J/ApJ/868/32ivo://CDS.VizieR/J/ApJ/868/32doi:10.26093/cds/vizier.18680032CDSGoldman B.Roser S.Schilbach E.Moor A.C.Henning T.2020-07-01T08:13:49Z2018-12-14T12:25:47ZCDS support team

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

cds-question@unistra.fryoung-stellar-objectsbrown-dwarfsstellar-associationsastrometrystellar-massesstellar-ageseffective-temperatureastronomical-object-identificationphotometryvisible-astronomyScorpius-Centaurus is the nearest OB association, and its hundreds of members are divided into subgroups, including the Lower Centaurus Crux (LCC). Here we study the dynamics of the LCC area. We report the revelation of a large moving group containing more than 1800 intermediate- and low-mass young stellar objects and brown dwarfs that escaped identification until Gaia DR2 allowed a kinematic and photometric selection to be performed. We investigate the stellar and substellar content of this moving group using the Gaia DR2 astrometric and photometric measurements. The median distance of the members is 114.5pc, and 80% lie between 102 and 135pc from the Sun. Our new members cover a mass range of 0.02-5M_{sun}_ and add up to a total mass of about 700M_{sun}_. The present-day mass function follows a log-normal law with m_c_=0.22M_{sun}_ and {sigma}=0.64. We find more than 200 brown dwarfs in our sample. The star formation rate had its maximum of 8x10^-5^M_{sun}_/yr about 9Myr ago. We grouped the new members into four denser subgroups, which have increasing age from 7 to 10Myr, surrounded by "free-floating" young stars with mixed ages. Our isochronal ages, now based on accurate parallaxes, are compatible with several earlier studies of the region. The whole complex is presently expanding, and the expansion started between 8 and 10Myr ago. Two hundred members show infrared excess compatible with circumstellar disks from full to debris disks. This discovery provides a large sample of nearby young stellar and substellar objects for disk and exoplanet studies.2018ApJ...868...32Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/868/32CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/345 : Gaia DR2 (Gaia Collaboration, 2018)III/254 : 2nd Cat. of RVs with Astrometric Data (Kharchenko+, 2007)VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)J/AJ/153/257 : Comoving stars in Gaia DR1 (Oh+, 2017)J/A+A/595/A22 : 9 new open clusters within 500pc from the Sun (Roser+, 2016)J/MNRAS/461/794 : Scorpius-Centaurus K-Type Stars (Pecaut+, 2016)J/ApJS/225/15 : IR excess stars from Tycho-2 and AllWISE (Cotten+, 2016)J/MNRAS/458/3479 : SVM selection of WISE YSO Candidates (Marton+, 2016)J/MNRAS/437/391 : IR excess in Sun-like stars with WISE (Cruz-Saenz+, 2014)J/A+A/558/A53 : MW global survey of star clusters. II. (Kharchenko+, 2013)J/MNRAS/431/3222 : UKIDSS GCS Upper Sco members (Lodieu, 2013)J/ApJ/758/31 : IR photometry for members of Upper Sco (Luhman+, 2012)J/ApJ/756/133 : ScoCen debris disks around B- and A-type stars (Chen+, 2012)J/ApJ/754/30 : VISTA IR phot. of {sigma} Ori cluster (Pena Ramirez+, 2012)J/AJ/144/8 : ~100 G/K/M-type Sco-Cen complex members sp. (Song+, 2012)J/ApJ/746/154 : Kinematic parallaxes for Sco-Cen members (Pecaut+, 2012)J/ApJ/743/64 : Deep IR photometry of {sigma} Ori cluster (Bejar+, 2011)J/MNRAS/416/3108 : Membership of Sco OB2 moving group (Rizzuto+, 2011)J/ApJ/738/122 : ScoCen debris disks Around F- and G-type stars (Chen+, 2011)J/A+A/531/A92 : Deep all-sky census of the Hyades (Roeser+, 2011)J/A+A/523/A48 : Gaia photometry (Jordi+, 2010)J/A+A/492/277 : Analysis of Collinder 69 stars with VOSA (Bayo+, 2008)J/AN/328/889 : Mean Radial Velocities of open clusters (Kharchenko+, 2007)J/AJ/133/889 : Faint companions of Hipparcos stars (Lepine+, 2007)J/MNRAS/363/1111 : Tycho-2 stars with IR excess (Clarke+, 2005)J/AJ/129/1049 : Mm and sub-mm obs. of solar-type stars (Carpenter+, 2005)J/A+A/404/913 : Kinematics & HRD of Southern Young Stars (Sartori+ 2003)J/AJ/124/1670 : Post-T Tauri Stars in Sco-Cen Association (Mamajek+, 2002)J/MNRAS/313/43 : OB assoc. members in ACT+TRC Catalogs (Hoogerwerf, 2000)J/AJ/117/354 : OB associations from Hipparcos (de Zeeuw+, 1999)J/A+A/337/403 : Low-mass stars evolutionary models (Baraffe+ 1998)J/ApJ/497/330 : Candidate main-sequence stars (Mannings+, 1998)J/A+AS/106/275 : Theoretical isochrones (Bertelli+ 1994)J/A+A/216/44 : Walraven photometry in Sco-Cen association (De Geus+, 1989)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/868/32https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/868/32http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/868/32https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/868/32https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/868/32http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/868/32GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/868/32/members (Lower Centaurus Crux (LCC) member parameters (see Table 4))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/868/32/members?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/868/32/members?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/868/32/members?GETtext/xml+votable180.050000true199.92575030691-48.837108350360.0055555555555555564/2602 2689 2691 2697 2698 2701 2720 5/9492 9493 9537 10378 10400 10401 10402 10412 10415 10416 10425 10426 10427 10464 10466 10753 10755 10760 10761 10763 10768 10772 10773 10775 10777 10778 10779 10780 10781 10782 10784 10785 10786 10796 10798 10799 10801 10802 10803 10809 10811 10813 10816 10817 10819 10824 10826 10848 10850 10884 10886 10887 10888 10896 6/37127 37134 37136 37137 37145 37173 37185 37186 37190 37196 37197 37200 37202 37203 37204 37206 37207 37212 37237 37888 37889 37890 37892 37893 37894 37901 37905 37907 37909 37917 37918 37919 37951 37953 37954 37955 37956 37957 37959 37962 37963 37964 37965 37978 37980 37988 37995 38001 38100 38144 38145 38146 38154 38160 38161 38163 38166 38172 38175 38176 38177 38191 38208 38215 41117 41134 41139 41148 41197 41387 41478 41480 41482 41484 41489 41492 41493 41500 41505 41507 41508 41509 41510 41516 41518 41519 41522 41524 41526 41528 41530 41531 41532 41542 41546 41547 41558 41574 41577 41583 41594 41612 41613 41615 41616 41617 41618 41622 41624 41625 41627 41628 41629 41630 41652 41656 41657 41658 41668 41670 41673 41675 41677 41681 41684 41686 41690 41692 41696 41698 41715 41717 41718 41719 41722 41723 41726 41727 41760 41860 41862 41869 41871 41880 41886 41888 41890 41891 41894 41895 41896 41898 41899 41902 41903 41905 41906 41907 41912 43009 43010 43011 43016 43017 43019 43048 43049 43051 43076 43077 43080 43082 43083 43085 43086 43087 43096 43097 43098 43104 43105 43107 43133 43134 43135 43148 43149 43150 43188 43189 43190 43201 43202 43203 43232 43233 43240 43241 43243 43249 43250 43251 43256 43257 43258 43260 43261 43262 43272 43273 43274 43280 43283 43288 43290 43300 43301 43302 43308 43310 43311 43396 43398 43424 43426 43540 43541 43543 43557 43558 43561 43563 43564 43570 43571 43572 43574 43575 43580 43588 43589 43591 43592 43593 43595 43596 43598 43601 43602 43603 43608 43609 43610 43616 43624 43626 43628 43657 43658 43659 43663 43664 43668 43673 43682 43690 43691 43692 43693https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/868/32?format=asciiOpticaldefaultJ/ApJ/868/32/membersLower Centaurus Crux (LCC) member parameters (see Table 4)FG[638/5.5e+08] G-band mean flux (phot_g_mean_flux)phot.flux.density;em.optdoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintDR2NameGaia DR2 designation (designation)meta.id;meta.maincharGroupGroup (A, A0, B, C or Z) (1)meta.idcharRA_ICRS[164.4/228.1] Gaia DR2 barycentric right ascension (ICRS) at Ep=2015.5 (ra)degpos.eq.ra;meta.mainDE_ICRS[-77/-40.8] Gaia DR2 barycentric declination (ICRS) at Ep=2015.5 (dec)degpos.eq.dec;meta.maine_RA_ICRS[0.01/0.4] Standard error of RAdeg (e_RA*cosDE) (ra_error)masstat.error;pos.eq.rafloate_DE_ICRS[0.01/0.5] Standard error of DEdeg (dec_error)masstat.error;pos.eq.decfloatpmRA[-43/-21] Proper motion in RA direction (pmRA*cosDE) (pmra)mas/yrpos.pm;pos.eq.radoublepmDE[-31.2/5] Proper motion in declination direction (pmdec)mas/yrpos.pm;pos.eq.decdoublee_pmRA[0.02/0.7] Standard error of pmRA direction (pmra_error)mas/yrstat.error;pos.pm;pos.eq.rafloate_pmDE[0.02/0.8] Standard error of pmDE direction (pmdec_error)mas/yrstat.error;pos.pm;pos.eq.decfloatPlx[7/12] Absolute stellar parallax (parallax)maspos.parallaxdoublee_Plx[0.02/0.6] Standard error of parallax (parallax_error)masstat.error;pos.parallaxfloatRPlx[14.5/418.5] Parallax divided by its error (parallax_over_error)stat.fit.omcdoubleRADEcor[-0.7/1] Correlation between RA and DEC (ra_dec_corr)stat.correlationRAPlxcor[-1/0.5] Correlation between RA and parallax (ra_parallax_corr)stat.correlationRApmRAcor[-0.9/0.5] Correlation between RA and pmRA (ra_pmra_corr)stat.correlationRApmDEcor[-0.7/0.7] Correlation between RA and pmDE (ra_pmdec_corr)stat.correlationDEPlxcor[-1/0.6] Correlation between DEC and parallax (dec_parallax_corr)stat.correlationDEpmRAcor[-0.8/0.8] Correlation between DEC and pmRA (dec_pmra_corr)stat.correlationDEpmDEcor[-1/0.9] Correlation between DEC and pmDE (dec_pmdec_corr)stat.correlationPlxpmRAcor[-0.7/0.8] Correlation between parallax and pmRA (parallax_pmra_corr)stat.correlationfloatPlxpmDEcor[-0.9/0.8] Correlation between parallax and pmDE (parallax_pmdec_corr)stat.correlationfloatpmRApmDEcor[-0.8/0.9] Correlation between pmRA and pmDE (pmra_pmdec_corr)stat.correlationfloatNAL[69/945] Total number of AL observations (= CCD transits) (astrometric_n_obs_al)meta.numberintNAC[0/919] Total number of observations AC (astrometric_n_obs_ac)meta.numberintNgAL[69/940] Number of good observations AL (astrometric_n_good_obs_al)meta.numberintNbAL[0/74] Number of bad observations AL (astrometric_n_bad_obs_al)meta.numberintgofAL[-1/221] Goodness of fit statistic of model wrt along-scan observations (astrometric_gof_al)stat.fit.goodnessdoublechi2AL[85/93841] AL chi^2^ value (astrometric_chi2_al)stat.fit.chi2doubleepsi[0/2] Excess noise of the source (astrometric_excess_noise)masstat.fit.paramfloatsepsi[0/1759] Significance of excess noise (astrometric_excess_noise_sig)stat.fit.paramdoubleSolved[31] Which parameters have been solved for? (31=all five astrometric parameters were estimated) (astrometric_params_solved)meta.numberintAPF[0] Primary or secondary (false=secondary source) (astrometric_primary_flag)meta.codeintWAL[0.2/516] Mean astrometric weight of the source (astrometric_weight_al)mas**-2stat.weightdoublepscol[0.9/2.2] Astrometrically determined pseudocolour of the source (astrometric_pseudo_colour)um**-1stat.fit.paramfloate_pscol[0.003/0.08] Standard error of the pseudocolour of the source (astrometric_pseudo_colour_error)um**-1stat.errorfloatfvarpi[-0.4/0.4] Mean Parallax factor AL (mean_varpi_factor_al)arith.factor;pos.parallaxfloatMatchObsA[8/108] Matched FOV transits used in the AGIS solution (astrometric_matched_observations)meta.numberintNper[7/20] Number of visibility periods used in Astrometric solution (visibility_periods_used)meta.numberintamax[0.03/0.9] The longest semi-major axis of the 5-d error ellipsoid (astrometric_sigma5d_max)phys.angSize.smajAxisdoubleVperp[-2.4/2.1] Observed tangential velocity perpendicular to the convergent point direction (vperp)km/sphys.veloc.transversedoubletype[0] The type of the source mainly used for frame rotation (0=ordinary source) (frame_rotator_object_type)meta.codeintMatchObs[10/110] The total number of FOV transits matched to this source (matched_observations)meta.numberintDup[0] Source with duplicate sources (false) (duplicated_source)meta.codeinto_Gmag[81/946] Number of observations contributing to G photometry (phot_g_n_obs)meta.numberinte_FG[0.9/2.1e+06] FG error (phot_g_mean_flux_error)stat.errordoubleRFG[31/5654] G-band mean flux divided by its error (phot_g_mean_flux_over_error)stat.fit.omcdoubleGmag[3.8/18.7] G-band mean magnitude (Vega) (phot_g_mean_mag)phot.mag;em.optdoubleo_BPmag[2/103] Number of observations contributing to BP photometry (phot_bp_n_obs)meta.numberintFBP[38/4.3e+08] Mean flux in the integrated BP band (phot_bp_mean_flux)phot.flux.density;em.opt.Bdoublee_FBP[3.9/1.2e+06] Error on FBP (phot_bp_mean_flux_error)stat.errordoubleRFBP[4/2465] Integrated BP mean flux divided by its error (phot_bp_mean_flux_over_error)stat.fit.omcdoubleBPmag[3.7/21.4] Integrated BP mean magnitude (Vega) (phot_bp_mean_mag)phot.mag;em.opt.Bdoubleo_RPmag[2/103] Number of observations contributing to RP photometry (phot_rp_n_obs)meta.numberintFRP[1103/2e+08] Mean flux in the integrated RP band (phot_rp_mean_flux)phot.flux.density;em.opt.Rdoublee_FRP[5/577480] Error on FRP (phot_rp_mean_flux_error)stat.errordoubleRFRP[5/2173] Integrated RP mean flux divided by its error (phot_rp_mean_flux_over_error)stat.fit.omcdoubleRPmag[4/17.2] Integrated RP mean magnitude (Vega) (phot_rp_mean_mag)phot.mag;em.opt.RdoubleE(BR/RP)[1.1/1.8] BP/RP excess factor (phot_bp_rp_excess_factor)phot.color.excessfloatMode[0/1] Photometry processing mode (phot_proc_mode)meta.codeintRV[-29/34.1]? Spectroscopic radial velocity in the solar barycentric reference frame (radial_velocity)km/sphys.veloc;pos.barycenterfloatnullablee_RV[0.2/19.4]? Radial velocity error (radial_velocity_error)km/sstat.errorfloatnullableo_RV[0/37] Number of transits used to compute radial velocity (rv_nb_transits)meta.numberintVarPhotometric variability flag ("VARIABLE" = 36 occurrences) (phot_variable_flag)meta.code;src.varcharGLON[285.2/319] Galactic longitude (l)degpos.galactic.lonGLAT[-15.3/21.7] Galactic latitude (b)degpos.galactic.latdoubleELONEcliptic longitude (ecl_lon)degpos.ecliptic.lonELATEcliptic latitude (ecl_lat)degpos.ecliptic.latdoublefPriam[100001/102002]? Flags for the Apsis-Priam results (priam_flags)meta.codeintnullableTeffA[3286/9705]? Stellar effective temperature (estimate from Apsis-Priam) (teff_val)Kphys.temperature.effectivefloatnullableb_TeffA[3115/9534]? Uncertainty (lower) on TeffA (16th percentile) (teff_percentile_lower)Kstat.errorfloatnullableB_TeffA[3343/9947]? Uncertainty (upper) on TeffA (84th percentile) (teff_percentile_upper)Kstat.errorfloatnullableAG[0.02/3]? Estimate of extinction in the G band from Apsis-Priam (a_g_val)magphys.absorptionfloatnullableb_AG[0/2.6]? Uncertainty (lower) on AG estimate from Apsis-Priam (16th percentile) (a_g_percentile_lower)magphot.magfloatnullableB_AG[0.06/3.2]? Uncertainty (upper) on AG estimate from Apsis-Priam (84th percentile) (a_g_percentile_upper)magphot.magfloatnullableE(BP-RP)[0.01/1.5]? Estimate of redenning E(BP-RP) from Apsis-Priam (e_bp_min_rp_val)magphot.color.excessfloatnullableb_E(BP-RP)[0/1.3]? Uncertainty (lower) on E(BP-RP) estimate from Apsis-Priam (16th percentile) (e_bp_min_rp_percentile_lower)magstat.errorfloatnullableB_E(BP-RP)[0.03/1.7]? Uncertainty (upper) on E(BP-RP) estimate from Apsis-Priam (84th percentile) (e_bp_min_rp_percentile_upper)magstat.errorfloatnullablefFLAME[200111]? Flags for the Apsis-FLAME results (flame_flags)meta.codeintnullableRad[0.5/3]? Estimate of radius from Apsis-FLAME (radius_val)solRadphys.size.radiusfloatnullableb_Rad[0.3/3]? Uncertainty (lower) on radius estimate from Apsis-FLAME (16th percentile) (radius_percentile_lower)solRadstat.error;phys.size.radiusfloatnullableB_Rad[0.5/3.1]? Uncertainty (upper) on radius estimate from Apsis-FLAME (84th percentile) (radius_percentile_upper)solRadstat.error;phys.size.radiusfloatnullableLum[0.03/26]? Esimate of luminosity from Apsis-FLAME (lum_val)solLumphys.luminosityfloatnullableb_Lum[0.03/25.8]? Uncertainty (lower) on luminosity estimate from Apsis-FLAME (16th percentile) (lum_percentile_lower)solLumstat.error;phys.luminosityfloatnullableB_Lum[0.03/26.3]? Uncertainty (upper) on luminosity estimate from Apsis-FLAME (84th percentile) (lum_percentile_upper)solLumstat.error;phys.luminosityfloatnullableRVpred[5.5/16.7] Predicted radial velocity (vr_pred)km/sphys.veloc;pos.heliocentricfloatVpar[18.3/21.5] Observed tangential velocity toward the convergent point (vpar)km/sphys.veloc.transversefloate_Vpar[0.05/1.3] Uncertainty on the observed tangential velocity toward the convergent point (e_vpar)km/sstat.errorfloate_Vperp[0.01/0.5] Uncertainty on the observed tangential velocity perpendicular to the convergent point direction (e_vper)km/sstat.errorfloatVppcor[-0.9/0.8] Correlation between the observed tangential velocities toward and perpendicular to the convergent point direction (vparvperpcor)stat.correlationdoubleXgal[26/103] X galactic coordinate derived from Gaia DR2 parameters (x_gal)pcpos.cartesian.x;pos.galacticdoubleYgal[-134.1/-64.6] Y galactic coordinate derived from Gaia DR2 parameters (y_gal)pcpos.cartesian.y;pos.galacticdoubleZgal[-30.7/51] Z galactic coordinate derived from Gaia DR2 parameters (z_gal)pcpos.cartesian.z;pos.galacticdoubleAgeC[0.001/0.1]? Age according to the CIFIST isochrones (age_CIFIST)Gyrtime.agefloatnullableMassC[0.02/1.4]? Mass according to the CIFIST isochrones (Mass_CIFIST)solMassphys.massfloatnullableTeffC[2632/6766]? Effective temperature according to the CIFIST isochrones (Teff_CIFIST)Kphys.temperature.effectivefloatnullablelogLumC[-3/0.6]? log_10 of bolometric luminosity according to the CIFIST isochrones (Lum_CIFIST)log(solLum)phys.luminosityfloatnullableloggC[3.4/5]? log_10 of gravity according to the CIFIST isochrones (logg_CIFIST)log(g.cm**-1.s**-2)phys.gravityfloatnullableAgeP[5e+06/1e+08] Age according to the Parsec isochrones (Age_P)yrtime.agedoubleMassP[0.1/5.4] Initial mass according to the Parsec isochrones (mass_P)solMassphys.massfloatlogLumP[-2.7/3.1] log_10 of bolometric luminosity according to the Parsec isochrones (logL_P)log(solLum)phys.luminosityfloatlogTeffP[3.4/4.3] log_10 of effective temperature according to the Parsec isochrones (logTe_P)log(K)phys.temperature.effectivefloatloggP[3.7/4.8] log_10 of gravity according to the Parsec isochrones (logg_P)log(g.cm**-1.s**-2)phys.gravityfloatRecovR[0.6/1] Fraction of recovered stars of same G magnitude (recovery_rate)stat.fit.paramfloatAge[0.001/0.11] Best age (Age)Gyrtime.age;meta.modelleddoubleMass[0.02/5.4] Best mass (Mass)solMassphys.massfloatTeff[2632/16726] Best effective temperature (Teff)Kphys.temperature.effective;meta.modelleddoubleLogLum[-3/3.1] log_10 of best bolometric luminosity (LogL)log(solLum)phys.luminosityfloatWISEAID of AllWISE detection (JHHMMSS.ss+DDMMSS.s) (AllWISE_ID)meta.id.crosscharlogLSED[-3.8/590]? log_10 of bolometric luminosity according to the VOSA fit, used for the circumstellar disk analysis (LogL_SED)log(g.cm**-1.s**-2)phys.luminosityfloatnullableTeffSED[1200/18000]? Effective temperature according to the VOSA fit, used for the circumstellar disk analysis (Teff_SED)Kphys.temperature.effective;meta.modelledintnullableDkTypeCircumstellar disk classification (disk_type)src.classcharSNamePrimary SIMBAD name (Simbad_name)meta.id.crosscharRef? Reference for circumstellar disk (Ref) (2)meta.ref;pos.frameintnullableSimbadSimbad column added by the CDSmeta.ref.urlchar_RA.icrsRight ascension (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) at Epoch=J2000, proper motions taken into accountdegpos.eq.decnullableindexed