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/224 : Quasars and Active Galactic Nuclei (10th Ed.) (Veron+ 2001)IX/10 : ROSAT All-Sky Survey Bright Source Catalogue (Vosges+, 1999)IX/29 : ROSAT All-Sky Survey Faint Source Catalog (Voges+ 2000)J/AJ/123/567 : SDSS quasar catalog (Schneider+, 2002)J/AJ/123/485 : SDSS: early data release (EDR) (Stoughton+, 2002)http://archive.stsci.edu/sdss/edr_main.html : SDSS-EDR Home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/124/3042https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/124/3042http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/124/3042https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/124/3042https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/124/3042http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/124/3042GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/124/3042/table1 (NLS1s from the SDSS Early Data Release)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/124/3042/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/124/3042/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/124/3042/table1?GETtext/xml+votable180.050000true0.2880833-0.68930560.0055555555555555565/4457 5797 6741 6/0 10074-10075 10085 10094 10181-10182 10185 10190 10192 10214 10232 11587 11590 11593 11595 11617 17407 17746 17751 17754 17761 17766-17768 17770 17773 17778 17818 17820 17825-17826 17832 17834 17838 17840 17982 18002 18006 18009 18020 18028-18029 18061 18063 18066-18067 18069-18070 18073 18075 18089 18093 18770 18776 18778 18790-18791 18796 18800-18801 23103 23198 23201 23204 23206 23209 23211 23216-23217 23232 25855 25917 25919 25935 25939-25940 25942 25948 25956 25958 25961 26011 26018 26175 26191 26198 26203 26209-26210 26221 26224 26255 26277 26285 26879 26977 26981 27028 27032-27033 27041 27043 27046 27048 27050 27053 27072 27220 27224 27229 27236 27243 27245 27648 27650 31379 31383 31397-31398 31403https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/124/3042?format=asciiRadiodefaultJ/AJ/124/3042/table1NLS1s from the SDSS Early Data ReleasezRedshiftsrc.redshiftfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSDSSThe Sloan Digital Sky Survey Name (1)meta.idcharFWHMThe H{beta} Full-Width at Half-Maximumkm/sspect.line.width;em.line.HbetaintHR1? The ROSAT Hardness Ratio 1 parameter (2)phot.flux;arith.ratiofloatnullablee_HR1? Uncertainty in HR1stat.errorfloatnullableGamma? The X-ray photon index (3)spect.indexfloatnullablee_Gamma? Uncertainty in Gammastat.errorfloatnullableNote[1/5]? Additional notes (4)meta.noteintnullable_RAPosition (derived from SDSS name) (right ascension part)degpos.eq.ra;meta.main_DEPosition (derived from SDSS name) (declination part)degpos.eq.dec;meta.main