J/A+AS/139/231ivo://CDS.VizieR/J/A+AS/139/231CDSDufton P.L.Smartt S.J.Hambly N.C.2001-09-16T18:18:30Z2001-09-16T18:18:20ZCDS support team

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

cds-question@unistra.frearly-type-starsvisible-astronomyphotographic-photometryline-intensitiesWe have begun a search for early-type stars towards the galactic centre which are potentially young objects situated within the inner few kiloparsecs of the disk. U and V (or I) band photographic photometry from the UK Schmidt Telescope has been obtained to identify the bluest candidates in nineteen Schmidt fields (centred close to the galactic centre). We have spectroscopically observed these targets for three fields with the FLAIR multi-fibre system to determine their spectral types. In particular, ten early B-type stars have been identified and equivalent width measurements of their Balmer and HeI lines have been used to estimate atmospheric parameters. These early-type objects have magnitudes in the range 11.5=<V<=16.0, and our best estimates of their distance (given probable highly variable reddening in this direction together with errors in the plate photometry) suggest that some of them originated close to (i.e R_g_<3kpc), or even beyond the galactic centre. Future high-resolution spectroscopy of these stars will provide reliable atmospheric parameters and element abundances, in order to map the current chemical composition of the inner galaxy.1999A&AS..139..231Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+AS/139/231CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/373/608 : Early-type stars towards the Galactic Center (Dufton+, 2001)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+AS/139/231https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+AS/139/231http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+AS/139/231https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+AS/139/231https://vizier.iucaa.in/viz-bin/votable?-source=J/A+AS/139/231http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+AS/139/231GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+AS/139/231/table2 (Blue stellar candidates for which spectroscopy was not obtained)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+AS/139/231/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+AS/139/231/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+AS/139/231/table2?GETtext/xml+votable180.050000true262.529125-33.69458330.005555555555555556Cone search capability for table J/A+AS/139/231/table3 (*Field 393 preliminary identifications of targets)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+AS/139/231/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/A+AS/139/231/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+AS/139/231/table3?GETtext/xml+votable180.050000true264.2483333-36.94461110.005555555555555556Cone search capability for table J/A+AS/139/231/table4 (Field 454 preliminary identifications of targets)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+AS/139/231/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/A+AS/139/231/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+AS/139/231/table4?GETtext/xml+votable180.050000true261.7551667-29.35880560.005555555555555556Cone search capability for table J/A+AS/139/231/table5 (Field 456 preliminary identifications of targets)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+AS/139/231/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/A+AS/139/231/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+AS/139/231/table5?GETtext/xml+votable180.050000true273.4797917-29.08494440.0055555555555555565/7179 7192 7194-7195 7201 7208 10709 6/28707 28710 28713-28715 28725 28731-28733 28772 28774-28775 28801 28803 28808-28809 28820 28838 28840-28842 28844-28845 28847 28864-28866 28868 28872 29185-29188 29192 42366-42367 42452-42454 42487 42491-42493 42495 42845https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+AS/139/231?format=asciiOpticaldefaultJ/A+AS/139/231/table6*Equivalent widths for early-type candidatesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintType[EML] Star type (1)src.classcharFieldField numberobs.fieldintStarStar number in the fieldmeta.id;meta.mainintMeanMean stellar counttime.epochintEW3970? Balmer (3970{AA}) equivalent width0.1nmspect.line.eqWidthfloatnullableu_EW3970Marginal measurementmeta.code.errorcharEW4101? H{epsilon} (4101{AA}) equivalent width0.1nmspect.line.eqWidthfloatnullableu_EW4101Marginal measurementmeta.code.errorcharn_EW4101Note on the presence of line EW4101 (2)meta.notecharEW4340H{delta} (4340{AA}) equivalent width0.1nmspect.line.eqWidthfloatu_EW4340Marginal measurementmeta.code.errorcharEW4026? H{gamma} (4026{AA}) equivalent width0.1nmspect.line.eqWidthfloatnullableu_EW4026Marginal measurementmeta.code.errorcharn_EW4026Note on the presence of line EW4026 (2)meta.notecharEW4143? He I (4143{AA}) equivalent width0.1nmspect.line.eqWidthfloatnullableu_EW4143Marginal measurementmeta.code.errorcharn_EW4143Note on the presence of line EW4143 (2)meta.notecharEW4387? He I (4387{AA}) equivalent width0.1nmspect.line.eqWidthfloatnullableu_EW4387Marginal measurementmeta.code.errorcharn_EW4387Note on the presence of line EW4387 (2)meta.notecharEW4471? He I (4471{AA}) equivalent width0.1nmspect.line.eqWidthfloatnullableu_EW4471Marginal measurementmeta.code.errorcharEW4481? MgII (4481{AA}) equivalent width0.1nmspect.line.eqWidthfloatnullableu_EW4481Marginal measurementmeta.code.errorcharn_EW4481Note on the presence of line EW4481 (2)meta.notecharEW3933? Ca II (3933{AA}) equivalent width0.1nmspect.line.eqWidthfloatnullableu_EW3933Marginal measurementmeta.code.errorcharn_EW3933Note on the presence of line EW3933 (2)meta.notecharl_Teff[<>= ] Limit flag on Teffmeta.code.errorcharTeffEffective temperatureKphys.temperature.effectiveintu_TeffMarginal measurementmeta.code.errorcharl_logg[<>= ] Limit flag on loggmeta.code.errorcharloggSurface gravitylog(cm.s**-2)phys.gravityfloatu_loggMarginal measurementmeta.code.errorcharJ/A+AS/139/231/table2Blue stellar candidates for which spectroscopy was not obtainedrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintf_Star[+] when the star is also in table6meta.code.errorcharFieldField number (1)obs.fieldintStarStar number in the field (1)meta.id;meta.mainintRA2000Right ascension (2000)pos.eq.ra;meta.mainDE2000Declination (2000)pos.eq.dec;meta.mainVmagV magnitude (I for field 456)magphot.mag;em.opt.Vfloat(u-v)(u-v) colour index (u-i for field 456)magphot.color;em.opt.U;em.opt.VfloatJ/A+AS/139/231/table3*Field 393 preliminary identifications of targetsComCommentsmeta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintf_Star[+] when the star is also in table6meta.code.errorcharFieldField numberobs.fieldintStarStar number in the fieldmeta.id;meta.mainintRA2000Right ascension (2000)pos.eq.ra;meta.mainDE2000Declination (2000)pos.eq.dec;meta.mainVmagV magnitudemagphot.mag;em.opt.Vfloat(u-v)u-v colour indexmagphot.color;em.opt.U;em.opt.VfloatCountMean stellar countmeta.numberintSpTypeSpectral typesrc.spTypecharJ/A+AS/139/231/table4Field 454 preliminary identifications of targetsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintf_Star[+] when the star is also in table6meta.code.errorcharFieldField numberobs.fieldintStarStar number in the fieldmeta.id;meta.mainintRA2000Right ascension (2000)pos.eq.ra;meta.mainDE2000Declination (2000)pos.eq.dec;meta.mainVmagV magnitudemagphot.mag;em.opt.Vfloat(u-v)u-v colour indexmagphot.color;em.opt.U;em.opt.VfloatCountMean stellar countmeta.numberintComCommentsmeta.notecharSpTypeSpectral typesrc.spTypecharJ/A+AS/139/231/table5Field 456 preliminary identifications of targetsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintf_Star[+] when the star is also in table6meta.code.errorcharField[456] Field numberobs.fieldintStarStar number in the fieldmeta.id;meta.mainintRA2000Right ascension (2000)pos.eq.ra;meta.mainDE2000Declination (2000)pos.eq.dec;meta.mainImagI magnitudemagphot.mag;em.opt.Ifloatu-iu-i colour indexmagphot.color;em.opt.U;em.opt.RfloatCbMean blue (3900{AA} to 4600{AA}) stellar countphot.colorintCrMean red (5600{AA} to 6800{AA}) stellar countphot.colorintComCommentsmeta.notecharSpTypeSpectral typesrc.spTypechar