J/ApJS/281/49ivo://CDS.VizieR/J/ApJS/281/49CDSTu Z.Wang S.Chen X.Liu J.2026-08-12T12:09:11Z2026-08-12T12:39:51ZCDS support team

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

cds-question@unistra.frbrown-dwarfsinfrared-astronomyspectroscopystellar-spectral-typeschemical-abundancesextinctionstellar-agesstellar-massesstellar-radiistellar-distancestellar-evolutionary-modelsBrown dwarfs are essential probes of stellar and planetary formation, yet their low luminosities pose challenges for detection at large Galactic distances. The James Webb Space Telescope (JWST), with its unprecedented near-infrared sensitivity, enables the discovery and characterization of distant substellar objects, including those in the Milky Way's thick disk and halo. We conducted a systematic search using over 40,000 publicly available JWST/NIRSpec PRISM/CLEAR spectra and identified 68 brown dwarfs through spectral template matching and visual inspection. Among them, 12 are newly identified candidates, including eight T dwarfs and four M/L dwarfs, most at distances exceeding 1 kpc. Remarkably, two sources-JWST J001418.22-302223.2 and JWST J033240.07-274907.8-are found at distances greater than 5kpc, making them the most distant brown dwarfs within the Milky Way. Spectral fits were performed using a nested sampling Monte Carlo algorithm with three model grids: Sonora Elf Owl, LOWZ, and SAND. The analysis reveals that cloud-free models are unable to reproduce L/T transition spectra, whereas the SAND model provides a more accurate representation of cloud effects in metal-poor environments. With the newly identified distant brown dwarfs, we also investigated the vertical metallicity gradient of brown dwarfs. Overall, the metallicities do not show an evident trend with Galactic height |Z|, due to the limited sample size and the uncertainties in metallicity measurements.2025ApJS..281...49Thttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/281/49CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toV/159 : JADES NIRCam & NIRSpec cat. (DR1-DR3) (Rieke+, 2023)J/ApJ/637/1067 : NIR spectral classification of T dwarfs (Burgasser+, 2006)J/ApJS/190/100 : NIR proper motion survey using 2MASS (Kirkpatrick+, 2010)J/ApJS/197/19 : First brown dwarfs discovered by WISE (Kirkpatrick+, 2011)J/ApJ/753/156 : T/Y brown dwarfs with WISE photometry (Kirkpatrick+, 2012)J/MNRAS/433/457 : 76 T dwarfs from the UKIDSS LAS (Burningham+, 2013)J/ApJS/205/6 : T dwarf population revealed by WISE (Mace+, 2013)J/PASP/125/809 : New nearby M, L, and T dwarfs (Thompson+, 2013)J/ApJ/782/8 : Spectroscopy of 104 objects in the ONC (Ingraham+, 2014)J/ApJ/814/118 : L/T dwarfs search with PS1 & WISE. II. (Best+, 2015)J/ApJS/225/10 : Kinematic analysis of M7-L8 dwarfs (Faherty+, 2016)J/ApJ/889/74 : Spitzer follow-up of Y brown dwarfs (Meisner+, 2020)J/ApJ/946/43 : Sp. RSG stars in the MCs from APOGEE & Gaia (Wang+, 2023)J/AJ/168/230 : Phot. of substellar cand. in ONC with JWST (Luhman, 2024)J/ApJ/975/162 : Sp. of brown dwarf cand. in ONC from JWST (Luhman+, 2024)J/AJ/167/5 : WISE J085510.83-071442.5 sp. with JWST (Luhman+, 2024)J/AJ/167/168 : NIRSpec sp. of TWA 28, TWA 27A & TWA 27B (Manjavacas+, 2024)J/A+A/691/A240 : ASTRODEEP-JWST photometry and redshifts (Merlin+, 2024)J/ApJS/270/7 : UNCOVER phot. cat. of A2744 with HST+JWST (Weaver+, 2024)J/MNRAS/542/L126 : Spectra of brown dwarf candidates in the ONC (Luhman, 2025)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/281/49https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/281/49http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/281/49https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/281/49https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/281/49http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/281/49GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/281/49/table4 (Brown dwarf derived parameters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/281/49/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/281/49/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/281/49/table4?GETtext/xml+votable180.050000true3.5759167-30.37311110.0055555555555555566/1006 1539 1825 3764 3946 5024 6044 6804 8109 11425 11435 12223 12519 12644 13446 16486 17690 19467 21439 23471 26020 26555 27541 31319 32580 33031 33192 33257 34304 35935 37404 38973 40905 40924 42270 44033 44270 44338 46070 46617 47940https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/281/49?format=asciiInfrareddefaultJ/ApJS/281/49/table4Brown dwarf derived parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharm_NameNumber of evolutionary model used for the measurements of this brown dwarfmeta.numberintnullableSpTSpectral type (1)src.spTypecharr_SpT[0/26]? Spectral type Reference (0=This work) (2)meta.ref;src.spTypeintnullableModelEvolutionary modelstat.param;meta.modelledcharf_ModelFlag on Model (3)meta.codecharTeff[297/3004] Effective temperatureKphys.temperature.effectiveintE_Teff[12/345] Upper uncertainty in TeffKstat.error;stat.max;phys.temperature.effectiveinte_Teff[12/285] Lower uncertainty in TeffKstat.error;stat.min;phys.temperature.effectiveintlog(g)[2.89/6.0] Log of surface gravitylog(cm.s**-2)phys.gravityfloatE_log(g)[0.13/1.75] Upper uncertainty in log(g)log(cm.s**-2)stat.error;stat.max;phys.gravityfloate_log(g)[0.13/0.88] Lower uncertainty in log(g)log(cm.s**-2)stat.error;stat.min;phys.gravityfloatf_log(g)Flag on log(g) (4)meta.codechar[M/H][-2.04/0.98] Metallicityphys.abund.ZfloatE_[M/H][0.1/0.38] Upper uncertainty in [M/H]stat.error;stat.max;phys.abund.Zfloate_[M/H][0.1/0.4] Lower uncertainty in [M/H]stat.error;stat.min;phys.abund.ZfloatC/O[0.22/0.85]? Carbon-to-oxygen ratiophys.abund;arith.ratiofloatnullableE_C/O[0.11/0.25]? Upper uncertainty in C/Ostat.error;stat.max;phys.abundfloatnullablee_C/O[0.11/0.24]? Lower uncertainty in C/Ostat.error;stat.min;phys.abundfloatnullablelog(K)[1.98/9.92]? Eddy diffusion parameterlog(cm**2.s**-1)stat.fit.paramfloatnullableE_log(K)[0.52/6.12]? Upper uncertainty in log(K)log(cm**2.s**-1)stat.error;stat.max;stat.fit.paramfloatnullablee_log(K)[0.52/4.2]? Lower uncertainty in log(K)log(cm**2.s**-1)stat.error;stat.min;stat.fit.paramfloatnullablea/Fe[-0.03/0.4]? Value of {alpha} enhancementphys.abund;arith.ratiofloatnullableE_a/Fe[0.03/0.3]? Upper uncertainty in a/Festat.error;stat.max;phys.abundfloatnullablee_a/Fe[0.03/0.11]? Lower uncertainty in a/Festat.error;stat.min;phys.abundfloatnullableAv[1.93/7.83]? Extinctionmagphys.absorptionfloatnullableE_Av[0.02/1.38]? Upper uncertainty in Avmagstat.error;stat.max;phys.absorptionfloatnullableE_Rad[0.01/4.52] Upper uncertainty in Rad(7.1492x10+7m)stat.error;stat.max;phys.size.radiusfloate_Rad[0.01/2.12] Lower uncertainty in Rad(7.1492x10+7m)stat.error;stat.min;phys.size.radiusfloatf_RadFlag on Rad (6)meta.codecharDist[4/15874] Distance (7)pcpos.distanceintE_Dist[1/6706] Upper uncertainty in Distpcstat.error;stat.max;pos.distanceinte_Dist[1/6367] Lower uncertainty in Distpcstat.error;stat.min;pos.distanceintSimbadNameSimbad column added by the CDSmeta.idcharnullable_RAPositions from SIMBAD or JWST names (right ascension part)degpos.eq.ra;meta.main_DEPositions from SIMBAD or JWST names (declination part)degpos.eq.dec;meta.maine_Av[0.03/0.54]? Lower uncertainty in Avmagstat.error;stat.min;phys.absorptionfloatnullablelog(R2/D2)[-24.93/-18.46] Log of scale factorarith.factorfloatE_log(R2/D2)[0.05/0.2] Upper uncertainty in log(R2/D2)stat.error;stat.max;arith.factorfloate_log(R2/D2)[0.05/0.2] Lower uncertainty in log(R2/D2)stat.error;stat.min;arith.factorfloatlog(f)[-18.49/-11.51] Log of jitter termstat.fit.paramfloatE_log(f)[0.01/0.72] Upper uncertainty in log(f)stat.error;stat.max;stat.fit.paramfloate_log(f)[0.01/1.79] Lower uncertainty in log(f)stat.error;stat.min;stat.fit.paramfloatchi2[1.1/117339.1] Reduced {chi}-squaredstat.fit.chi2doubleAge[0.001/10] Stellar age (5)Gyrtime.agefloatE_Age[0.001/6.7] Upper uncertainty in AgeGyrstat.error;stat.max;time.agefloate_Age[0.001/8.4] Lower uncertainty in AgeGyrstat.error;stat.min;time.agefloatf_AgeFlag on Age (6)meta.codecharMass[1.0/78.6] Mass (5)(1.898187x10+27kg)phys.massfloatE_Mass[0.1/57.6] Upper uncertainty in Mass(1.898187x10+27kg)stat.error;stat.max;phys.massfloate_Mass[0.1/26.9] Lower uncertainty in Mass(1.898187x10+27kg)stat.error;stat.min;phys.massfloatf_MassFlag on Mass (6)meta.codecharRad[0.76/7.92] Radius (5)(7.1492x10+7m)phys.size.radiusfloat