J/ApJ/786/113ivo://CDS.VizieR/J/ApJ/786/113doi:10.26093/cds/vizier.17860113CDSAllen T.S.Prchlik J.J.Megeath S.T.Gutermuth R.A.Pipher J.L.,Naylor T.Jeffries R.D.2017-07-21T10:46:48Z2017-07-04T10:54:05ZCDS support team

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

cds-question@unistra.frstellar-associationsopen-star-clustersextinctionvisible-astronomysloan-photometryinfrared-photometrystellar-spectral-typesWe determine the extinction law through Cep OB3b, a young cluster of 3000 stars undergoing gas dispersal. The extinction is measured toward 76 background K giants identified with MMT/Hectospec spectra. Color excess ratios were determined toward each of the giants using V and R photometry from the literature, g, r, i, and z photometry from the Sloan Digital Sky Survey and J, H, and K_s_ photometry from the Two Micron All Sky Survey. These color excess ratios were then used to construct the extinction law through the dusty material associated with Cep OB3b. The extinction law through Cep OB3b is intermediate between the R_V_=3.1 and R_V_=5 laws commonly used for the diffuse atomic interstellar medium and dense molecular clouds, respectively. The dependence of the extinction law on line-of-sight A_V_ is investigated and we find the extinction law becomes shallower for regions with A_V_>2.5 mag. We speculate that the intermediate dust law results from dust processing during the dispersal of the molecular cloud by the cluster.2014ApJ...786..113Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/786/113CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)J/MNRAS/341/805 : UBVI CCD photometry of Cep OB3b (Pozzo+, 2003)J/MNRAS/403/545 : Young stars in Cepheus OB3b (Littlefair+, 2010)J/ApJ/750/125 : Spitzer imaging of Cepheus OB3b cluster (Allen+, 2012)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/786/113https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/786/113http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/786/113https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/786/113https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/786/113http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/786/113GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/786/113/table1 (Sources used to determine Extinction Law)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/786/113/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/786/113/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/786/113/table1?GETtext/xml+votable180.050000true343.101208362.68777780.0055555555555555566/156831.1166583743361574e-19 4.653515163505597e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/786/113?format=asciiInfraredOpticaldefaultJ/ApJ/786/113/table1Sources used to determine Extinction LawrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIndex[1/76] Index numbermeta.idintRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of the Declination (J2000)pos.eq.dec;meta.maingmagSDSS g band magnitudemagphot.mag;em.opt.Bfloate_gmagUncertainty in gmagmagstat.error;phot.mag;em.opt.BfloatVmagLiterature V band magnitudemagphot.mag;em.opt.Vfloate_VmagUncertainty in Vmagmagstat.error;phot.mag;em.opt.VfloatrmagSDSS r band magnitudemagphot.mag;em.opt.Rfloate_rmagUncertainty in rmagmagstat.error;phot.mag;em.opt.RfloatRmagLiterature R band magnitudemagphot.mag;em.opt.Rfloate_RmagUncertainty in Rmagmagstat.error;phot.mag;em.opt.RfloatimagSDSS i band magnitudemagphot.mag;em.opt.Ifloate_imagUncertainty in imagmagstat.error;phot.mag;em.opt.IfloatzmagSDSS z band magnitudemagphot.mag;em.opt.Ifloate_zmagUncertainty in zmagmagstat.error;phot.mag;em.opt.IfloatJmag2MASS J band magnitudemagphot.mag;em.IR.Jfloate_JmagUncertainty in Jmagmagstat.error;phot.mag;em.IR.JfloatHmag2MASS H band magnitudemagphot.mag;em.IR.Hfloate_HmagUncertainty in Hmagmagstat.error;phot.mag;em.IR.HfloatKsmag2MASS K_s_ band magnitudemagphot.mag;em.IR.Kfloate_KsmagUncertainty in Ksmagmagstat.error;phot.mag;em.IR.KfloatJ-KsThe (J-K_s_) colormagphot.color;em.IR.J;em.IR.Kfloate_J-KsUncertainty in J-Ksmagstat.error;phot.color;em.IR.JfloatAVThe V band extinctionmagphys.absorption;em.opt.VfloatSpTypeSpectral Typesrc.spTypechare_SpTypeUncertainty in SpTypestat.error;src.spTypefloatLMN2010{Display the Littlefair et al. (2010, Cat. J/MNRAS/403/545) data within 3"}meta.ref.urlintnullable