J/ApJ/710/1142ivo://CDS.VizieR/J/ApJ/710/1142doi:10.26093/cds/vizier.17101142CDSBurgasser A.J.Cruz K.L.Cushing M.Gelino C.R.Looper D.L.,Faherty J.K.Kirkpatrick J.D.Reid I.N.2023-01-12T11:28:20Z2012-04-17T13:08:41ZCDS support team

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

cds-question@unistra.frspectroscopic-binary-starsinfrared-photometrystellar-spectral-typeslate-type-starsinfrared-astronomyspectroscopyWe report the identification of 17 candidate brown dwarf binaries whose components straddle the L dwarf/T dwarf transition. These sources were culled from a large near-infrared spectral sample of L and T dwarfs observed with the Infrared Telescope Facility SpeX spectrograph. Candidates were selected on the basis of spectral ratios which segregate known (resolved) L dwarf/T dwarf pairs from presumably single sources. Composite templates, constructed by combining 13581 pairs of absolute flux-calibrated spectra, are shown to provide statistically superior fits to the spectra of our 17 candidates as compared to single templates. Ten of these candidates appear to have secondary components that are significantly brighter than their primaries over the 1.0-1.3um band, indicative of rapid condensate depletion at the L dwarf/T dwarf transition. Our results support prior indications of enhanced multiplicity amongst early-type T dwarfs; 53+/-7% of the T0-T4 dwarfs in our spectral sample are found to be either resolved or unresolved (candidate) pairs, although this is consistent with an intrinsic (volume complete) brown dwarf binary fraction of only 15%. If verified, this sample of spectral binaries more than doubles the number of known L dwarf/T dwarf transition pairs, enabling a broader exploration of this poorly understood phase of brown dwarf atmospheric evolution.2010ApJ...710.1142Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/710/1142CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)J/A+A/497/619 : New ultra-cool dwarfs from SDSS and 2MASS (Zhang+, 2009)J/ApJ/676/1281 : L and T dwarfs in 2MASS/SDSS (Metchev+, 2008)J/AJ/136/1290 : Ultracool dwarfs from the 2MASS (Reid+, 2008)J/ApJ/689/1295 : Lithium test implications for brown dwarfs (Kirkpatrick+,J/AJ/134/1162 : 11 new T dwarfs in 2MASS (Looper+, 2007)J/AJ/133/439 : Luminosity function of M7-L8 ultracool dwarfs (Cruz+, 2007)J/ApJ/637/1067 : Near-IR spectral classification of T dwarfs (Burgasser+, 2006)J/AJ/131/2722 : New L and T dwarfs from the SDSS (Chiu+, 2006)J/PASP/118/659 : RI photometry of 2MASS late M and L dwarfs (Liebert+, 2006)J/AJ/127/3553 : JHK photometry and spectroscopy for L and T dwarfs (Knapp+,J/AJ/127/2856 : Brown dwarfs in the 2MASS Survey (Burgasser+, 2004)J/AJ/126/2487 : T dwarfs in the southern hemisphere (Burgasser+, 2003)J/AJ/126/2421 : 2MASS-Selected sample of ultracool dwarfs (Cruz+, 2003)J/AJ/125/3302 : HST binary very low mass stars and brown dwarfs (Gizis+, 2003)J/ApJ/564/421 : Spectra of T dwarfs. I. (Burgasser+, 2002)J/AJ/123/3409 : SDSS M, L, and T dwarfs (Hawley+, 2002)http://www.vlmbinaries.org/ : Very low-mass binaries archive onlinehttp://pono.ucsd.edu/~adam/browndwarfs/spexprism/ : The SpeX Prism spectralhttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/710/1142https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/710/1142http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/710/1142https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/710/1142https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/710/1142http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/710/1142GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/710/1142/bincand (Summary of binary candidates (tables 6 and 10 of the paper))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/710/1142/bincand?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/710/1142/bincand?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/710/1142/bincand?GETtext/xml+votable180.050000true41.957445-16.5203550.005555555555555556Cone search capability for table J/ApJ/710/1142/table1 (New SpeX spectral observations)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/710/1142/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/710/1142/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/710/1142/table1?GETtext/xml+votable180.050000true4.2480458-40.9483750.005555555555555556Cone search capability for table J/ApJ/710/1142/table2 (Spectral templates)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/710/1142/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/710/1142/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/710/1142/table2?GETtext/xml+votable180.050000true0.056416725.90502780.0055555555555555566/320 439 544 736 763 1765 2083 2291 4316 4453 4689 4709 4719 4783 4790 4825 4875 4948 5065 5077 5200 5211 5317 5413 5666 5919 6163 6261 6597 6613 6625 6783 7033 7204 7220 7291 7364 7369 7592 7786 7821 8223 8348 8371 8402 8478 8625 8715 8746 9009 9063 9072 9136 9173 9318 9564 9597 9642 9715 9784 9914 9959 9986 10628 10654 11164 11257 11292 11450 11453 11587 11834 11940 12369 12430 12466 12541 12579 12592 12744 13341 13425 13544 13678 15144 15651 16778 16850 16873 17166 17530 18032 18156 18266 18281 18300 18595 18683 18719 19090 19121 19138 19144 19647 19747 19813 19857 19895 19912 20273 20415 21157 21296 21880 22521 22681 22810 23274 24573 24631 25015 25100 25314 25443 25853 26020 26196 26210 26248 27201 27395 27414 27493 27514 27653 27698 27730 28277 28316 28344 28346 28471 28530 30061 30919 31011 31062 31268 31319 31411 31419 31714 31992 32337 32426 32457 33767 34196 34291 34780 35495 35518 35538 35572 35902 35906 36072 36602 36640 38363 38472 38683 39482 40397 40882 42739 44118 44286 44807 46334 46384 46607 46846 47357 47640 48409 48593 48759 48907 48957 490771.398457827073138e-19 1.7798557115773645e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/710/1142?format=asciiInfrareddefaultJ/ApJ/710/1142/bincandSummary of binary candidates (tables 6 and 10 of the paper)SpT1pPublished MK spectral typemeta.ref;src.spTypechare_SSpT? SSpT uncertaintystat.errorintnullableJmag2MASS J-band magnitudemagphot.mag;em.IR.Jfloate_JmagJmag uncertaintymagstat.error;phot.magfloatl_J-KsLimit flag on J-Ksmeta.code.error;phot.color;em.IR.JcharJ-Ks2MASS J-Ks color indexmagphot.color;em.IR.J;em.IR.Kfloate_J-Ks? J-Ks uncertaintymagstat.error;phot.color;em.IR.JfloatnullableC[2,6] Number of selection criteria satisfied (2)meta.numberintClass[Pbl/Oth] Pbl: Probable binaries or Oth: Other sourcessrc.classchare_SpT1p? SpT1p uncertaintystat.errorfloatnullableSpT2pSpeX MK spectral type (3)src.spTypechare_SpT2p? SpT2p uncertaintystat.errorintnullableSpT1Primary MK spectral typesrc.spTypechare_SpT1SpT1 uncertaintystat.errorfloatSpT2Secondary MK spectral typesrc.spTypechare_SpT2SpT2 uncertaintystat.errorfloatdJmagJmag difference between primary and secondarymagphot.mag;arith.difffloatSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSet[Sg/Wk] Sg: strong vs Wk: weak candidatesmeta.idcharNameSource name (1)meta.id;meta.maincharOSpTOptical MK spectral typesrc.spTypecharNSpTNear-IR MK spectral typesrc.spTypechare_NSpT? NSpT uncertaintystat.errorfloatnullableSSpTSpeX MK spectral typesrc.spTypechare_dJmagdJmag uncertaintymagstat.error;phot.magfloatl_CLLimit flag on CLmeta.code.errorcharCLConfidence limit (see Sect. 4.2)%stat.fit.param;arith.ratiointObs?[Yes/No ] Near-infrared HST or Keck AO observations?meta.codecharf_Obs?[b] HST observation (4)meta.codecharNoteNotesmeta.notecharAllDisplay all the data for this object within the tablesmeta.ref.urlchar2MDisplay the 2MASS data (Cutri et al. 2003, Cat. II/246)meta.ref.urlchar_RAPositions from Simbad (right ascension part)degpos.eq.ra;meta.main_DEPositions from Simbad (declination part)degpos.eq.dec;meta.mainJ/ApJ/710/1142/table1New SpeX spectral observationsSimbadNameSimbad column added by the CDSmeta.idcharnullableNSpTNear-IR MK spectral typesrc.spTypecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJmag2MASS Johnson J band magnitudemagphot.mag;em.IR.Jfloate_Jmag? Uncertainty in Jmagmagstat.error;phot.magfloatnullableDateUT date of the observationtime.epoch;obsnullableObsObserver initialsobs.observercharExpExposure timestime.duration;obs.exposureintSlitSlit sizearcsecinstr.setupfloatAirAirmassobs.airMassfloatCalCalibration starmeta.idcharNameSource namemeta.id;meta.mainchare_NSpT? NSpT uncertaintystat.errorfloatnullablel_JmagLimit flag on Jmagmeta.code.errorcharAllDisplay all the data for this object within the tablesmeta.ref.urlchar2MDisplay the 2MASS data (Cutri et al. 2003, Cat. II/246)meta.ref.urlchar_RAPositions from Simbad or 2MASS names (right ascension part)degpos.eq.ra;meta.main_DEPositions from Simbad or 2MASS names (declination part)degpos.eq.dec;meta.mainOSpTOptical MK spectral typesrc.spTypecharJ/ApJ/710/1142/table2Spectral templatesSimbadNameSimbad column added by the CDSmeta.idcharnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameSource namemeta.id;meta.maincharf_Name[b-f ] Flag(s) on Name (1)meta.codecharOSpTOptical MK spectral typesrc.spTypecharNSpTNear-IR MK spectral typesrc.spTypechare_NSpT? NSpT uncertaintystat.errorfloatnullableSSpTSpeX MK spectral typesrc.spTypechare_SSpT? SSpT uncertaintystat.errorintnullableJmag2MASS Johnson J band magnitudemagphot.mag;em.IR.Jfloate_JmagUncertainty in Jmagmagstat.error;phot.magfloatf_Jmag[e] Flag on Jmag (1)meta.codecharl_J-KsLimit flag on J-Ksmeta.code.error;phot.color;em.IR.JcharJ-Ks2MASS (J-K_s_) color indexmagphot.color;em.IR.J;em.IR.Kfloate_J-Ks? Uncertainty in J-Ksmagstat.error;phot.color;em.IR.Jfloatnullablef_J-Ks[e] Flag on J-Ks (1)meta.codecharRefReferences (see refs.dat file) (2)meta.refcharAllDisplay all the data for this object within the tablesmeta.ref.urlchar2MDisplay the 2MASS data (Cutri et al. 2003, Cat. II/246)meta.ref.urlchar_RAPositions from Simbad or 2MASS names (right ascension part)degpos.eq.ra;meta.main_DEPositions from Simbad or 2MASS names (declination part)degpos.eq.dec;meta.mainJ/ApJ/710/1142/refsReferencesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRefReference codemeta.noteintBibCodeBibcodemeta.bib.bibcodecharAutFirst author's namemeta.bib.authorcharCommCommentmeta.notechar