J/A+A/650/A156ivo://CDS.VizieR/J/A+A/650/A156doi:10.26093/cds/vizier.36500156CDSde la Fuente D.Roman-Zuniga C.G.Jimenez-Bailon E.Alves J.Garcia M.,Venus S.2021-07-05T13:07:08Z2021-06-24T06:58:44ZCDS support team

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

cds-question@unistra.fropen-star-clustersinfrared-sourcesx-ray-sourcesinfrared-photometryvisible-astronomystellar-distanceproper-motionstrigonometric-parallaxDisentangling line-of-sight alignments of young stellar populations is crucial for observational studies of star-forming complexes. This task is particularly problematic in a Cygnus-X subregion where several components, located at different distances, overlap: the Berkeley 87 young massive cluster, the poorly known [DB2001] Cl05 embedded cluster, and the ON2 star-forming complex, which in turn is composed of several HII regions. We provide a methodology for building an exhaustive census of young objects that can consistently treat large differences in extinction and distance. OMEGA2000 near-infrared observations of the Berkeley 87 / ON2 field were merged with archival data from Gaia, Chandra, Spitzer, and Herschel, and with cross-identifications from the literature. To address the incompleteness effects and selection biases that arise from the line-of-sight overlap, we adapted existing methods for extinction estimation and young object classification. We also defined the intrinsic reddening index, R_int_, a new tool for separating intrinsically red sources from those whose infrared color excess is caused by extinction. Finally, we introduce a new method for finding young stellar objects based on R_int_. We find 571 objects whose classification is related to recent or ongoing star formation. Together with other point sources with individual estimates of distance or extinction, we compile a catalog of 3005 objects to be used for further membership work. A new distance for Berkeley 87, (1673+/-17)pc, is estimated as a median of 13 spectroscopic members with accurate Gaia EDR3 parallaxes. The flexibility of our approach, especially regarding the R_int_ definition, allows overcoming photometric biases caused by large variations in extinction and distance, in order to obtain homogeneous catalogs of young sources. The multiwavelength census that results from applying our methods to the Berkeley 87 / ON2 field will serve as a basis for disentangling the overlapped populations.2021A&A...650A.156Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/650/A156CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/350 : Gaia EDR3 (Gaia Collaboration, 2020)I/352 : Distances to 1.47 billion stars in Gaia EDR3 (Bailer-Jones+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/650/A156https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/650/A156http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/650/A156https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/650/A156https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/650/A156http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/650/A156GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/650/A156/table2 (Catalog of sources with extinction, distance, or object classification results)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/650/A156/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/650/A156/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/650/A156/table2?GETtext/xml+votable180.050000true305.313916737.40858330.005555555555555556Cone search capability for table J/A+A/650/A156/tablec1 (Astrometry and photometry for sources in table2.dat)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/650/A156/tablec1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/650/A156/tablec1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/650/A156/tablec1?GETtext/xml+votable180.050000true305.313916737.40858330.0055555555555555566/14622 146447.952274030004205e-20 1.7798557115773645e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/650/A156?format=asciiX-rayOpticalInfrareddefaultJ/A+A/650/A156/table2Catalog of sources with extinction, distance, or object classification resultsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/3005] Source numbermeta.id;meta.mainintRAJ2000Right ascension (J2000.0)pos.eq.ra;meta.mainDEJ2000Declination (J2000.0)pos.eq.dec;meta.mainIDLiterature identifier (1)meta.idcharKmag? K-band magnitudemagphot.mag;em.IR.KfloatnullabledetsMatched observations (2)meta.codecharPopClassification based on reddening level (3)meta.codecharCl05reg[in out] Inside or outside the Cl05 region?meta.notecharRint? Intrinsic reddening indexphot.color.reddFreefloatnullableAV? V-band extinctionmagphys.absorptionfloatnullablen_AV[R] Note on AV (4)meta.notecharrest? Distance estimatekpcpos.distancefloatnullablee_rest? Lower error for distance estimate (5)kpcstat.error;stat.minfloatnullableE_rest? Upper error for distance estimate (6)kpcstat.error;stat.maxfloatnullableTypeSource classification (7)meta.code.classcharJ/A+A/650/A156/tablec1Astrometry and photometry for sources in table2.datSeq[1/3005] Source numbermeta.id;meta.mainintrecnoRecord 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.mainPlx? Parallaxmaspos.parallaxfloatnullablee_Plx? Parallax errormasstat.error;pos.parallaxfloatnullablePlxcor? Bias-corrected parallaxmaspos.parallax.trigfloatnullablepmRA? Proper motion in right ascensionmas/yrpos.pm;pos.eq.rafloatnullablee_pmRA? Error for proper motion in right ascensionmas/yrstat.error;pos.pm;pos.eq.rafloatnullablepmDE? Proper motion in declinationmas/yrpos.pm;pos.eq.decfloatnullablee_pmDE? Error for proper motion in declinationmas/yrstat.error;pos.pm;pos.eq.decfloatnullableX-IR? Angular separation between the X-ray source and its infrared counterpartarcsecpos.angDistancefloatnullableXsep? Angular separation between the 2009 and 2016 Chandra detectionsarcsecpos.angDistancefloatnullableJmag? J-band magnitudemagphot.mag;em.IR.Jfloatnullablee_Jmag? Error for J-band magnitudemagstat.error;phot.magfloatnullableHmag? H-band magnitudemagphot.mag;em.IR.Hfloatnullablee_Hmag? Error for H-band magnitudemagstat.error;phot.magfloatnullableKmag? K-band magnitudemagphot.mag;em.IR.Kfloatnullablee_Kmag? Error for K-band magnitudemagstat.error;phot.magfloatnullableI1mag? IRAC [3.6] magnitudemagphot.mag;em.IR.3-4umfloatnullablee_I1mag? IRAC [3.6] magnitude errormagstat.error;phot.magfloatnullableI2mag? IRAC [4.5] magnitudemagphot.mag;em.IR.4-8umfloatnullablee_I2mag? IRAC [4.5] magnitude errormagstat.error;phot.magfloatnullableI3mag? IRAC [5.8] magnitudemagphot.flux.density;em.IR.4-8umfloatnullablee_I3mag? IRAC [5.8] magnitude errormagstat.error;phot.magfloatnullableI4mag? IRAC [8.0] magnitudemagphot.flux.density;em.IR.8-15umfloatnullablee_I4mag? IRAC [8.0] magnitude errormagstat.error;phot.magfloatnullableP70flux? Flux at PACS 70 micron bandJyphot.flux.density;em.IR.30-60umdoublenullableP160flux? Flux at PACS 160 micron bandJyphot.flux.density;em.mm.1500-3000GHzdoublenullable