J/ApJ/752/56ivo://CDS.VizieR/J/ApJ/752/56doi:10.26093/cds/vizier.17520056CDSFaherty J.K.Burgasser A.J.Walter F.M.Van der Bliek N.Shara M.M.,Cruz K.L.West A.A.Vrba F.J.Anglada-Escude G.2026-01-20T12:12:45Z2014-02-24T13:18:20ZCDS support team

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

cds-question@unistra.frastrometryvisible-astronomytrigonometric-parallaxsloan-photometryinfrared-photometrystellar-spectral-typesproper-motionsWe report parallax measurements for 70 ultracool dwarfs (UCDs) including 11 late-M, 32 L, and 27 T dwarfs. In this sample, 14 M and L dwarfs exhibit low surface gravity features, 6 are close binary systems, and 2 are metal-poor subdwarfs. We combined our new measurements with 114 previously published UCD parallaxes and optical-mid-IR photometry to examine trends in spectral-type/absolute magnitude, and color-color diagrams. We report new polynomial relations between spectral type and M_JHK_. Including resolved L/T transition binaries in the relations, we find no reason to differentiate between a "bright" (unresolved binary) and a "faint" (single source) sample across the L/T boundary. Isolating early T dwarfs, we find that the brightening of T0-T4 sources is prominent in M_J_ where there is a [1.2-1.4] mag difference. A similar yet dampened brightening of [0.3-0.5] mag happens at M_H_ and a plateau or dimming of [-0.2 to -0.3] mag is seen in M_K_. Comparison with evolutionary models that vary gravity, metallicity, and cloud thickness verifies that for L into T dwarfs, decreasing cloud thickness reproduces brown dwarf near-IR color-magnitude diagrams. However we find that a near constant temperature of 1200 +/-100 K along a narrow spectral subtype of T0-T4 is required to account for the brightening and color-magnitude diagram of the L-dwarf/T-dwarf transition. There is a significant population of both L and T dwarfs which are red or potentially "ultra-cloudy" compared to the models, many of which are known to be young indicating a correlation between enhanced photospheric dust and youth. For the low surface gravity or young companion L dwarfs we find that 8 out of 10 are at least [0.2-1.0] mag underluminous in M_JH_and/or M_K_compared to equivalent spectral type objects. We speculate that this is a consequence of increased dust opacity and conclude that low surface gravity L dwarfs require a completely new spectral-type/absolute magnitude polynomial for analysis.2012ApJ...752...56Fhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/752/56CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)J/A+A/556/A133 : Low-mass companion to ultracool dwarf orbit (Sahlmann+, 2013)J/ApJ/746/23 : Radio observations of ultracool dwarf stars (McLean+, 2012)J/ApJS/201/19 : Hawaii Infrared Parallax Program. I. (Dupuy+, 2012)J/ApJS/197/19 : First brown dwarfs discovered by WISE (Kirkpatrick+, 2011)J/A+A/512/A37 : Velocities of 43 nearby L dwarfs (Seifahrt+, 2010)J/AJ/139/1808 : Colors and kinematics of SDSS L dwarfs (Schmidt+, 2010)J/A+A/497/619 : New ultra-cool dwarfs from SDSS and 2MASS (Zhang+, 2009)J/A+A/493/L27 : Parallaxes of 10 ultracool subdwarfs (Schilbach+, 2009)J/AJ/137/1 : Paper I - Late-type dwarfs astrometry (Faherty+, 2009)J/AJ/136/1290 : Ultracool dwarfs from the 2MASS (Reid+, 2008)J/ApJ/689/1295 : Li test implications for brown dwarfs (Kirkpatrick+, 2008)J/AJ/134/1162 : 11 new T dwarfs in 2MASS (Looper+, 2007)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/ApJ/637/1067 : Near-IR spectral classification of T dwarfs (Burgasser+, 2006)J/AJ/127/2856 : Brown dwarfs in the 2MASS Survey (Burgasser+, 2004)J/AJ/127/3553 : JHK phot. and spectroscopy for L and T dwarfs (Knapp+, 2004)J/AJ/126/2421 : 2MASS-Selected sample of ultracool dwarfs (Cruz+, 2003)J/AJ/126/2487 : T dwarfs in the southern hemisphere (Burgasser+, 2003)J/AJ/125/1598 : New high PM stars in the northern sky (Lepine+, 2003)J/AJ/123/3409 : SDSS M, L, and T dwarfs (Hawley+, 2002)J/ApJ/564/421 : Spectra of T dwarfs. I. (Burgasser+, 2002)J/ApJ/476/311 : 2MASS M-dwarf discoveries (Kirkpatrick+ 1997)J/AJ/103/638 : USNO Photographic Parallaxes. I. (Monet+, 1992)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/752/56https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/752/56http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/752/56https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/752/56https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/752/56http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/752/56GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/752/56/targets (Astrometry of targets (tables 1 and 2))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/752/56/targets?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/752/56/targets?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/752/56/targets?GETtext/xml+votable180.050000true8.2326981-44.08493440.005555555555555556Cone search capability for table J/ApJ/752/56/table5 (*Photometry of full sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/752/56/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/752/56/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/752/56/table5?GETtext/xml+votable180.050000true1.14528-40.73512890.0055555555555555566/439 496 858 2789 3965 4253 4316 4719 4775 4783 4948 5413 5659 5718 6328 6613 6766 8223 8299 8361 8625 8783 8794 8995 9072 9467 9569 9597 10243 10718 11719 11862 11940 12066 12541 12579 12592 13122 14850 15494 16546 16873 17166 17814 18017 18032 18067 18156 18300 18683 18840 18860 19050 19747 19813 19857 19912 20591 20896 20993 20996 21093 21296 21480 21729 21856 21861 21880 22521 22681 22759 22810 22861 22937 23274 23533 24590 24605 24694 24716 25015 25052 25100 25314 25443 25934-25935 25945 26020 26186 26196 26210 26248 26403 26514 26555 26564 26667 26861 27201 27382 27395 27402 27414 27514 27536 27653 27698 27798 27975 28277 28344 30749 30956 31011 31062 31268 31309 31319 31411 31549 31714 31992 32337 32426 32457 33351 33655 33767 34660 34780 35387 35499 35906 36072 36418 36602 37267 37502 37565 38382 38472 38683 38786 38812 38915 38966 39044 39109 39482 39485 39683 40191 40228 40397 40738 40882 40901 40947 42739 43422 43856 43966 44118 44286 44632 44807 44954 45332 45564 45752 46334 46607 47192 47640 48907 49077 491392.0616683193919197e-20 3.5010283109654867e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/752/56?format=asciiOpticalInfrareddefaultJ/ApJ/752/56/targetsAstrometry of targets (tables 1 and 2)NameSource namemeta.id;meta.mainchar_RAPositions from SIMBAD database (right ascension part)degpos.eq.ra;meta.mainrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSpT.oOptical MK spectral type (G2)src.spTypeSpT.iNIR optical MK spectral typesrc.spTypecharNobs[5/25] Number of observing nightsmeta.numberintNf[11/91] Number of frames used in the parallax solutionmeta.numberintNr[21/99] Number of reference stars used in the parallax solutionmeta.numberintDt[1/4] Time of observing in years ({Delta}t)yrtime.intervalfloatJmag[10.1/17.1] MKO J-band magnitudemagphot.mag;em.IR.Jfloate_Jmag[0.02/0.2] Jmag uncertaintymagstat.error;phot.magfloatInstInstrument code (1)meta.code;instrcharNoteNote (G1)meta.notecharFlagLarge uncertainties (2)meta.code.errorcharRefReference(s) (see refs.dat file)meta.ref;pos.framechar2MDisplay the 2MASS data (Cutri et al. 2003, Cat. II/246) within 2"meta.ref.urlcharSpTFinal MK spectral type (G2)src.spTypePlxR[18/195] Relative parallaxmaspos.parallax.trigfloate_PlxR[2/15] PlxR uncertaintymasstat.errorfloatPlx[19/196] Final parallax with absolute corrections (section 3.3)maspos.parallax.trigfloate_Plx[2/15] PlxA uncertaintymasstat.error;pos.parallaxfloatpmRA[-2928/2330] Proper motion along RAmas/yrpos.pm;pos.eq.rafloate_pmRA[2/13] pmRA uncertaintymas/yrstat.error;pos.pm;pos.eq.rafloatpmDE[-1954/1644] Proper motion along DEmas/yrpos.pm;pos.eq.decfloate_pmDE[2/13] pmDE uncertaintymas/yrstat.error;pos.pm;pos.eq.decfloatVtan[2/312] Tangential velocitykm/sphys.veloc.transversefloate_Vtan[0.3/46] Vtan uncertaintykm/sstat.errorfloatF09Cross-match with Faherty et al., 2009, Cat. J/AJ/137/1, within 2"meta.ref.urlintnullable_DEPositions from SIMBAD database (declination part)degpos.eq.dec;meta.mainSimbadNameSimbad column added by the CDSmeta.idnullableJ/ApJ/752/56/table5*Photometry of full samplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameSource namemeta.id;meta.maincharprimaryRefReference(s) (see refs.dat file)meta.ref;pos.framecharF09Cross-match with Faherty et al., 2009, Cat. J/AJ/137/1, within 2"meta.ref.urlintnullableSEDSED plot of this starmeta.ref.urlchar2MDisplay the 2MASS data (Cutri et al. 2003, Cat. II/246) within 2"meta.ref.urlchar_RAPositions from SIMBAD database (right ascension part)degpos.eq.ra;meta.main_DEPositions from SIMBAD database (declination part)degpos.eq.dec;meta.mainTmeta.ref.urlcharSpT.oOptical MK spectral type (G2)src.spTypeSpT.iNear-IR MK spectral typesrc.spTypecharPlx[9.8/276] Parallaxmaspos.parallax.trigfloate_Plx[0.3/33] Uncertainty in Plxmasstat.error;pos.parallaxfloatrmag[18.6/26]? SDSS r band magnitudemagphot.mag;em.opt.Rfloatnullablee_rmag[0.01/0.9]? Uncertainty in rmagmagstat.error;phot.magfloatnullableimag? SDSS i band magnitudemagphot.mag;em.opt.Ifloatnullablee_imag? Uncertainty in imagmagstat.error;phot.magfloatnullablezmag? SDSS z band magnitudemagphot.mag;em.opt.Ifloatnullablee_zmag? Uncertainty in zmagmagstat.error;phot.magfloatnullableYmag[12.8/20]? MKO Y band magnitudemagphot.mag;em.IR.Jfloatnullablee_Ymag[0.02/0.2]? Uncertainty in Ymagmagstat.error;phot.magfloatnullableLmag? MKO L band magnitudemagphot.mag;em.IR.3-4umfloatnullablee_Lmag? Uncertainty in Lmagmagstat.error;phot.magfloatnullableMmag? MKO M band magnitudemagphot.mag;em.IR.4-8umfloatnullablee_Mmag? Uncertainty in Mmagmagstat.error;phot.magfloatnullableJmag[11.3/19] MKO J band magnitudemagphot.mag;em.IR.Jfloate_Jmag[0/1.2] Uncertainty in Jmagmagstat.error;phot.magfloatHmagMKO H band magnitudemagphot.mag;em.IR.Hfloate_HmagUncertainty in Hmagmagstat.error;phot.magfloatKmag[10/20] MKO K band magnitudemagphot.mag;em.IR.Kfloate_Kmag[0/0.5] Uncertainty in Kmagmagstat.error;phot.magfloat[3.6][9.8/16]? Spitzer/IRAC 3.6 micron band magnitudemagphot.mag;em.IR.3-4umfloatnullablee_[3.6][0.01/0.06]? Uncertainty in [3.6]magstat.errorfloatnullable[4.5]? Spitzer/IRAC 4.5 micron band magnitudemagphot.mag;em.IR.4-8umfloatnullablee_[4.5]? Uncertainty in [4.5]magstat.errorfloatnullable[5.8]? Spitzer/IRAC 5.8 micron band magnitudemagphot.flux.density;em.IR.4-8umfloatnullablee_[5.8]? Uncertainty in [5.8]magstat.errorfloatnullable[8.0][8.9/14.3]? Spitzer/IRAC 8.0um band magnitudemagphot.flux.density;em.IR.8-15umfloatnullablee_[8.0][0/0.3]? Uncertainty in [8.0]magstat.errorfloatnullableNoteSource note (G1)meta.notecharSimbadNameSimbad column added by the CDSmeta.idnullableJ/ApJ/752/56/refsReferencesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRefReference codemeta.noteintBibCodeBibcodemeta.bib.bibcodecharAutAuthor's name(s)meta.bib.authorcharCommCommentmeta.notechar