J/ApJ/833/96ivo://CDS.VizieR/J/ApJ/833/96doi:10.26093/cds/vizier.18330096CDSLiu M.C.Dupuy T.J.Allers K.N.2018-08-24T07:58:09Z2018-07-25T07:23:24ZCDS support team

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

cds-question@unistra.frstellar-spectral-typesvisible-astronomytrigonometric-parallaxproper-motionsinfrared-photometryabsolute-magnitudebrown-dwarfsWe present a large, uniform analysis of young (~10-150Myr) ultracool dwarfs, based on new high-precision infrared (IR) parallaxes for 68 objects. We find that low-gravity (VL-G) late-M and L dwarfs form a continuous sequence in IR color-magnitude diagrams, separate from the field population and from current theoretical models. These VL-G objects also appear distinct from young substellar (brown dwarf and exoplanet) companions, suggesting that the two populations may have a different range of physical properties. In contrast, at the L/T transition, young, old, and spectrally peculiar objects all span a relatively narrow range in near-IR absolute magnitudes. At a given spectral type, the IR absolute magnitudes of young objects can be offset from ordinary field dwarfs, with the largest offsets occurring in the Y and J bands for late-M dwarfs (brighter than the field) and mid-/late-L dwarfs (fainter than the field). Overall, low-gravity (VL-G) objects have the most uniform photometric behavior, while intermediate gravity (INT-G) objects are more diverse, suggesting a third governing parameter beyond spectral type and gravity class. We examine the moving group membership for all young ultracool dwarfs with parallaxes, changing the status of 23 objects (including 8 previously identified planetary-mass candidates) and fortifying the status of another 28 objects. We use our resulting age-calibrated sample to establish empirical young isochrones and show a declining frequency of VL-G objects relative to INT-G objects with increasing age. Notable individual objects in our sample include high-velocity (>~100km/s) INT-G objects, very red late-L dwarfs with high surface gravities, candidate disk-bearing members of the MBM20 cloud and {beta} Pic moving group, and very young distant interlopers. Finally, we provide a comprehensive summary of the absolute magnitudes and spectral classifications of young ultracool dwarfs, using a combined sample of 102 objects found in the field and as substellar companions to young stars.2016ApJ...833...96Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/833/96CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toV/144 : NIR spectroscopy of low-mass binaries and brown dwarfs (Mace, 2014)II/328 : AllWISE Data Release (Cutri+ 2013)I/322 : UCAC4 Catalogue (Zacharias+, 2012)II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)J/ApJ/814/118 : L/T transition dwarfs search with PS1+WISE. II. (Best+, 2015)J/MNRAS/454/593 : Young moving groups in solar neighbourhood (Bell+, 2015)J/ApJ/810/158 : M,L,T dwarfs parameters and SEDs (Filippazzo+, 2015)J/ApJS/219/33 : BANYAN. VII. Candidate YMG members from BASS (Gagne+, 2015)J/AJ/149/158 : The BUD sample. I. L dwarf activity sample (Schmidt+, 2015)J/ApJ/798/73 : BANYAN All-Sky Survey (BASS) catalog. V. YMGs (Gagne+, 2015)J/A+A/567/A52 : Membership in stellar kinematic groups (Klutsch+, 2014)J/AJ/147/146 : Spectroscopy of Tuc-Hor candidate members (Kraus+, 2014)J/ApJ/786/29 : Catalog of distances to molecular clouds (Schlafly+, 2014)J/AJ/147/94 : Solar neighborhood. XXXII. L and M dwarfs (Dieterich+, 2014)J/ApJ/784/156 : Plx for 1507 nearby mid-to-late M dwarfs (Dittmann+, 2014)J/A+A/563/A125 : L1642 Herschel maps (Malinen+, 2014)J/AJ/147/34 : SpeX library of L-type dwarfs (Schneider+, 2014)J/AJ/146/156 : APOGEE M-dwarf survey. I. 1st yr veloc. (Deshpande+, 2013)J/ApJ/777/160 : NIR imaging for planets around MG stars (Biller+, 2013)J/PASP/125/809 : New nearby M, L, and T dwarfs (Thompson+, 2013)J/ApJS/205/6 : T dwarf population revealed by WISE (Mace+, 2013)J/ApJ/762/88 : Young stellar kinematic group candidate members (Malo+, 2013)J/A+A/547/A13 : Homogeneous sample of F6-K4 Hyades stars (Tabernero+, 2012)J/ApJ/758/56 : Young M dwarfs within 25pc. II. Kinematics (Shkolnik+, 2012)J/AJ/144/99 : Near-IR spectroscopy of 36 late M dwarfs (Deshpande+, 2012)J/ApJS/201/19 : Hawaii Infrared Parallax Program. I. (Dupuy+, 2012)J/ApJ/752/56 : BDKP. III. Plx for 70 ultracool dwarfs (Faherty+, 2012)J/AJ/143/80 : R Low-mass stars of beta Pic & AB Dor (Schlieder+, 2012)J/A+A/539/A143 : Nearby B-stars parameters and abundances (Nieva+, 2012)J/ApJS/197/19 : First brown dwarfs discovered by WISE (Kirkpatrick+, 2011)J/ApJ/723/684 : NIRSPEC ultracool dwarf radial velocity survey (Blake+, 2010)J/A+A/522/A112 : i'z' photom. of L5 and later dwarf candidates (Reyle+, 2010)J/ApJS/190/100 : NIR proper motion survey using 2MASS (Kirkpatrick+, 2010)J/AJ/139/1808 : Colors and kinematics of SDSS L dwarfs (Schmidt+, 2010)J/A+A/512/A37 : Velocities of 43 nearby L dwarfs (Seifahrt+, 2010)J/ApJ/710/1142 : SpeX spectroscopy of low mass binaries. I. (Burgasser+, 2010)J/ApJ/705/1416 : Sample of M7-M9.5 dwarfs <20pc (Reiners+, 2009)J/ApJ/699/649 : Young M dwarfs within 25pc. I. (Shkolnik+, 2009)J/AJ/137/1 : PMs and astrometry of late-type dwarfs (Faherty+, 2009)J/A+A/493/L27 : Parallaxes of 10 ultracool subdwarfs (Schilbach+, 2009)J/ApJ/689/1295 : Lithium test implications for BDs (Kirkpatrick+, 2008)J/AJ/136/1290 : Ultracool dwarfs from the 2MASS (Reid+, 2008)J/ApJ/676/1281 : L and T dwarfs in 2MASS/SDSS (Metchev+, 2008)J/A+A/481/661 : Hyades brown dwarfs and very low mass stars (Bouvier+, 2008)J/MNRAS/384/1399 : Proper motions of field L and T dwarfs (Jameson+, 2008)J/AJ/135/785 : SDSS-DR5 low-mass star spectroscopic sample (West+, 2008)J/AJ/134/2340 : Membership of Praesepe & Coma Berenices (Kraus+, 2007)J/AJ/133/2258 : Activity and kinematics of ultracool dwarfs (Schmidt+, 2007)J/AJ/133/439 : Luminosity function of M7-L8 ultracool dwarfs (Cruz+, 2007)J/AJ/132/891 : Binaries among nearby L dwarfs (Reid+, 2006)J/AJ/131/2722 : New L and T dwarfs from the SDSS (Chiu+, 2006)J/ApJ/637/1067 : NIR spectral classification of T dwarfs (Burgasser+, 2006)J/other/ARA+A/43.195 : L and T dwarf stars (Kirkpatrick, 2005)J/other/ARA+A/42.685 : Young stars near the Sun (Zuckerman+, 2004)J/AJ/127/3553 : JHK photometry & spectroscopy for L & T dwarfs (Knapp+, 2004)J/AJ/127/2856 : Brown dwarfs in the 2MASS Survey (Burgasser+, 2004)J/AJ/126/3007 : Spectroscopy of faint red NLTT dwarfs (Reid+, 2003)J/AJ/126/2421 : 2MASS-Selected sample of ultracool dwarfs (Cruz+, 2003)J/AJ/126/1526 : IR photometry of ultracool dwarfs (Bouy+, 2003)J/MNRAS/342/1241 : Low-mass stars in M45 and M44 (Pinfield+, 2003)J/AJ/125/3302 : HST binary very low mass stars & brown dwarfs (Gizis+, 2003)J/AJ/123/3409 : SDSS M, L, and T dwarfs (Hawley+, 2002)J/MNRAS/328/45 : Late-type stars members of young groups (Montes+, 2001)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/833/96https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/833/96http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/833/96https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/833/96https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/833/96http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/833/96GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/833/96/sample (CFHT/WIRCam data for the observed (tables 1 and 2))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/833/96/sample?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/833/96/sample?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/833/96/sample?GETtext/xml+votable180.050000true4.860271646.23537050.005555555555555556Cone search capability for table J/ApJ/833/96/phot (Photometry and absolute magnitudes for our and other potentially young objects (tables 6 and 7))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/833/96/phot?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/833/96/phot?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/833/96/phot?GETtext/xml+votable180.050000true11.339230816.57909420.0055555555555555566/221 250 322 483 762 968 2784 3764 4739 5320 5659 5854 6382 7440 8091 9385 9628 10114 10445 12592 13122 13455 13688 13765 13874 13885 16546 16867 16873 17274 17594 17729 18155 18405 18594 18683 18866 19476 19763 20125 20141 20374 20505 20591 20594 20996 21093 21296 22555 22773 22937 22950 23471 23501 23533 24566 24580 24716 24763 25266 26521 26555 26594 27019 27074 27402 31011 31657 31871 32284 32462 33351 34054 34535 34920 35630 38359 38382 39044 41361 43475 43575 43957 44314 44603 44954 47012 47205 47287 47979 48349 48455 48643 491398.650015785639275e-20 2.0429600390310455e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/833/96?format=asciiOpticalInfrareddefaultJ/ApJ/833/96/refsReferencesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRefReference codemeta.noteintBibCodeBibcode of the referencemeta.bib.bibcodecharAuthAuthor's name(s)meta.bib.authorcharCommCommentmeta.notecharJ/ApJ/833/96/sampleCFHT/WIRCam data for the observed (tables 1 and 2)SimbadNameSimbad column added by the CDSmeta.idcharf_NameFlag on Name (1)meta.codecharNameTarget namemeta.id;meta.maincharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintn_Name[ac-e] Note on Name (2)meta.notecharSpTOptical spectral type (3)src.spTypecharf_SpT[D] Flag on SpT (4)meta.codecharSpTirNIR spectral type (3)src.spTypecharf_SpTir[Db] Flag on SpTir (4)meta.codecharFiltFilter ("J" or "K_H2")meta.id;instr.filtercharFWHM[0.5/0.9] Median full width at half maximum measured for the science target over all epochsarcsecspect.line.width;stat.medianfloate_FWHM[0.04/0.3] rms of the FWHMarcsecstat.error;phys.angSizefloatDelAMx[0.01/0.2] Maximum difference in airmass over all epochs ({Delta}AM_max_)obs.param;arith.difffloatNfr[39/308] Total number of frames obtainedmeta.numberintNep[6/15] Number of distinct observing epochs (i.e. nights)meta.numberintDelt[1.2/6.2] Time baseline {Delta}tyrtime.intervalfloatNref[20/1192] Number of reference stars (S/N>10) usedmeta.numberintNcal[14/248] Subset of reference stars used in the absolute astrometric calibration (5)meta.numberintdpi[0.2/1.6] offset from relative to absolute parallax ({pi}_abs_-{pi}_rel_) (6)maspos.parallax;arith.difffloate_dpi[0.02/0.2] dpi uncertaintymasstat.errorfloatRefReference(s) (see refs.dat file)meta.ref;pos.framecharRAJ2000Right ascension in decimal degrees (Eq=J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (Eq=J2000)degpos.eq.dec;meta.mainEpochThe first epoch of our observations; Modified Julian Datedtime.epoch;obsdoublePlx[0.002/0.2] Relative parallaxarcsecpos.parallaxfloate_Plx[0.0008/0.004] Plx uncertaintyarcsecstat.error;pos.parallaxfloatpmRA[-0.8/0.8] Relative proper motion along RA ({mu}_{alpha},rel_cos{delta})arcsec/yrpos.pm;pos.eq.rafloate_pmRA[0.0004/0.003] pmRA uncertaintyarcsec/yrstat.error;pos.pm;pos.eq.rafloatpmDE[-0.8/0.5] Relative proper motion along DEarcsec/yrpos.pm;pos.eq.decfloate_pmDE[0.0004/0.006] pmDE uncertaintyarcsec/yrstat.error;pos.pm;pos.eq.decfloatPlxA[0.003/0.2] Absolute parallaxarcsecpos.parallaxfloate_PlxA[0.0008/0.004] PlxA uncertaintyarcsecstat.errorfloatpmRAA[-0.8/0.8] Absolute proper motion along RA ({mu}_{alpha},abs_cos{delta})arcsec/yrpos.pm;pos.eq.rafloate_pmRAA[0.0005/0.004] pmRAA uncertaintyarcsec/yrstat.error;pos.pm;pos.eq.rafloatpmDEA[-0.8/0.5] Absolute proper motion along DEarcsec/yrpos.pm;pos.eq.decfloate_pmDEA[0.0006/0.006] pmDEA uncertaintyarcsec/yrstat.error;pos.pm;pos.eq.decfloatChi2[4.2/29.6] The lowest {chi}^2^ in each set of MCMC chainsstat.fit.chi2;stat.minfloatdof[7/25] Degree of freedomstat.fit.dofintPhotDisplay the NIR photometry (tables 6+7) for this objectmeta.ref.urlintnullableJ/ApJ/833/96/photPhotometry and absolute magnitudes for our and other potentially young objects (tables 6 and 7)SimbadNameSimbad column added by the CDSmeta.idcharKsMag[4.2/18]? 2MASS absolute Ks-band magnitudephys.magAbsfloatnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameObject name (1)meta.id;meta.maincharprimaryn_AName[a] Flag on Name (G2)meta.notecharPlx[3.4/259.3] Parallaxmaspos.parallaxfloatn_Plx[1/55] Reference (2)meta.noteinte_Plx[0.05/5] Plx uncertaintymasstat.error;pos.parallaxfloatYmag[8.9/19]? MKO Y-band magnitudemagphot.mag;em.IR.Jfloatnullablee_Ymag[0.02/0.4]? Ymag uncertaintymagstat.error;phot.mag;em.opt.Bfloatnullablef_YmagFlag on Ymag (G1)meta.codecharJmag[8.3/20]? MKO J-band magnitudemagphot.mag;em.IR.Jfloatnullablee_Jmag[0.01/0.6]? Jmag uncertaintymagstat.error;phot.mag;em.IR.Jfloatnullablef_JmagFlag on Jmag (G1)meta.codecharHmag[7.9/20.3] MKO H-band magnitudemagphot.mag;em.IR.Hfloate_Hmag[0.01/0.3] Hmag uncertaintymagstat.error;phot.mag;em.IR.Hfloatf_HmagFlag on Hmag (G1)meta.codecharKmag[7.5/19.3]? MKO K-band magnitudemagphot.mag;em.IR.Kfloatnullablee_Kmag[0.01/0.3]? Kmag uncertaintymagstat.error;phot.mag;em.IR.Kfloatnullablef_KmagFlag on Kmag (G1)meta.codecharJmag2[8.3/20]? J-band magnitude in 2MASS systemmagphot.mag;em.IR.Jfloatnullablee_Jmag2[0.01/0.6]? Jmag2 uncertaintymagstat.error;phot.mag;em.IR.Jfloatnullablef_Jmag2Flag on Jmag2 (G1)meta.codecharHmag2[7.8/20.2] H-band magnitude in 2MASS systemmagphot.mag;em.IR.Hfloate_Hmag2[0.02/0.3] Hmag2 uncertaintymagstat.error;phot.mag;em.IR.Hfloatf_Hmag2Flag on Hmag2 (G1)meta.codecharKsmag[7.5/19.2]? Ks-band magnitude in 2MASS systemmagphot.mag;em.IR.Kfloatnullablee_Ksmag[0.01/0.3]? Ksmag uncertaintymagstat.error;phot.mag;em.IR.Kfloatnullablef_KsmagFlag on Ksmag (G1)meta.codecharW1mag[7/16.1]? AllWISE W1-band magnitudemagphot.mag;em.IR.3-4umfloatnullablee_W1mag[0.02/0.08]? W1mag uncertaintymagstat.error;phot.magfloatnullableW2mag[6.9/14.8]? AllWISE W2-band magnitudemagphot.mag;em.IR.4-8umfloatnullablee_W2mag[0.02/0.08]? W2mag uncertaintymagstat.error;phot.magfloatnullableRef1Reference(s) (see refs.dat file)meta.ref;pos.framecharOTypeGroup of object (3)meta.notecharSpTOptical spectral type (4)src.spTypecharSpTirNIR spectral type (4)src.spTypecharRef2Reference(s)meta.ref;pos.framecharYMag[6.2/17.4]? MKO absolute Y-band magnitudephys.magAbs;em.opt.Bfloatnullablee_YMag[0.04/1.2]? YMag uncertaintystat.error;pos.cartesian.yfloatnullablef_YMagFlag on Ymag (G1)meta.codecharJMag[5.4/18.4]? MKO absolute Y-band magnitudephys.magAbs;em.opt.Bfloatnullablee_JMag[0.03/1.2]? JMag uncertaintystat.errorfloatnullablef_JMagFlag on JMag (G1)meta.codecharHMag[4.7/19] MKO absolute Y-band magnitudephys.magAbs;em.opt.Bfloate_HMag[0.03/1.2] HMag uncertaintystat.errorfloatf_HMagFlag on HMag (G1)meta.codecharKMag[4.2/18.1]? MKO absolute Y-band magnitudephys.magAbs;em.opt.Bfloatnullablee_KMag[0.02/1.2]? KMag uncertaintystat.errorfloatnullablef_KMagFlag on KMag (G1)meta.codecharJMag2[5.5/18.7]? 2MASS absolute J-band magnitudephys.magAbsfloatnullablee_JMag2[0.03/1.2]? JMag2 uncertaintystat.errorfloatnullablef_JMag2Flag on JMag2 (G1)meta.codecharHMag2[4.7/19] 2MASS absolute H-band magnitudephys.magAbsfloate_HMag2[0.03/1.2] HMag2 uncertaintystat.errorfloatf_HMag2Flag on HMag2 (G1)meta.codechare_KsMag[0.02/1.2]? KsMag uncertaintystat.errorfloatnullablef_KsMagFlag on KsMag (G1)meta.codecharW1Mag[3.8/15.7]? AllWISE absolute W1 band magnitudeinstr.bandpassfloatnullablee_W1Mag[0.03/1.2]? W1Mag uncertaintystat.errorfloatnullableW2Mag[3.2/13.6]? AllWISE absolute W2 band magnitudeinstr.bandpassfloatnullablee_W2Mag[0.02/1.2]? W2Mag uncertaintystat.errorfloatnullableNotesNotes (5)meta.notecharANameComplete name as given in tables 1 and 2 (the observed sample); column added by CDSmeta.idchar2MDisplay the 2MASS data (II/246) within 2" if W1Mag is filledmeta.ref.urlcharWISEADisplay the AllWISE data (II/328) within 3"meta.ref.urlchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main