J/PASP/118/659ivo://CDS.VizieR/J/PASP/118/659doi:10.26093/cds/vizier.61180659CDSLiebert J.Gizis J.E.2025-09-09T14:13:15Z2008-04-03T21:44:48ZCDS support team

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

cds-question@unistra.frdwarf-starslate-type-starsinfrared-photometryWe report R and I band observations for 201 late M and L dwarfs selected on the basis of Two Micron All Sky Survey (Cat. II/246) JHKs and photographic red colors, made with a telescope of modest aperture. It is shown that deep surveys covering these red bands can provide data sets that complement JHKs, permitting a fairly good photometric classification system for L dwarfs. Due primarily to the disappearance of strong TiO opacities, R-I reaches a maximum at late M type and turns blueward for subtypes M9 to about L3. Apart from a small plateau at L0-L2, the I-Ks color remains as a monotonic measure of spectral type or temperature over this range, and likewise for M dwarfs. For late L types, both colors probably get redder again, although the accuracy of our data and number of objects do not give us robust conclusions by L6-L8. It is also interesting to look at the dispersions of the IJKs bands at a given spectral type. It is widely believed that this dispersion is caused by object-to-object variations in the amount, location, or other properties of dust or clouds. We find a moderately larger spread for the J-Ks color than for I-J.2006PASP..118..659Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/PASP/118/659CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/126/2421 : 2MASS-Selected sample of ultracool dwarfs (Cruz+, 2003)J/AJ/132/891 : Binaries among nearby L dwarfs (Reid+, 2006)J/AJ/133/439 : Luminosity function of M7-L8 ultracool dwarfs (Cruz+, 2007)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/PASP/118/659https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/PASP/118/659http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/PASP/118/659https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/PASP/118/659https://vizier.iucaa.in/viz-bin/votable?-source=J/PASP/118/659http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/PASP/118/659GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/PASP/118/659/table1 (*Observed Sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/PASP/118/659/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/PASP/118/659/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/PASP/118/659/table1?GETtext/xml+votable180.050000true0.1195-12.75430560.0055555555555555566/4253 4719 4775 8374 8393 8473 8487 8735 8761 16410 16528 16737 16766 16850 17074 17096 17105 17203 17283 17297 17303 17309 17698 17712 18060 18065 18567 18571 18726 18741 19008 19857 24682 24757-24758 24772 24792 24815 24835 24846 24871 24887 24891 24912 24917 24919 24969 24982 25015 25078 25117 25160 25162 25165 25182 25188 25200 25223 25245 25271 25275 25314 25384 25386 25470 25559 25616 25619 25638 25656 25672 25674 26017 26020 26022 26130 26170 26193 26217 26249 26279 26646 26661 26738 26758 26861 26909 26915 26918 26945 26951 26953 26966 26968 26982 26986 27011 27014 27019 27206 27618 27635 27855 27911 28178 28191 28222 28240 28257 32426 33767 34660 35630 35725 35731 35943 35951 36391 36411 36458 36502 36601 36640 36822 36845 38891 38898 38905 40276 40313 40946 43957 44014 44018-44019 44021 44025 44226 44684 44718-44719 44728 44778 44807 46322 46334 46671 46680 46846 46961 46971 47034 48304 48317-48318 48365 48390 48409 48432 48462 48516 48546 48560 48593 48684-48685 48687 48723 48755 48786-48787 48793 48796 48798-48799 48840 48990 48995 49026 490681.1166583743361574e-19 1.7003137259100215e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/PASP/118/659?format=asciiInfrareddefaultJ/PASP/118/659/table1*Observed SamplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainRcmag? Cousins R magnitudemagphot.mag;em.opt.Rfloatnullablee_Rcmag? rms uncertainty on Rcmagmagstat.error;phot.mag;em.opt.RfloatnullableIcmag? Cousins I magnitudemagphot.mag;em.opt.Ifloatnullablee_Icmag? rms uncertainty on Icmagmagstat.error;phot.mag;em.opt.IfloatnullableRc-Ic? Cousins R-I colour indexmagphot.color;em.opt.R;em.opt.IfloatnullableJmag2MASS J magnitudemagphot.mag;em.IR.JfloatHmag2MASS H magnitudemagphot.mag;em.IR.HfloatKs2MASS Ks magnitudemagphot.mag;em.IR.KfloatSpTypeMK spectral typesrc.spTypechare_SpType? Error on SpTypestat.error;src.spTypefloatnullabler_SpType? Reference for SpType (1)meta.ref;pos.frameintnullable2MASSDisplay the 2MASS data (Cat. II/246)meta.ref.urlchar