J/MNRAS/430/1171ivo://CDS.VizieR/J/MNRAS/430/1171doi:10.26093/cds/vizier.74301171CDSDay-Jones A.C.Marocco F.Pinfield D.J.Zhang Z.H.Burningham B.,Deacon N.Ruiz M.T.Gallardo J.Jones H.R.A.Lucas P.W.L.,Jenkins J.S.Gomes J.Folkes S.L.Clarke J.R.A.2024-07-20T20:14:06Z2014-05-16T14:43:04ZCDS support team

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

cds-question@unistra.frlate-type-starsyoung-stellar-objectsphotometryspectroscopyWe present a new sample of mid-L to mid-T dwarfs with effective temperatures of 1100-1700K selected from the UKIDSS Large Area Survey (LAS) and confirmed with infrared spectra from X-shooter/Very Large Telescope. This effective temperature range is especially sensitive to the formation history of Galactic brown dwarfs and allows us to constrain the form of the sub-stellar birth rate, with sensitivity to differentiate between a flat (stellar like) birth rate and an exponentially declining form. We present the discovery of 63 new L and T dwarfs from the UKIDSS LAS DR7, including the identification of 12 likely unresolved binaries, which form the first complete sub-set from our programme, covering 495 square degrees of sky, complete to J=18.1. We compare our results for this sub-sample with simulations of differing birth rates for objects of masses 0.10-0.03M_{sun}_ and ages 1-10Gyr. We find that the more extreme birth rates (e.g. a halo type form) can likely be excluded as the true form of the birth rate. In addition, we find that although there is substantial scatter we find a preference for a mass function, with a power-law index {alpha} in the range -1<{alpha}<0 that is consistent (within the errors) with the studies of late T dwarfs.2013MNRAS.430.1171Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/430/1171CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012)II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/430/1171https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/430/1171http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/430/1171https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/430/1171https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/430/1171http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/430/1171GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/430/1171/table1 (Photometry of a sub-sample of brown dwarfs)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/430/1171/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/430/1171/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/430/1171/table1?GETtext/xml+votable180.050000true1.5541715.67250.0055555555555555566/22 48 56 64-66 550 17663 17746 17811 17814 17826 17901 17997 18024 18065 18084 18092 18225 18229 18245 18300 18303 18312 18383 18387-18389 18409 18411 18770 18792-18793 18797 18837 18844 18853 18858 18860 18862 18881 18933 19021 19047 19052 19200 19253 19269-19270 19273 19278 19280 19515 19583 19678 19727 19733 19747 19752 19754-19755 19761 19987-19988 19992 19995-19996 20000-20001 23269 23273-23274 232781.489977759996881e-19 1.692669228152603e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/430/1171?format=asciiOpticaldefaultJ/MNRAS/430/1171/table1Photometry of a sub-sample of brown dwarfsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameName of brown dwarfmeta.id;meta.maincharr_NameDiscovery reference (1)meta.ref;pos.framecharBRLT[1/344]? BRLT numbermeta.idintnullableRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainJmagUKIDSS J magnitude (2)magphot.mag;em.IR.JfloatY-JUKIDSS Y-J colour index (2)magphot.color;em.opt;em.IRfloatJ-HUKIDSS J-H colour index (2)magphot.color;em.IR.J;em.IR.HfloatJ-K? UKIDSS J-K colour index (2)magphot.color;em.IR.J;em.IR.Kfloatnullablez-J? UKIDSS-SDSS z-J colour index (2)magphot.color;em.opt;em.IRfloatnullablei-z? UKIDSS-SDSS i-z colour index (2)magphot.color;em.opt.I;em.opt.IfloatnullableSimbadNameSimbad column added by the CDSmeta.idcharJ/MNRAS/430/1171/table4Spectral details of observed targetsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBRLT[1/344] BRTL numbermeta.idintprimarySpTMK spectral typesrc.spTypechare_SpTrms uncertainty on SpTypestat.errorfloatH2O-JH_2_O-J binary index (1)spect.indexfloatH2O-HH_2_O-H binary index (1)spect.indexfloatH2O-KH_2_O-K binary index (1)spect.indexfloatCH4-JCH_4_-J binary index (1)spect.indexfloatCH4-HCH_4_-H binary index (1)spect.indexfloatCH4-KCH_4_-K binary index (1)spect.indexfloatK/JK/J binary index (1)spect.indexfloatH-dipH-dip binary index (1)spect.indexfloatNote[SC WC] Notes (2)meta.notechar