J/ApJ/706/1484ivo://CDS.VizieR/J/ApJ/706/1484doi:10.26093/cds/vizier.17061484CDSBoudreault S.Bailer-Jones C.A.L.2026-05-19T14:25:37Z2012-02-02T13:18:46ZCDS support team

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

cds-question@unistra.fropen-star-clustersphotometryspectroscopyradial-velocitym-starsstellar-masseseffective-temperaturestellar-spectral-typesline-intensitiesWe present the stellar and substellar mass function (MF) of the open cluster IC 2391, plus its radial dependence, and use this to put constraints on the formation mechanism of brown dwarfs (BDs). Our multi-band optical and infrared photometric survey with spectroscopic follow-up covers 11deg^2^, making it the largest survey of this cluster to date. From our preliminary spectroscopic follow-up, to confirm BD status and cluster membership, we find that all candidates are M dwarfs (in either the field or the cluster), demonstrating the efficiency of our photometric selection method in avoiding contaminants (e.g., red giants). About half of our photometric candidates for which we have spectra are spectroscopically confirmed as cluster members; two are new spectroscopically confirmed BD members of IC 2391.2009ApJ...706.1484Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/706/1484CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/501/553 : Equivalent widths of IC 2602 + IC 2391 stars (D'Orazi+, 2009)J/A+A/461/509 : Membership and spectroscopy of IC 2391 (Platais+, 2007)J/A+A/468/151 : Nearby open clusters radii and masses (Piskunov+, 2007)J/A+A/430/287 : XMM observations of IC 2391 stars (Marino+, 2005)J/MNRAS/355/959 : Proper motions of IC 2391 possible members (Dodd+, 2004)J/A+A/372/862 : Lithium abundances in IC 2602 and IC 2391 (Randich+, 2001)J/ApJS/134/103 : Low-mass members of IC 2391 (Barrado y Navascues+, 2001)J/A+A/345/471 : Memberships of open clusters (Robichon+, 1999)J/A+AS/126/357 : Members of IC 2391 (Rolleston+ 1997)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/706/1484https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/706/1484http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/706/1484https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/706/1484https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/706/1484http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/706/1484GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/706/1484/table2 (All photometric candidates of our survey)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/706/1484/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/706/1484/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/706/1484/table2?GETtext/xml+votable180.050000true126.56689583-51.047866670.005555555555555556Cone search capability for table J/ApJ/706/1484/table3 (Photometric candidates already detected by previous studies (table corrected by the author))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/706/1484/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/706/1484/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/706/1484/table3?GETtext/xml+votable180.050000true129.69614167-52.248933330.005555555555555556Cone search capability for table J/ApJ/706/1484/spectro (Stellar parameters and other data for the spectroscopic follow-up sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/706/1484/spectro?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/706/1484/spectro?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/706/1484/spectro?GETtext/xml+votable180.050000true129.16817917-53.358333330.0055555555555555565/9445-9447 9453-9454 6/37777-37779 37809-37811 37820 37824 378261.398457827073138e-19 2.6706780932288093e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/706/1484?format=asciiOpticaldefaultJ/ApJ/706/1484/table2All photometric candidates of our surveyrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFieldField numbermeta.id;obs.fieldintIDRunning identification numbermeta.id;meta.mainintn_IDSimbad column added by the CDSmeta.ref.urlcharRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainRmag? Observed WFI R_c_ band magnitudemagphot.mag;em.opt.RfloatnullableO770/19? Observed 770/19 medium band magnitude (G1)magphot.mag;em.opt.IfloatnullableO815/20Observed 815/20 medium band magnitude (G1)magphot.mag;em.opt.IfloatO856/14? Observed 856/14 medium band magnitude (G1)magphot.mag;em.opt.IfloatnullableO914/27Observed 914/27 medium band magnitude (G1)magphot.mag;em.opt.IfloatJmag? Observed CPARIR Johnson J-band magnitudemagphot.mag;em.IR.JfloatnullableMassMass (1)solMassphys.massfloatTeffEffective temperature (1)Kphys.temperature.effectiveintP815/20Predicted 815/20 medium band magnitude (2)magphot.mag;em.opt.IfloatJ/ApJ/706/1484/table3Photometric candidates already detected by previous studies (table corrected by the author)ONameCounterpart name (1)phot.mag;em.opt.IcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintField[18,37] Fieldmeta.id;obs.fieldintIDRunning identification numbermeta.id;meta.mainintRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainO815/20Observed 815/20 medium band magnitude (G1)magphot.mag;em.opt.IfloatMassMasssolMassphys.massfloatTeffEffective temperatureKphys.temperature.effectiveintP815/20Predicted 815/20 medium band magnitudemagphot.mag;em.opt.IfloatIc? Cousins I-band magnitude (1)magphot.mag;em.opt.Ifloatnullable(R-I)c? (R-I)c color index (1)magphot.color;em.opt.R;em.opt.IfloatnullableTeff2? Effective temperature (1)Kphys.temperature.effectiveintnullableSimbadSimbad column added by the CDScharJ/ApJ/706/1484/spectroStellar parameters and other data for the spectroscopic follow-up samplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintField[15/20] Field numbermeta.id;obs.fieldintIDRunning identification numbermeta.id;meta.mainintRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainS/NSignal to noise ratiostat.snrfloatSpTMK spectral typesrc.spTypecharTeffEffective temperature (1)Kphys.temperature.effectiveintMassMass (1)solMassphys.massfloatO815/20Observed 815/20 medium band magnitude (G1)magphot.mag;em.opt.IfloatTphPhotometric effective temperatureKphys.temperature.effectiveintMphPhotometric masssolMassphys.massfloatP815/20Predicted 815/20 medium band magnitudemagphot.mag;em.opt.IfloatW(Ha)? H{alpha} equivalent width0.1nmspect.line.eqWidth;em.line.HalphafloatnullableW(8182)? NaI{lambda}8182{AA} equivalent width0.1nmspect.line.eqWidthfloatnullableW(8194)? NaI{lambda}8194{AA} equivalent width0.1nmspect.line.eqWidthfloatnullableRV? Radial velocitykm/sphys.veloc;pos.heliocentricfloatnullablee_RV? Radial velocity uncertaintykm/sstat.errorfloatnullablel_W(Li)Limit flag on W(Li) (1)meta.code.errorcharW(Li)? LiI equivalent width0.1nmspect.line.eqWidthfloatnullableMm[Yes/No ] Spectroscopic member? (2)pos.parallax.spectcharSimbadSimbad column added by the CDSchar