J/ApJ/452/210ivo://CDS.VizieR/J/ApJ/452/210doi:10.26093/cds/vizier.14520210CDSOey M.S.Massey P.2017-09-20T05:13:41Z2006-05-27T23:19:47ZCDS support team

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

cds-question@unistra.frmagellanic-cloudsstellar-associationsvisible-astronomybroad-band-photometryWe examine the stellar population of an OB association, LH 47/48, which is associated with a superbubble H II region, DEM 152 in the N44 nebular complex of the Large Magellanic Cloud. With CCD photometry and spectroscopy of the massive stars, we find no evidence that an unusual stellar population gave rise to the shell morphology of the gas. The slope of the initial mass function, {Gamma}=1.3+/-0.2, is consistent with that of other OB associations in the LMC, and there is no significant difference in the initial mass function internal or external to the supershell. The inferred stellar ionizing flux is consistent with the observed nebular H alpha flux. We do find evidence for triggered star formation: the H-R diagram suggests an age of >10Myr for the population interior to the bubble with more recent, <5Myr, star formation on the exterior. Using the detailed data on the stellar population, we compare a numerical form of the Weaver et al. (1977ApJ...218..377W) evolutionary model for wind-driven bubbles with the observed shell kinematics. We find a substantial discrepancy: the observed shell radius is too small and/or expansion velocity too large to be explained with this version of the model. We discuss possible explanations for the inconsistency.1995ApJ...452..210Ohttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/452/210CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/452/210https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/452/210http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/452/210https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/452/210https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/452/210http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/452/210GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/452/210/table1a (Photometry of stars in LH 47)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/452/210/table1a?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/452/210/table1a?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/452/210/table1a?GETtext/xml+votable180.050000true80.4229603-67.94566280.005555555555555556Cone search capability for table J/ApJ/452/210/table1b (photometry of stars in LH 48)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/452/210/table1b?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/452/210/table1b?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/452/210/table1b?GETtext/xml+votable180.050000true80.4768411-67.904660.005555555555555556Cone search capability for table J/ApJ/452/210/table2 (Derived parameter stars with spectral types)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/452/210/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/452/210/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/452/210/table2?GETtext/xml+votable180.050000true80.4917083-67.94036110.0055555555555555566/33102https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/452/210?format=asciiOpticaldefaultJ/ApJ/452/210/table1aPhotometry of stars in LH 47recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmSimbad column added by the CDSmeta.notecharStarStar number ([OM95] LH 47/48 NNN in Simbad)meta.id;meta.mainintm_StarMultiplicity index on Starmeta.code.multipcharXposX positionpixpos.cartesian.x;instr.detfloatYposY positionpixpos.cartesian.y;instr.detfloatVmagV magnitudemagphot.mag;em.opt.VfloatB-VB-V colour indexmagphot.color;em.opt.B;em.opt.VfloatU-BU-B colour indexmagphot.color;em.opt.U;em.opt.Bfloat_RAPosition computed from a comparison with catalog I/289 ({sigma}=0.1'') (right ascension part)degpos.eq.ra;meta.main_DEPosition computed from a comparison with catalog I/289 ({sigma}=0.1'') (declination part)degpos.eq.dec;meta.mainJ/ApJ/452/210/table1bphotometry of stars in LH 48recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmSimbad column added by the CDSmeta.notecharStarStar number ([OM95] LH 47/48 NNN in Simbad)meta.id;meta.mainintm_StarMultiplicity index on Starmeta.code.multipcharXposX positionpixpos.cartesian.x;instr.detfloatYposY positionpixpos.cartesian.y;instr.detfloatVmagV magnitudemagphot.mag;em.opt.VfloatB-VB-V colour indexmagphot.color;em.opt.B;em.opt.VfloatU-BU-B colour indexmagphot.color;em.opt.U;em.opt.Bfloat_RAPosition computed from a comparison with catalog I/289 ({sigma}=0.1'') (right ascension part)degpos.eq.ra;meta.main_DEPosition computed from a comparison with catalog I/289 ({sigma}=0.1'') (declination part)degpos.eq.dec;meta.mainJ/ApJ/452/210/table2Derived parameter stars with spectral typesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintStarStar designation (47-NNN or 48-NNN)meta.id;meta.maincharXposX positionpixpos.cartesian.x;instr.detfloatYposY positionpixpos.cartesian.y;instr.detfloatRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainVmagV magnitudemagphot.mag;em.opt.VfloatB-VB-V colour indexmagphot.color;em.opt.B;em.opt.VfloatU-BU-B colour indexmagphot.color;em.opt.U;em.opt.BfloatQReddening-free parameter (Q=(U-B)-0.72(B-V))phot.color.reddFreefloatlog(Teff)Effective temperaturelog(K)phys.temperature.effectivefloatu_log(Teff)[)] Uncertainty flag on log(Teff)meta.code.errorcharMbolBolometric magnitudemagphot.mag.bolfloatu_Mbol[)] Uncertainty flag on Mbolmeta.code.errorcharMassStar masssolMassphys.massintu_Mass[)] Uncertainty flag on Massmeta.code.error;phys.masscharSpTypeMK spectral typesrc.spTypechar