J/A+A/632/A46ivo://CDS.VizieR/J/A+A/632/A46doi:10.26093/cds/vizier.36320046CDSVenuti L.Stelzer B.Alcala J.M.Manara C.F.Frasca A.Jayawardhana R.,Antoniucci S.Argiroffi C.Natta A.Nisini B.Randich S.Scholz A.2020-04-07T08:13:24Z2019-11-26T08:24:01ZCDS support team

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

cds-question@unistra.frm-starspre-main-sequence-starsaccretionspectroscopyinfrared-astronomyultraviolet-astronomyMeasurements of the protoplanetary disk frequency in young star clusters of different ages indicate disk lifetimes <10Myr. However, our current knowledge of how mass accretion in young stars evolves over the lifespans of disks is subject to many uncertainties, especially at the lower stellar masses. In this study, we investigate ongoing accretion activity in the TW Hydrae association (TWA), the closest association of pre-main sequence stars with active disks. The age (8-10Myr) and the proximity of the TWA render it an ideal target to probe the final stages of disk accretion down to brown dwarf masses. The study is based on homogeneous spectroscopic data from 300nm to 2500nm, obtained synoptically with X-shooter, which allows simultaneous derivation of individual extinction, stellar parameters, and accretion parameters for each star. The continuum excess emission diagnostics is used to estimate the accretion luminosities and mass accretion rates of our disk-bearing targets, and the shape and intensity of permitted and forbidden emission lines are analyzed to probe the physics of the star-disk interaction environment.2019A&A...632A..46Vhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/632/A46CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/632/A46https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/632/A46http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/632/A46https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/632/A46https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/632/A46http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/632/A46GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/632/A46/list (List of X-shooter spectra for all TWA targets)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/632/A46/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/632/A46/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/632/A46/list?GETtext/xml+votable180.050000true165.46632083-34.704722220.0055555555555555566/24580-24581 24629 24644 24740 24763 38054 38347 38382 43718https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/632/A46?format=asciiUVInfrareddefaultJ/A+A/632/A46/listList of X-shooter spectra for all TWA targetsSimbadNameSimbad column added by the CDSmeta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameObject identifiermeta.id;meta.maincharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainSpTypeSpectral type of the objectsrc.spTypecharObsID of the observing programmeta.idcharspShow the spectrummeta.ref.urlcharUVBName of the UVB spectrum file in subdirectory fitsmeta.id;meta.filecharVISName of the VIS spectrum file in subdirectory fitsmeta.id;meta.filecharNIRName of the NIR spectrum file in subdirectory fitsmeta.id;meta.filechartUVBSingle exposure time for UVB spectrumstime.duration;obs.exposureinttVISSingle exposure time for VIS spectrumstime.duration;obs.exposureinttNIRSingle exposure time for NIR spectrumstime.duration;obs.exposureintsUVBWidth of the slit used for UVB spectrumarcsecinstr.setupfloatsVISWidth of the slit used for VIS spectrumarcsecinstr.setupfloatsNIRWidth of the slit used for NIR spectrumarcsecinstr.setupfloat