J/AJ/160/35ivo://CDS.VizieR/J/AJ/160/35doi:10.26093/cds/vizier.51600035CDSSchaefer G.H.Beck T.L.Prato L.Simon &.M.2021-02-19T07:32:21Z2020-11-02T09:15:28ZCDS support team

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

cds-question@unistra.frmultiple-starsinfrared-photometryWe present results from adaptive optics imaging of the T Tauri triple system obtained at the Keck and Gemini Observatories in 2015-2019. We fit the orbital motion of T Tau Sb relative to Sa and model the astrometric motion of their center of mass relative to T Tau N. Using the distance measured by Gaia, we derived dynamical masses of M_Sa_=2.05{+/-}0.14M_{sun}_ and M_Sb_=0.43{+/-}0.06M_{sun}_. The precision in the masses is expected to improve with continued observations that map the motion through a complete orbital period; this is particularly important as the system approaches periastron passage in 2023. Based on published properties and recent evolutionary tracks, we estimate a mass of ~2M_{sun}_ for T Tau N, suggesting that T Tau N is similar in mass to T Tau Sa. Narrowband infrared photometry shows that T Tau N remained relatively constant between late 2017 and early 2019 with an average value of K=5.54{+/-}0.07mag. Using T Tau N to calibrate relative flux measurements since 2015, we found that T Tau Sa varied dramatically between 7.0 and 8.8mag in the K band over timescales of a few months, while T Tau Sb faded steadily from 8.5 to 11.1mag in the K band. Over the 27yr orbital period of the T Tau S binary, both components have shown 3-4mag of variability in the K band, relative to T Tau N.2020AJ....160...35Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/160/35CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/ApJS/165/256 : Fluorescent H_2_ emission from T Tauri stars (Herczeg+, 2006)J/A+A/479/827 : UBVR light curves of weak-line T Tauri stars (Grankin+, 2008)J/ApJ/718/1353 : Light curve of the triple system NLTT 41135 (Irwin+, 2010)J/ApJ/744/121 : Far-UV spectroscopy of T Tau stars (Yang+, 2012)J/MNRAS/434/966 : Measurements of Li in T-Tauri stars (Sergison+, 2013)J/A+A/590/A78 : NGC2264 weak-line T Tauri lithium abundances (Bouvier+, 2016)J/AJ/152/11 : Orbits of four triple stars (Tokovinin, 2016)J/AJ/152/198 : Periods of 4-10Myr old T Tauri mem. of Orion OB1 (Karim+,2016)J/A+A/611/A69 : B,V and R band polarimetry of lambda Tau (Berdyugin+, 2018)J/A+A/622/A72 : Intermediate-mass T Tau stars spectra (Villebrun+, 2019)J/AJ/159/135 : LCs of the binary T Tauri star V582 Mon (Garcia Soto+, 2020)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/160/35https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/160/35http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/160/35https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/160/35https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/160/35http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/160/35GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapInfrareddefaultJ/AJ/160/35/table1NIR AO measurements of T Tau triple systemrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObs[2015/2019] UT Year of observationtime.epoch;obsJY[2015/2020] Julian Yearyrtime.epochdoubleCompComponent identification (1)meta.idcharSep[65.2/692]? Separationmaspos.angDistancefloatnullablee_Sep[0.4/23.7]? Error in Sepmasstat.errorfloatnullablePA[6.25/358]? Position angledegpos.posAngfloatnullablee_PA[0.03/12]? Error in PAdegstat.errorfloatnullableFiltFilter (2)meta.id;instr.filtercharFratio[0.0004/2.94] Flux ratio; f2/f1phot.flux;arith.ratiofloate_Fratio[0.0003/0.57] Error in Fratiostat.errorfloatTelCode for telescope; G=Gemini North (129 occurrences), K=Keck II (24 occurrences)meta.id;instr.telcharJ/AJ/160/35/table2Absolute photometry, Gemini observationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJY[2017/2020] Julian Yearyrtime.epochdoubleFiltFilter (5 H-, 16 K- or 14 L-band filter)meta.id;instr.filtercharMAGN[5.02/6.44] Absolute magnitude of T Tau Nmagphys.magAbsfloate_MAGN[0.03/1.9] Error in MagNmagstat.errorfloatMAGSa[5/13] Absolute magnitude of T Tau Samagphys.magAbsfloate_MAGSa[0.08/1.9] Error in MagSamagstat.errorfloatMAGSb[8.36/13.3] Absolute magnitude of T Tau Sbmagphys.magAbsfloate_MAGSb[0.2/3.5] Error in MagSbmagstat.errorfloat