J/MNRAS/470/3765ivo://CDS.VizieR/J/MNRAS/470/3765doi:10.26093/cds/vizier.74703765CDSMassa D.Fullerton A.W.Prinja R.K.2024-08-17T20:19:54Z2020-06-13T10:21:11ZCDS support team

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

cds-question@unistra.frmagellanic-cloudso-starsvisible-astronomybroad-band-photometryeffective-temperatureWe use a combination of BVJHK and Spitzer [3.6], [5.8] and [8.0] photometry to determine infrared (IR) excesses for a sample of 58 Large Magellanic Cloud and 46 Small Magellanic Cloud O stars. This sample is ideal for determining IR excesses because the very small line-of-sight reddening minimizes uncertainties due to extinction corrections. We use the core-halo model developed by Lamers & Waters to translate the excesses into mass-loss rates and demonstrate that the results of this simple model agree with the more sophisticated CMFGEN models to within a factor of 2. Taken at face value, the derived mass-loss rates are larger than those predicted by Vink et al. (2001A&A...369..574V), and the magnitude of the disagreement increases with decreasing luminosity. However, the IR excesses need not imply large mass-loss rates. Instead, we argue that they probably indicate that the outer atmospheres of O stars contain complex structures and that their winds are launched with much smaller velocity gradients than normally assumed. If this is the case, it could affect the theoretical and observational interpretations of the 'weak wind' problem, where classical mass-loss indicators suggest that the mass-loss rates of lower luminosity O stars are far less than expected.2017MNRAS.470.3765Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/470/3765CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/PASP/121/634 : FUSE observations in Magellanic Clouds (Blair+, 2009)J/AJ/138/1003 : IR photometry of massive LMC stars (Bonanos+, 2009)J/AJ/140/416 : IR photometry of massive stars in the SMC (Bonanos+, 2010)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/470/3765https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/470/3765http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/470/3765https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/470/3765https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/470/3765http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/470/3765GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/470/3765/table13 (SMC stellar (table1) and wind (table3) properties)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/470/3765/table13?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/470/3765/table13?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/470/3765/table13?GETtext/xml+votable180.050000true11.6359583-73.10158330.005555555555555556Cone search capability for table J/MNRAS/470/3765/table24 (LMC stellar (table1) and wind (table3) properties)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/470/3765/table24?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/470/3765/table24?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/470/3765/table24?GETtext/xml+votable180.050000true84.2724444-66.35973220.0055555555555555565/8274 6/33047 33052-33053 33055 33076-33077 33092 33094-33095 33100-33101 33103 33106-33107 33110 33112-33113 33115-33116 33120-33122 33126-33127 33294-33295 33298 33304 33306 33316-33317 333283.322582951404819e-19 3.852589004194616e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/470/3765?format=asciiOpticaldefaultJ/MNRAS/470/3765/table13SMC stellar (table1) and wind (table3) propertiesSimbadNameSimbad column added by the CDSmeta.idcharNotesNotes on IR SED (3)meta.notecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharSpTypeSpectral Typesrc.spTypecharr_SpTypeSource for spectral type (1)meta.ref;pos.framecharVmagV band magnitudemagphot.mag;em.opt.VfloatB-V(B-V) colour indexmagphot.color;em.opt.B;em.opt.VfloatTeffEffective temperatureKphys.temperature.effectiveintlogLLog of luminositylog(solLum)phys.luminosityfloatMassStellar masssolMassphys.massfloatRadiusStellar radiussolRadphys.angSize;srcfloatVinfWind terminal velocitykm/sphys.velocintr_VinfReference for terminal velocity (1)meta.ref;pos.framechardM/dtThTheoretical mass loss rate (2)solMass/yrphys.mass.lossfloatdM/dtIRMass loss rate determined from SED fitsolMass/yrphys.mass.lossfloate_dM/dtThe 1(sigma) error in Mdot_IRsolMass/yrstat.errorfloatE(B-V)Reddening determined from SED fitmagphot.color.excessfloate_E(B-V)The 1{sigma} uncertainty in E(B-V)magstat.errorfloatE(B-V)0Reddening determined from Spectral typemagphot.color.excessfloatchi2Reduced chi squared of SED fitstat.fit.chi2;stat.fit.param;meta.modelledfloat_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/MNRAS/470/3765/table24LMC stellar (table1) and wind (table3) propertiesSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharSpTypeSpectral Typesrc.spTypecharr_SpTypeSource for spectral type (1)meta.ref;pos.framecharVmagV band magnitudemagphot.mag;em.opt.VfloatB-V(B-V) colour indexmagphot.color;em.opt.B;em.opt.VfloatTeffEffective temperatureKphys.temperature.effectiveintlogLLog of luminositylog(solLum)phys.luminosityfloatMassStellar masssolMassphys.massfloatRadiusStellar radiussolRadphys.angSize;srcfloatVinfWind terminal velocitykm/sphys.velocintr_VinfReference for terminal velocity (1)meta.ref;pos.framechardM/dtThTheoretical mass loss rate (2)solMass/yrphys.mass.lossfloatdM/dtIRMass loss rate determined from SED fitsolMass/yrphys.mass.lossfloate_dM/dtThe 1(sigma) error in Mdot_IRsolMass/yrstat.errorfloatE(B-V)Reddening determined from SED fitmagphot.color.excessfloate_E(B-V)The 1{sigma} uncertainty in E(B-V)magstat.errorfloatE(B-V)0Reddening determined from Spectral typemagphot.color.excessfloatchi2Reduced chi squared of SED fitstat.fit.chi2;stat.fit.param;meta.modelledfloatNotesNotes on IR SED (3)meta.notechar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main