J/MNRAS/537/1763ivo://CDS.VizieR/J/MNRAS/537/1763doi:10.26093/cds/vizier.75371763CDSRuiz Diaz M.A.Aidelman Y.J.Baume G.Granada A.2025-03-03T20:14:41Z2025-02-12T14:48:12ZCDS support team

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

cds-question@unistra.fropen-star-clustersbe-starsphotometryvisible-astronomyline-intensitiesThis study focuses on the open cluster NGC 6834. Despite being well-known, its primary parameters show considerable variation. As an intermediate-age cluster (50-80 million years), it is expected to host a prominent population of B-type stars, including numerous Be stars. Fifteen B-type variable stars have already been identified in the vicinity of the cluster, with four confirmed as Be stars through spectroscopic observations. Our spectrophotometric analysis aims to better understand the general and specific properties of NGC 6834, with particular emphasis on its B-type stars. Photometric data were gathered from gri images obtained with the Gemini North telescope, which was completed with several photometric catalogs. Additionally, 109 optical spectra for 89 stars in the cluster's region were obtained using the GMOS-MOS spectrograph. From the photometric data, we derive the foreground cluster color excess, E(B-V)=0.62. Through photometric diagrams, including traditional color-color and color-magnitude diagrams and those incorporating the reddening-free $Q$ parameter, we identify new stars with $H\alpha$ emission. Spectral classification of 89 stars is achieved, along with estimations of basic physical parameters, and projected rotational velocities for 64 B-type stars. We identify five new Be stars: NGC 6834 3, 9, and 118 as cluster members, and NGC 6834 23 and 121 as non-members. The research contributes to a deeper understanding of the structure of NGC 6834 and its B-type star population.2025MNRAS.537.1763Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/537/1763CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/537/1763https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/537/1763http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/537/1763https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/537/1763https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/537/1763http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/537/1763GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/537/1763/table2 (Photometric data)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/537/1763/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/537/1763/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/537/1763/table2?GETtext/xml+votable180.050000true298.049034892229.22070961190.005555555555555556Cone search capability for table J/MNRAS/537/1763/table4 (Spectral classification and fundamental parameters for stars with GMOS spectroscopic observations)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/537/1763/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/537/1763/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/537/1763/table4?GETtext/xml+votable180.050000true298.05662529.40766670.005555555555555556Cone search capability for table J/MNRAS/537/1763/table5 (Extinction and absorption values for stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/537/1763/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/537/1763/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/537/1763/table5?GETtext/xml+votable180.050000true298.0519006454329.406907659840.005555555555555556Cone search capability for table J/MNRAS/537/1763/table9 (EW and FWHM measured values for MgII4481{AA} and HeIi5875{AA}, and derived vsini values)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/537/1763/table9?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/537/1763/table9?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/537/1763/table9?GETtext/xml+votable180.050000true298.0519006454329.406907659840.0055555555555555566/144155.132623062891072e-19 6.118840631666147e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/537/1763?format=asciiOpticaldefaultJ/MNRAS/537/1763/table2Photometric datae_imag? Error in i magnitudemagstat.error;phot.magdoublenullableHamag? Halpha magnitudemagphot.flux;em.line.Halphadoublenullablee_Hamag? Error in Halpha magnitudemagstat.error;phot.magdoublenullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainindexedDEJ2000Declination (J2000)degpos.eq.dec;meta.mainindexedName2MASS identifier (if available) JHHMMSS.ss+DDMMSS.smeta.id;meta.maincharSourceIDIGAPS identifier (if available) NNNNNN-N-NNNNNmeta.idcharSourceSource catalog of the gri magnitudesmeta.bibcharUmag? U magnitudemagphot.mag;em.opt.Udoublenullablee_Umag? Error in U magnitudemagstat.error;phot.magdoublenullablegmag? g magnitudemagphot.mag;em.opt.Bdoublenullablee_gmag? Error in g magnitudemagstat.error;phot.magdoublenullablermag? r magnitudemagphot.mag;em.opt.Rdoublenullablee_rmag? Error in r magnitudemagstat.error;phot.magdoublenullableimag? i magnitudemagphot.mag;em.opt.IdoublenullableJ/MNRAS/537/1763/table4Spectral classification and fundamental parameters for stars with GMOS spectroscopic observations2MASS2MASS identification, HHMMSSss+DDMMSSsmeta.idcharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNGC6834? Funfschilling (1967ZA.....66..440F) identification, NGC 6834 NNN in Simbadmeta.id;meta.mainintnullableDEJ2000Declination (J2000)pos.eq.dec;meta.maingmagg magnitudemagphot.mag;em.opt.BfloatSpTypeMK spectral typesrc.spTypecharTeff? Effective temperatureKphys.temperature.effectiveintnullablee_Teff? Error in effective temperatureKstat.error;phys.temperature.effectiveintnullablelogg? Surface gravitylog(Sun)phys.gravityfloatnullablee_logg? Error in surface gravitylog(Sun)stat.errorfloatnullableVMAG? Absolute visual magnitudemagphys.magAbsfloatnullableBC? Bolometric correctionmagphot.mag.bcfloatnullable(B-V)0? Intrinsic color indexmagphot.color;em.opt.B;em.opt.VfloatnullableMember[m nm] Membership to the cluster, m = member, nm = not membermeta.code.membercharJ/MNRAS/537/1763/table5Extinction and absorption values for starsHaMAGAbsolute Halpha magnitudemagphys.magAbsfloatAHaExtinction in Halpha bandmagphys.absorptionfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDFunfschilling (1967ZA.....66..440F) identification, NGC 6834 NNN or 2MASS idmeta.id;meta.mainchar2MASS2MASS identification, HHMMSSss+DDMMSSsmeta.idchargMAGAbsolute g magnitudemagphys.magAbsfloatAgExtinction in g bandmagphys.absorptionfloatrMAGAbsolute r magnitudemagphys.magAbsfloatArExtinction in r bandmagphys.absorptionfloatiMAGAbsolute i magnitudemagphys.magAbsfloatAiExtinction in i bandmagphys.absorptionfloatE(g-r)Excess in (g-r) colourmagphot.color.excessfloatE(r-Ha)Excess in (r-Ha) colourmagphot.color.excessfloatE(r-i)Excess in (r-i) colourmagphot.color.excessfloatRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainJ/MNRAS/537/1763/table9EW and FWHM measured values for MgII4481{AA} and HeIi5875{AA}, and derived vsini valuesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNGC6834? Funfschilling (1967ZA.....66..440F) identification, NGC 6834 NNN in Simbadmeta.id;meta.mainintnullable2MASS2MASS ID, HHMMSSss+DDMMSSsmeta.idcharEW4471? HeI 4471{AA} equivalent width0.1nmspect.line.eqWidthfloatnullablee_EW4471? Error in HeI 4471{AA} equivalent width0.1nmstat.errorfloatnullableFWHM4471? HeI 4471{AA} FWHM0.1nmspect.line.widthfloatnullablee_FWHM4471? Error in HeI 4471{AA} FWHM0.1nmstat.errorfloatnullableEW4481? MgII 4481{AA} equivalent width0.1nmspect.line.eqWidthfloatnullablee_EW4481? Error in MgII 4481{AA} equivalent width0.1nmstat.errorfloatnullableFWHM4481? MgII 4481{AA} FWHM0.1nmspect.line.widthfloatnullablee_FWHM4481? Error in MgII 4481{AA} FWHM0.1nmstat.errorfloatnullableEW5875? HeI 5875{AA} equivalent width0.1nmspect.line.eqWidthfloatnullablee_EW5875? Error in HeI 5875{AA} equivalent width0.1nmstat.errorfloatnullableFWHM5875? HeI 5875{AA} FWHM0.1nmspect.line.widthfloatnullablee_FWHM5875? Error in HeI 5875{AA} FWHM0.1nmstat.errorfloatnullableEW6678? HeI 6678{AA} equivalent width0.1nmspect.line.eqWidthfloatnullablee_EW6678? Error in HeI 6678{AA} equivalent width0.1nmstat.errorfloatnullableFWHM6678? HeI 6678{AA} FWHM0.1nmspect.line.widthfloatnullablee_FWHM6678? Error in HeI 6678{AA} FWHM0.1nmstat.errorfloatnullablevsini? Rotational velocity vsini derivedkm/sphys.veloc.rotatintnullablee_vsini? Error in vsini derivedkm/sstat.error;phys.veloc.rotatintnullableRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.main