J/AJ/158/235ivo://CDS.VizieR/J/AJ/158/235doi:10.26093/cds/vizier.51580235CDSGetman K.V.Feigelson E.D.Kuhn M.A.Broos P.S.Garmire G.P.2020-02-06T12:32:35Z2020-02-06T13:21:00ZCDS support team

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

cds-question@unistra.frh-ii-regionsstar-forming-regionsx-ray-sourcespre-main-sequence-starsinfrared-photometrystellar-agesIRAS 09002-4732 is a poorly studied embedded cluster of stars in the Vela Molecular Ridge at a distance of 1.7 kpc. Deep observations with the Chandra X-ray Observatory, combined with existing optical and infrared surveys, produce a catalog of 441 probable pre-main-sequence members of the region. The stellar spatial distribution has two components: most stars reside in a rich, compact, elliptical cluster, but a minority reside within a molecular filament several parsecs long that straddles the cluster. The filament has active distributed star formation with dozens of unclustered protostars. The cluster pre-main-sequence population is =<0.8 Myr old and deeply embedded; its most massive member is extremely young, producing an ultracompact H II region. The cluster total population deduced from the X-ray luminosity function is surprisingly rich, twice that of the Orion Nebula Cluster. The cluster core is remarkably dense where strong N-body interactions should be occurring; its initial mass function may be deficient in massive stars. We infer that IRAS 09002-4732 is a rare case where a rich cluster is forming today in a molecular filament, consistent with astrophysical models of cluster formation in clouds that involve the hierarchical formation and merging of groups in molecular filaments.2019AJ....158..235Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/158/235CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/chandra : The Chandra Archive Log (CXC, 1999-2014)II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)IX/57 : The Chandra Source Catalog (CSC), Release 2.0 (Evans+, 2019)J/A+A/434/987 : Near-IR sources around IRAS 09002-4732 (Apai+, 2005)J/ApJS/209/31 : The MYStIX IR-Excess Source catalog (MIRES) (Povich+, 2013)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/158/235https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/158/235http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/158/235https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/158/235https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/158/235http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/158/235GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/158/235/table2 (Candidate X-ray sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/158/235/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/158/235/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/158/235/table2?GETtext/xml+votable180.050000true135.20547111-47.783938060.005555555555555556Cone search capability for table J/AJ/158/235/table4 (MIRES sources from Povich et al. (2013, J/ApJS/209/31) undetected in X-rays)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/158/235/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/158/235/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/158/235/table4?GETtext/xml+votable180.050000true135.2637-47.69150.0055555555555555566/37850 378722.0616683193919197e-20 1.7003137259100215e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/158/235?format=asciiX-rayInfrareddefaultJ/AJ/158/235/table2Candidate X-ray sourcesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCXOUChandra X-ray Observatory Unidentified source (HHMMSS.ss+DDMMSS.s)meta.id;meta.maincharRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainePos[0.03/2.33] Position error (63%)arcsecstat.error;posfloatOffAxis[0.4/11.6] Off-axis angle on detectorarcmininstr.offset;instr.detfloatNetCt[1.1/287.8] Net countsctphot.count;em.X-rayfloate_NetCt[1.5/17.1] Error on NetCtctstat.errorfloatBkCt[0.1/20.6] Background countsctinstr.backgroundfloatfPSF[0.39/0.91] Point Spread Function fractioninstr.det.psf;arith.ratiofloatProbB[-5/-0.7] Log probability of source existence (1)stat.fit.goodnessfloatAnomAnomaly flag (2)meta.codecharVarVariability flag (3)meta.code;src.varcharMedE[0.5/7.6] Median photon energy of net countskeVem.energyfloatJ/AJ/158/235/table3X-ray PMS members of IRAS 09002-4732recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/386] IRAS 09002-4732 probable member sequence numbermeta.idintCXOUChandra X-ray Observatory Unidentified source (HHMMSS.ss+DDMMSS.s)meta.id;meta.maincharlogLX[29.75/32.13]? Log X-ray luminosity, absorption-corrected, 0.5-8 keV (in erg/s)log(1e-07W)phys.luminosity;em.X-rayfloatnullablee_logLX[0.08/0.7]? Error of logLX (in erg/s)log(1e-07W)stat.errorfloatnullablelogNH[20.95/24]? Log hydrogen column density inferred from X-ray median energylog(cm**-2)phys.columnDensityfloatnullablee_logNH[0.08/0.96]? Error of logNHlog(cm**-2)stat.errorfloatnullable2MASS2MASS catalog identifier (HHMMSSss+DDMMSSs)meta.idcharJmag[10.54/18.44]? 2MASS J band magnitudemagphot.mag;em.IR.Jfloatnullablee_Jmag[0.02/0.25]? Error of Jmagmagstat.error;phot.mag;em.IR.JfloatnullableHmag[9.71/16.95]? 2MASS H band magnitudemagphot.mag;em.IR.Hfloatnullablee_Hmag[0.02/0.35]? Error of Hmagmagstat.error;phot.mag;em.IR.HfloatnullableKsmag[9.14/16.25]? 2MASS K_s_ band magnitudemagphot.mag;em.IR.Kfloatnullablee_Ksmag[0.02/0.25]? Error of Ksmagmagstat.error;phot.mag;em.IR.KfloatnullableQflgQuality flag of 2MASS photometry (1)meta.code.qual;photcharIRX[-2.59/1.96]? Infrared excess from 2MASS photometrymagphot.color.excessfloatnullableAgeJX[0.1/2.6]? Stellar age from 2MASS and Chandra photometryMyrtime.agefloatnullable3.6mag[7.85/14.98]? Spitzer/IRAC 3.6{mu}m (Channel 1) magnitudemagphot.mag;em.IR.3-4umfloatnullablee_3.6mag[0.03/0.21]? Error of 3.6magmagstat.errorfloatnullable4.5mag[7.34/14.29]? Spitzer/IRAC 4.5{mu}m (Channel 2) magnitudemagphot.mag;em.IR.4-8umfloatnullablee_4.5mag[0.03/0.31]? Error of 4.5magmagstat.errorfloatnullable5.6mag[6.69/13.16]? Spitzer/IRAC 5.6{mu}m (Channel 3) magnitudemagphot.flux.density;em.IR.4-8umfloatnullablee_5.6mag[0.02/0.35]? Error of 5.6magmagstat.errorfloatnullable8.0mag[5.66/12.94]? Spitzer/IRAC 8.0{mu}m (Channel 4) magnitudemagphot.flux.density;em.IR.8-15umfloatnullablee_8.0mag[0.03/0.34]? Error of 8.0magmagstat.errorfloatnullableSpIndex[-3.54/5.48]? Spectral index from 2MASS and Spitzer photometryspect.indexfloatnullablermag[12.31/22.68]? VPHAS r band magnitudemagphot.mag;em.opt.Rfloatnullablee_rmag[0/0.28]? Error of rmagmagstat.error;phot.mag;em.opt.Rfloatnullableimag[12.35/22.01]? VPHAS i band magnitudemagphot.mag;em.opt.Ifloatnullablee_imag[0/0.24]? Error of imagmagstat.error;phot.mag;em.opt.IfloatnullableAV(JHK)[0/8.1]? Visual band absorption from 2MASS photometrymagphys.absorptionfloatnullableAge(ri)[0.1/7]? Stellar age from VPHAS photometryMyrtime.agefloatnullablePlx[-1.943/5.99]? Gaia parallaxmaspos.parallaxfloatnullablee_Plx[0.019/1.846]? Error of Plxmasstat.error;pos.parallaxfloatnullableJ/AJ/158/235/table4MIRES sources from Povich et al. (2013, J/ApJS/209/31) undetected in X-rayse_alpha[0.12/0.47] Error of SED slopestat.error;pos.eq.rafloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[387/441] IRAS 09002-4732 probable member sequence numbermeta.idintIRACSpitzer/IRAC designation (Galactic coordinates; GLLL.llll+BB.bbbb)meta.id;meta.maincharRAJ2000Approximate Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Approximate Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainJmag[14.13/17.03]? UKIDSS J band magnitudemagphot.mag;em.IR.Jfloatnullablee_Jmag[0.05/0.21]? Error of J band magnitudemagstat.error;phot.mag;em.IR.JfloatnullableHmag[12.73/16.34]? UKIDSS H band magnitudemagphot.mag;em.IR.Hfloatnullablee_Hmag[0.05/0.22]? Error of H band magnitudemagstat.error;phot.mag;em.IR.HfloatnullableKmag[11.61/15.3]? UKIDSS K band magnitudemagphot.mag;em.IR.Kfloatnullablee_Kmag[0.05/0.18]? Error of K band magnitudemagstat.error;phot.mag;em.IR.Kfloatnullable3.6mag[8.23/14.64] Spitzer/IRAC Channel 1 magnitudemagphot.mag;em.IR.3-4umfloate_3.6mag[0.05/0.17] Error or 3.6magmagstat.errorfloat4.5mag[6.92/13.98] Spitzer/IRAC Channel 2 magnitudemagphot.mag;em.IR.4-8umfloate_4.5mag[0.05/0.16] Error of 4.5magmagstat.errorfloat5.6mag[5.93/13.16]? Spitzer/IRAC Channel 3 magnitudemagphot.flux.density;em.IR.4-8umfloatnullablee_5.6mag[0.1/0.32]? Error of 5.6magmagstat.errorfloatnullable8.0mag[5.1/12.32]? Spitzer/IRAC Channel 4 magnitudemagphot.flux.density;em.IR.8-15umfloatnullablee_8.0mag[0.1/0.3]? Error of 8.0magmagstat.errorfloatnullablealpha[-1.8/2.02] Infrared Spectral Energy Distribution slopearith.grad;instr.bandwidthfloatNalpha[2/4] Number of photometric points in SED slopemeta.numberintStage[-1/2] Estimated evolutionary stage (1)meta.codeint