J/ApJ/541/977ivo://CDS.VizieR/J/ApJ/541/977doi:10.26093/cds/vizier.15410977CDSNajita J.R.Tiede G.P.Carr J.S.2004-06-05T22:02:59Z2004-06-05T22:02:16ZCDS support team

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

cds-question@unistra.fropen-star-clusterslate-type-starsmorgan-keenan-classificationinfrared-photometryWe investigate the low-mass population of the young cluster IC 348 down to the deuterium-burning limit, a fiducial boundary between brown dwarf and planetary mass objects, using a new and innovative method for the spectral classification of late-type objects. Using photometric indices, constructed from HST/NICMOS narrowband imaging, that measure the strength of the 1.9{mu}m water band, we determine the spectral type and reddening for every M-type star in the field, thereby separating cluster members from the interloper population. Due to the efficiency of our spectral classification technique, our study is complete from ~0.7 to 0.015M_{sun}_. The mass function derived for the cluster in this interval, dN/dlogM{prop.to}M^0.5^, is similar to that obtained for the Pleiades, but appears significantly more abundant in brown dwarfs than the mass function for companions to nearby Sunlike stars. This provides compelling observational evidence for different formation and evolutionary histories for substellar objects formed in isolation versus as companions. Because our determination of the IMF is complete to very low masses, we can place interesting constraints on the role of physical processes such as fragmentation in the star and planet formation process and the fraction of dark matter in the Galactic halo that resides in substellar objects.2000ApJ...541..977Nhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/541/977CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/541/977https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/541/977http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/541/977https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/541/977https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/541/977http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/541/977GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/541/977/table4 (Data for objects in the IC 348a fields)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/541/977/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/541/977/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/541/977/table4?GETtext/xml+votable180.050000true56.158958332.17230560.005555555555555556HST6/1539https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/541/977?format=asciiOpticalInfrareddefaultJ/ApJ/541/977/table1Standard StarsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameObject name (J1-4423 = [HJS91] 4423)meta.id;meta.maincharSpTypeMK spectral type (1)src.spTypecharKmag? K magnitude (2)magphot.mag;em.IR.KfloatnullableAV? Absorption in V bandmagphys.absorptionfloatnullableF166F166N flux, centered on 1.66{mu}mJyphot.flux.density;em.IR.Hdoublee_F166rms uncertainty on F166Jystat.errordoubleF190F190N flux, centered on 1.90{mu}mJyphot.flux.density;em.IRdoublee_F190rms uncertainty on F190Jystat.errordoubleF215F215N flux, centered on 2.15{mu}mJyphot.mag;em.IR.Kdoublee_F215rms uncertainty on F215Jystat.errordoubleNotes[c-k ] Individual notes (3)meta.notecharJ/ApJ/541/977/table4Data for objects in the IC 348a fieldsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNTCSequential number, FFF-NN (Cl* IC 348 NTC FFFNN in Simbad)meta.id;meta.maincharNote[e] Note on observations (1)meta.notecharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainLRL? Luhman et al., 1998ApJ...508..347L, number Cl* IC 348 LRL NNN in Simbadmeta.idintnullableL99? Luhman et al., 1999, Cat. <J/ApJ/525/466>, number Cl* IC 348 LRL NNN in Simbadmeta.idintnullableH98? Herbig et al., 1998, Cat. <J/ApJ/497/736> number, Cl* IC 348 H NNN in Simbadmeta.idintnullableF166F166N flux, centered on 1.66{mu}mmJyphot.flux.density;em.IR.Hfloate_F166rms uncertainty n F166mJystat.errorfloatF190F190N flux, centered on 1.90{mu}mmJyphot.flux.density;em.IRfloate_F190rms uncertainty n F190mJystat.errorfloatF215F215N flux, centered on 2.15{mu}mmJyphot.mag;em.IR.Kfloate_F215rms uncertainty n F215mJystat.errorfloatQH2OReddening-independent water index (2)phot.colorfloate_QH2Orms uncertainty on QH2Ostat.errorfloatAKAbsorption in K bandmagphys.absorptionfloate_AKrms uncertainty on AKmagstat.errorfloatKmagK magnitude (3)magphot.mag;em.IR.Kfloate_Kmagrms uncertainty on Kmagmagstat.errorfloatl_SpType[<= >] Limit flag on SpTypemeta.code.errorcharSpTypeSpectral typesrc.spTypechare_SpType? rms uncertainty on spectral subtype (4)stat.errorfloatnullablen_SpType[fg] Spectral type determination (5)meta.notecharJ/ApJ/541/977/table6Objects with separations of less than 8"recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintPrimPrimary namemeta.id;meta.maincharSecondSecondary namemeta.id.assoccharSepSeparationarcsecpos.angDistancefloatK01Dereddened K magnitude of the primarymagphot.mag;em.IR.KfloatK02Dereddened K magnitude of the secondarymagphot.mag;em.IR.KfloatSpType1Spectral type of the primarysrc.spTypecharSpType2Spectral type of the secondarysrc.spTypecharAK1Absorption in K band of the primarymagphys.absorptionfloatAK2Absorption in K band of the secondarymagphys.absorptionfloatIDIdentification letter in fig. 14meta.codechar