J/A+A/561/A12ivo://CDS.VizieR/J/A+A/561/A12doi:10.26093/cds/vizier.35610012CDSBik A.Stolte A.Gennaro M.Brandner W.Gouliermis D.Hussmann B.,Tognelli E.Rochau B.Henning T.Adamo A.Beuther H.Pasquali A.,Wang Y.2014-06-22T16:05:32Z2013-12-17T12:02:16ZCDS support team

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

cds-question@unistra.frinfrared-sourcespre-main-sequence-starsinfrared-photometryccd-photometryEmbedded clusters like W3 Main are complex and dynamically evolving systems that represent an important phase in the star formation process. We aim to characterize of the entire stellar content of W3 Main in a statistical sense, which will then identify possible differences in evolutionary phase of the stellar populations and find clues about the formation mechanism of this massive embedded cluster. Deep JHKs imaging is used to derive the disk fraction, Ks-band luminosity functions, and mass functions for several subregions in W3 Main. A two-dimensional completeness analysis using artificial star experiments is applied as a crucial ingredient for assessing realistic completeness limits for our photometry. We find an overall disk fraction of 7.7+/-2.3%, radially varying from 9.4+/-3.0 in the central 1pc to 5.6+/-2.2% in the outer parts of W3 Main. The mass functions derived for three subregions are consistent with a Kroupa and Chabrier mass function. The mass function of IRSN3 is complete down to 0.14M_{sun}_ and shows a break at M~0.5M_{sun}_. We interpret the higher disk fraction in the center as evidence that the cluster center is younger. We find that the evolutionary sequence observed in the low-mass stellar population is consistent with the observed age spread among the massive stars. An analysis of the mass function variations does not show evidence of mass segregation. W3 Main is currently still actively forming stars, showing that the ionizing feedback of OB stars is confined to small areas (~0.5pc). The FUV feedback might be influencing large regions of the cluster as suggested by the low overall disk fraction.2014A&A...561A..12Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/561/A12CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+AS/124/205 : W3 star-forming region 345 GHz survey (Helmich+ 1997)J/AJ/129/393 : UBV photometry in W3 (Oey+, 2005)J/ApJ/654/338 : Spitzer photometry in W3 molecular cloud (Ruch+, 2007)J/MNRAS/379/663 : 850um observations of W3 giant molecular cloud (Moore+, 2007)J/ApJ/743/39 : Spitzer obs. of W3 molecular cloud (Rivera-Ingraham+, 2011)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/561/A12https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/561/A12http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/561/A12https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/561/A12https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/561/A12http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/561/A12GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/561/A12/jhk (JHKs matched photometry and photometric completeness)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/561/A12/jhk?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/561/A12/jhk?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/561/A12/jhk?GETtext/xml+votable180.050000true36.36708362.0944440.005555555555555556Cone search capability for table J/A+A/561/A12/hk (HKs matched photometry and photometric completeness)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/561/A12/hk?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/561/A12/hk?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/561/A12/hk?GETtext/xml+votable180.050000true36.36708362.0944440.005555555555555556Cone search capability for table J/A+A/561/A12/k (Ks photometry and photometric completeness)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/561/A12/k?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/561/A12/k?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/561/A12/k?GETtext/xml+votable180.050000true36.36708362.0944440.0055555555555555566/36498.650015785639275e-20 1.7003137259100215e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/561/A12?format=asciiInfrareddefaultJ/A+A/561/A12/jhkJHKs matched photometry and photometric completenessKsmagKs-band magnitudemagphot.mag;em.IR.KfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000.0)pos.eq.ra;meta.mainDEJ2000Declination (J2000.0)pos.eq.dec;meta.mainJmagJ-band magnitudemagphot.mag;em.IR.Jfloate_JmagJ-band magnitude errormagstat.error;phot.mag;em.IR.JfloatJcmpl[0/1.02] J-band completenessmeta.notefloatHmagH-band magnitudemagphot.mag;em.IR.Hfloate_HmagH-band magnitude errormagstat.error;phot.mag;em.IR.HfloatHcmpl[0/1.02] H-band completenessmeta.notefloate_KsmagKs-band magnitude errormagstat.error;phot.mag;em.IR.KfloatKscmpl[0/1.02] Ks-band completenessmeta.notefloat2MDisplay the 2MASS data (Cutri et al. 2003, Cat. II/246)meta.ref.urlcharJ/A+A/561/A12/hkHKs matched photometry and photometric completenessrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000.0)pos.eq.ra;meta.mainDEJ2000Declination (J2000.0)pos.eq.dec;meta.mainHmagH-band magnitudemagphot.mag;em.IR.Hfloate_HmagH-band magnitude errormagstat.error;phot.mag;em.IR.HfloatHcmpl[0/1.02] H-band completenessmeta.notefloatKsmagKs-band magnitudemagphot.mag;em.IR.Kfloate_KsmagKs-band magnitude errormagstat.error;phot.mag;em.IR.KfloatKscmpl[0/1.02] Ks-band completenessmeta.notefloat2MDisplay the 2MASS data (Cutri et al. 2003, Cat. II/246)meta.ref.urlcharJ/A+A/561/A12/kKs photometry and photometric completenessrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000.0)pos.eq.ra;meta.mainDEJ2000Declination (J2000.0)pos.eq.dec;meta.mainKsmagKs-band magnitudemagphot.mag;em.IR.Kfloate_KsmagKs-band magnitude errormagstat.error;phot.mag;em.IR.KfloatKscmpl[0/1.02] Ks-band completenessmeta.notefloat2MDisplay the 2MASS data (Cutri et al. 2003, Cat. II/246)meta.ref.urlchar