J/A+A/319/184ivo://CDS.VizieR/J/A+A/319/184doi:10.26093/cds/vizier.33190184CDSAlcala J.M.Krautter J.Covino E.Neuhaeuser R.Schmitt J.H.M.M.,Wichmann R.1999-02-26T14:10:34Z1999-02-26T15:10:28ZCDS support team

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

cds-question@unistra.frpre-main-sequence-starsWe analyse the nature of the optical counterparts of the ROSAT all-sky survey (RASS) X-ray sources identified with new weak-line T Tauri (WTTS) stars in the Chamaeleon star forming region (SFR). The new WTTS are distributed throughout the whole SFR, while the classical T Tauri stars (CTTS) are found only in the cloud cores. Adopting a distance of 150pc we derive the stellar parameters and place the new WTTS in the HR diagram. By comparison with theoretical pre-main sequence (PMS) evolutionary tracks, we find masses in the range of 0.2-2.5M_{sun}_ and ages from a few 10^5^yr to 5x10^7^yr. Many of the youngest WTTS are located far away from the main Chamaeleon dark clouds.1997A&A...319..184Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/319/184CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/319/184https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/319/184http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/319/184https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/319/184https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/319/184http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/319/184GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapROSATOpticaldefaultJ/A+A/319/184/table1Stellar parameters of the new weak-line T Tauri stars (WTTS) in the Chamaeleon complex.recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRXJROSAT all-sky survey source designation Alcala' et al. (1995A&AS..114..109A)meta.id;meta.maincharSpTSpectral typesrc.spTypecharlogTeffLogarithm of effective temperaturelog(K)phys.temperature.effectivefloatAv? Visual stellar extinctionmagphys.absorptionfloatnullableLbol? Bolometric luminositysolLumphys.luminosityfloatnullableRad? Stellar radiussolRadphys.size.radiusfloatnullableRadBE? Stellar radius derived from the Barnes-Evans relation Barnes & Evans (1976MNRAS.174..489B)solRadphys.size.radiusfloatnullableMass? Stellar mass (1)solMassphys.massfloatnullablee_Mass? Error on the stellar mass.solMassstat.errorfloatnullablet? Stellar age (1)Myrtime.agefloatnullablee_t? Error on the stellar age.Myrstat.errorfloatnullableFHa? H-alpha surface fluxmW.m**-2phot.fluxfloatnullablenotesNotes to table (2)meta.notecharJ/A+A/319/184/table2X-ray data of the new WTTS in the Chamaeleon complex.recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRXJROSAT all-sky survey source designation Alcala' et al. (1995A&AS..114..109A) (1)meta.id;meta.maincharHR1Hardness ratio 1phot.flux;arith.ratiofloate_HR1Error on hardness ratio 1stat.errorfloatHR2Hardness ratio 2phot.flux;arith.ratiofloate_HR2Error on hardness ratio 2stat.errorfloatlogNHLogarithm of Hydrogen column densitylog(cm**-2)phys.columnDensityfloatkTxX-ray emission energykeVem.energyfloate_kTxError on X-ray emission energykeVstat.errorfloatECFEnergy conversion factor1e-18J.count**-1arith.factorfloate_ECFError on the energy conversion factor1e-18J.count**-1stat.errorfloatl_ECFLimit flag on ECFmeta.code.errorcharlogLxLogarithm of the X-ray luminositylog(1e-07J)phys.luminosity;em.X-rayfloate_logLxError on logarithm of the X-ray luminositylog(1e-07J)stat.errorfloatl_logFxLimit flag on logFxmeta.code.errorcharlogFx? Logarithm of the X-ray surface fluxlog(mW.m**-2)phot.flux;em.X-rayfloatnullablee_logFx? Error on log. of the X-ray surface fluxlog(mW.m**-2)stat.errorfloatnullable