J/A+A/605/A85ivo://CDS.VizieR/J/A+A/605/A85doi:10.26093/cds/vizier.36050085CDSPreibisch T.Flaischlen S.Gaczkowski B.Townsley L.Broos P.2019-09-04T12:09:44Z2017-09-14T09:12:11ZCDS support team

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

cds-question@unistra.fropen-star-clustersx-ray-sourcesinfrared-sourcesNGC 3293 is a young stellar cluster at the northwestern periphery of the Carina Nebula Complex that remained poorly explored until now. We want to characterize the stellar population of NGC 3293 in order to evaluate key parameters of the cluster population like the age and the mass function, and to test claims of an abnormal IMF and a deficit of M<=2.5M_{sun}_ stars. WWe performed a deep (70 ksec) X-ray observation of NGC 3293 with Chandra and detected 1026 individual X-ray point sources. These X-ray data directly probe the low-mass (M<=2M_{sun}_) stellar population by means of the strong X-ray emission of young low-mass stars. We identify counterparts for 74% of the X-ray sources in our deep near-infrared images. Our data clearly show that NGC 3293 hosts a large population of ~solar-mass stars, refuting claims of a lack of M<=2.5M_{sun}_ stars. The analysis of the color-magnitude diagram suggests an age of ~8-10Myr for the low-mass population of the cluster. There are at least 511 X-ray detected stars with color-magnitude positions that are consistent with young stellar members within 7 arcmin from the cluster center. The number ratio of X-ray detected stars in the [1-2]M_{sun}_ range versus the M<=5M_{sun}_ stars (known from optical spectroscopy) is well consistent with the expectation from a normal field initial mass function. Most of the early B-type stars and ~20% of the later B-type stars are detected as X-ray sources. Our data shows that NGC 3293 is one of the most populous stellar clusters in the entire Carina Nebula Complex (only excelled by Tr 14, and very similar to Tr 16 and Tr 15). The cluster has probably harbored several O-type stars, the supernova explosions of which may have had an important impact on the early evolution of the Carina Nebula Complex.2017A&A...605A..85Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/605/A85CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/341 : VPHAS+ DR2 survey (Drew+, 2016)J/A+A/437/467 : VLT-FLAMES survey of massive stars (Evans+, 2005)J/A+A/572/A116 : The VISTA Carina Nebula Survey (Preibisch+, 2014)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/605/A85https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/605/A85http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/605/A85https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/605/A85https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/605/A85http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/605/A85GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/605/A85/table1 (Primary Chandra Catalog: Basic Source Properties)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/605/A85/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/605/A85/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/605/A85/table1?GETtext/xml+votable180.050000true158.55351306-58.4594450.005555555555555556Cone search capability for table J/A+A/605/A85/table2 (VISTA and VST source identification for the X-ray sources in NGC 3293)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/605/A85/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/605/A85/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/605/A85/table2?GETtext/xml+votable180.050000true158.6224167-58.21466670.0055555555555555566/38018-38019 38024-38025https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/605/A85?format=asciiX-rayInfrareddefaultJ/A+A/605/A85/table1Primary Chandra Catalog: Basic Source PropertiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintmoreindicates VISTA and VST identification (table 2) and X-ray luminosities for B-type stars (table 3)meta.ref.urlcharSeqX-ray catalog sequence number, sorted by RAmeta.idintprimaryCXNameIAU designation of the X-ray source (HHMMSS.ss+DDMMSS.s, CXONGC3293 JHHMMSS.ss+DDMMSS.s)meta.id;meta.maincharRAJ2000Right ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.maine_PosPosition errorarcsecstat.errorfloatThetaOff-axis anglearcmininstr.offsetfloatCtTnetNet counts in the total energy band (0.5-8keV)ctphot.count;em.X-rayfloate_CtTnet1-sigma errors on net countsctstat.errorfloatBctBackground counts expected in the source extraction regionctinstr.background;obs.fieldfloatCtHnetNet counts in the hard energy band (2-8keV)ctphot.count;em.X-rayfloatPSFfracFraction of the PSF (at 1.497keV) enclosed within the extraction regioninstr.det.psffloatSigniPhotometric significancestat.fit.goodness;photfloatl_logPBLimit flag on logPBmeta.code.errorcharlogPBLogarithmic probability that extracted counts are solely from backgroundstat.fit.goodnessfloatAnom[ag] Source anomalies (1)meta.codecharVar[abc] Variability characterization based on K-S statistic (2)meta.codecharEmedBackground-corrected median photon energykeVem.energyfloatSimbadSimbad column added by the CDSmeta.ref.urlcharJ/A+A/605/A85/table2VISTA and VST source identification for the X-ray sources in NGC 3293recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqChandra X-ray catalog sequence number (1)meta.idintCXNameChandra X-ray catalog source name (1)meta.id;meta.maincharVCNSIdentifier in the VISTA VCNS source catalog or 2MASS name (2)meta.idcharVPHASIdentifier in the VST VPHAS-DR2 source catalog (3)meta.idcharsourceIDSourceID in the VST VPHAS-DR2 source catalog (3)meta.idchar_RAPosition from CXName (right ascension part)degpos.eq.ra;meta.main_DEPosition from CXName (declination part)degpos.eq.dec;meta.mainJ/A+A/605/A85/table3X-ray luminosities of B-type stars in NGC 3293recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintESLNGC 3293 ESL Number (based on Evans et al. 2005, Cat. J/A+A/437/467, Cl* NGC 3293 ESL NNN in Simbad)meta.idcharNameName of the star (as listed in SIMBAD, if available)meta.id;meta.maincharSeq? X-ray catalog sequence numbermeta.idintnullableSpTypeSpectral typesrc.spTypecharLX? X-ray luminosity for stars with X-ray detection (1)1e-07Wphys.luminosity;em.X-raydoublenullableulLX? Upper limit to the X-ray luminosity for stars without X-ray detection1e-07Wphys.luminosity;em.X-raydoublenullablelogLX/Lb? Logarithm of the X-ray to bolometric luminosity ratio (1)phys.luminosity;arith.ratiofloatnullableullogLX/Lb? Logarithm of the upper limit to the X-ray to bolometric luminosity ratiophys.luminosity;arith.ratiofloatnullableSimbadSimbad column added by the CDSmeta.ref.urlchar