J/A+A/397/463ivo://CDS.VizieR/J/A+A/397/463doi:10.26093/cds/vizier.33970463CDSUgryumov A.V.Engels D.Pustilnik S.A. Kniazev A.Y.Pramsky A.G.,Hagen H.-J.2003-02-16T17:28:16Z2003-02-16T18:27:01ZCDS support team

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

cds-question@unistra.frgalaxiesphotometryspectroscopyradial-velocityWe present the description and the first results of a new project devoted to the search for extremely metal-deficient blue compact/HII-galaxies (BCGs) and to the creation of a well selected large BCG sample with strong emission lines. Such galaxies should be suitable for reliable determination of their oxygen abundance through the measurement of the faint [OIII]4363{AA} line. The goals of the project are two-fold: a) to discover a significant number of new extremely metal-poor galaxies (Z<=1/20Z_{sun}_), and b) to study the metallicity distribution of local BCGs. Selection of candidates for follow-up slit spectroscopy is performed on the database of objective prism spectra of the Hamburg Quasar Survey. The sky region is limited by {delta}>=0{deg} and b^II^<=-30{deg}. In this paper we present the results of the follow-up spectroscopy conducted with the Russian 6m telescope. The list of observed candidates contained 52 objects, of which 46 were confirmed as strong-lined BCGs (EW([OIII]5007>=100{AA}). The remaining five lower excitation ELGs include three BCGs, and two galaxies classified as SBN (Starburst Nucleus) and DANS (Dwarf Amorphous Nucleus Starburst). One object is identified as a quasar with a strong Ly_alpha emission line near {lambda}=5000{AA} (z~3). We provide a list with coordinates, measured radial velocities, B-magnitudes, equivalent widths EW([OIII]5007) and EW(H{beta}) and for the 46 strong-lined BCGs the derived oxygen abundances 12+log(O/H). The abundances range between 7.42 and 8.4 (corresponding to metallicities between 1/30 and 1/3Z_{sun}_). The sample contains four galaxies with Z<=1/20Z_{sun}_, of which three are new discoveries. This demonstrates the high efficiency of the new project to find extremely metal-deficient galaxies. The radial velocities of the strong-lined ELGs range between 500 and 19000km/s with a median value of ~6400km/s. The typical B-magnitudes of the galaxies presented are 17.0mag-18.0mag.2003A&A...397..463Uhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/397/463CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+AS/135/511 : The Hamburg/SAO Survey for ELGs. I. (Ugryumov+ 1999)J/A+AS/137/299 : The Hamburg/SAO Survey for ELGs. II. (Pustilnik+ 1999)J/A+AS/142/417 : The Hamburg/SAO Survey for ELGs. III. (Hopp+, 2000)J/A+A/366/771 : The Hamburg/SAO Survey for ELGs. IV (Kniazev+, 2001)J/A+A/374/907 : The Hamburg/SAO Survey for ELGs. V. (Ugryumov+, 2001)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/397/463https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/397/463http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/397/463https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/397/463https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/397/463http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/397/463GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/397/463/table2 (Parameters of the strong-lined BCGs)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/397/463/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/397/463/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/397/463/table2?GETtext/xml+votable180.050000true5.08916711.2058330.005555555555555556Cone search capability for table J/A+A/397/463/table3 (Parameters of Emission-Line Galaxies with EW([OIII]5007)<100{AA})https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/397/463/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/397/463/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/397/463/table3?GETtext/xml+votable180.050000true1.0487517.3302780.0055555555555555566/605 684 2068 2108-2109 2153 2159 2205 2210-2211 2231 2233 2258 2312 2561 13380 18235 18422 18425 19417 19570 19695 19702-19703 19756 19793-19794 19812 19828 19858 19901 19919 19934 19951 19959 20045 20083-20084 20109 20126 20145 20149 20193 20201 20207 20211 20215 20283 20317 20374https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/397/463?format=asciiOpticaldefaultJ/A+A/397/463/table2Parameters of the strong-lined BCGsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameGalaxy namemeta.id;meta.maincharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainRVHeliocentric radial velocitykm/sphys.veloc;pos.heliocentricinte_RVError of radial velocitykm/sstat.errorintBmagMagnitude in B filter (1)magphot.mag;em.opt.BfloatABThe extinction in Galaxy in the B-band (2)magphys.absorptionfloatBMAGAbsolute B-magnitude (3)magphys.magAbs;em.optfloatEWHb? Equivalent width of H{beta} (4861{AA}) emission linenmspect.line.eqWidthfloatnullableEW5007? Equivalent width of [OIII]5007A emission linenmspect.line.eqWidthfloatnullable12+log(O/H)? The derived values of O abundance, 12+log(O/H)phys.abundfloatnullableu_12+log(O/H)Uncertainty flag on 12+log(O/H) (4)meta.code.errorcharNamesOther names from NEDmeta.idcharRef? References to other sources of spectral information (5)meta.refintnullableJ/A+A/397/463/table3Parameters of Emission-Line Galaxies with EW([OIII]5007)<100{AA}recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameGalaxy namemeta.id;meta.maincharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainRVHeliocentric radial velocitykm/sphys.veloc;pos.heliocentricinte_RVError of radial velocitykm/sstat.errorintBmagMagnitude in B filter (1)magphot.mag;em.opt.BfloatABThe extinction in Galaxy in the B-band (2)magphys.absorptionfloatBMAGAbsolute B-magnitude (3)magphys.magAbs;em.optfloatEWHb? Equivalent width of H{beta} (4861{AA}) emission linenmspect.line.eqWidthfloatnullableEW5007? Equivalent width of [OIII]5007A emission linenmspect.line.eqWidthfloatnullable12+log(O/H)? The derived values of O abundance, 12+log(O/H)phys.abundfloatnullableu_12+log(O/H)Uncertainty flag on 12+log(O/H) (4)meta.code.errorcharNamesOther names from NEDmeta.idcharRef? References to other sources of spectral information (5)meta.refintnullable