J/A+A/564/A55ivo://CDS.VizieR/J/A+A/564/A55doi:10.26093/cds/vizier.35640055CDSManjavacas E.Bonnefoy M.Schlieder J.E.Allard F.Rojo P.Goldman B.,Chauvin G.Homeier D.Lodieu N.Henning T.2014-04-18T18:48:55Z2014-04-04T08:33:29ZCDS support team

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

cds-question@unistra.frdwarf-starslate-type-starsspectroscopyGravity modifies the spectral features of young brown dwarfs (BDs). A proper characterization of these objects is crucial for the identification of the least massive and latest-type objects in star-forming regions, and to explain the origin(s) of the peculiar spectrophotometric properties of young directly imaged extrasolar planets and BD companions. We obtained medium-resolution (R~1500-1700) near-infrared (1.1-2.5um) spectra of seven young M9.5-L3 dwarfs classified at optical wavelengths. We aim to empirically confirm the low surface gravity of the objects in the near-infrared. We also test whether self-consistent atmospheric models correctly represent the formation and the settling of dust clouds in the atmosphere of young late-M and L dwarfs. We used the Infrared Spectrometer And Array Camera (ISAAC) at the Very Large Telescope (VLT) to obtain the spectra of the targets. We compared the spectra to those of mature and young BDs, and to young late-type companions to nearby stars with known ages, to identify and study gravity-sensitive features. We computed spectral indices weakly sensitive to the surface gravity to derive near-infrared spectral types. Finally, we found the best fit between each spectrum and synthetic spectra from the BT-Settl 2010 and 2013 atmospheric models. Using the best fit, we derived the atmospheric parameters of the objects and identified which spectral characteristics the models do not reproduce.2014A&A...564A..55Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/564/A55CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/564/A55https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/564/A55http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/564/A55https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/564/A55https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/564/A55http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/564/A55GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/564/A55/table1 (List of studied objects)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/564/A55/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/564/A55/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/564/A55/table1?GETtext/xml+votable180.050000true191.30875-44.4852780.0055555555555555566/13455 35387 41127 43575 45108 46094 48455https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/564/A55?format=asciiOpticaldefaultJ/A+A/564/A55/table1List of studied objectsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameObject namemeta.id;meta.maincharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainspplot of spectrummeta.ref.urlcharfitsDownload the FITS spectrummeta.ref.urlcharFileNameName of the FITS file in subdirectory spmeta.id;meta.fitschar