J/ApJ/941/143ivo://CDS.VizieR/J/ApJ/941/143CDSKerr R.Kraus A.L.Murphy S.J.Krolikowski D.M.Bedding T.R.,Rizzuto A.C.2025-11-12T14:34:55Z2025-11-12T15:18:08ZCDS support team

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

cds-question@unistra.frstellar-associationsradial-velocityline-intensitiesstellar-massesyoung-stellar-objectsvisible-astronomytrigonometric-parallaxtwo-color-diagramsThe study of young associations is essential for building a complete record of local star formation processes. The Fornax-Horologium association (FH), including the {chi}1 Fornacis cluster, represents one of the nearest young stellar populations to the Sun. This association has recently been linked to the Tuc-Hor, Carina, and Columba associations, building an extensive "Austral Complex" almost entirely within 150pc. Using Gaia astrometry and photometry in addition to new spectroscopic observations, we perform the deepest survey of FH to date, identifying over 300 candidate members, nearly doubling the known population. By combining this sample with literature surveys of the other constituent populations, we produce a contiguous stellar population covering the entire Austral Complex, allowing the definitions of subpopulations to be reassessed along with connections to external populations. This analysis recovers new definitions for FH, Tuc-Hor, Columba, and Carina, while also revealing a connection between the Austral complex and the Sco-Cen-affiliated Platais 8 cluster. This suggests that the Austral complex may be just a small component of a much larger and more diverse star formation event. Computing ages and tracing stellar populations back to formation reveals two distinct nodes of cospatial and continuous formation in the Austral Complex, one containing Tuc-Hor, and the other containing FH, Carina, and Columba. This mirrors recent work showing similar structure elsewhere, suggesting that these nodes, which only emerge through the use of traceback, may represent the clearest discrete unit of local star formation, and a key building block needed to reconstruct larger star-forming events.2022ApJ...941..143Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/941/143CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/ocl : Optically visible open clusters and Candidates (Dias+ 2002-2015)III/254 : 2nd Cat. of RVel with Astrometric Data (Kharchenko+, 2007)V/137 : Extended Hipparcos Compilation (XHIP) (Anderson+, 2012)I/337 : Gaia DR1 (Gaia Collaboration, 2016)III/279 : RAVE 5th data release (Kunder+, 2017)I/345 : Gaia DR2 (Gaia Collaboration, 2018)J/A+AS/135/503 : HIP southern B8-F2 stars radial velocities (Grenier+ 1999)J/AJ/123/3356 : Palomar/MSU nearby star sp. survey. III. (Gizis+, 2002)J/A+A/438/1163 : Catalogue of Open Cluster Data (COCD) (Kharchenko+, 2005)J/AJ/132/866 : New M dwarfs in solar neighborhood (Riaz+, 2006)J/A+A/460/695 : Associations Containing Young stars (Torres+, 2006)J/AN/328/889 : Mean Radial Velocities of open clusters (Kharchenko+, 2007)J/AJ/133/2524 : Spectra of young nearby stars (White+, 2007)J/A+A/508/833 : SACY III. Li abundances (da Silva+, 2009)J/ApJS/190/1 : A survey of stellar families (Raghavan+, 2010)J/A+A/530/A138 : Geneva-Copenhagen survey re-analysis (Casagrande+, 2011)J/ApJ/731/8 : Multiple star formation in Taurus-Auriga (Kraus+, 2011)J/A+A/546/A61 : Radial velocities for XHIP catalogue (de Bruijne+, 2012)J/A+A/551/A46 : Compiled phot. for Cham I & II members (Lopez Marti+, 2013)J/ApJ/762/88 : Young stellar kinematic group cand. members (Malo+, 2013)J/A+A/568/A26 : SACY. V. Multiple systems (Elliott+, 2014)J/AJ/147/146 : Spectroscopy of Tuc-Hor candidate members (Kraus+, 2014)J/ApJ/788/81 : BANYAN III. RVel & rotation of low-mass stars (Malo+, 2014)J/MNRAS/454/593 : Young moving groups in solar neighbourhood (Bell+, 2015)J/ApJS/220/18 : BDKP IV. RVs of M & L dwarfs with MagE (Burgasser+, 2015)J/A+A/573/A126 : VLT/NaCo Large program I. Sample (Desidera+, 2015)J/ApJS/225/10 : Kinematic analysis of M7-L8 dwarfs (Faherty+, 2016)J/AJ/154/69 : ACRONYM II. {beta} Pictoris Moving Group (Shkolnik+, 2017)J/A+A/618/A93 : Gaia DR2 open clusters in the MW (Cantat-Gaudin+, 2018)J/MNRAS/475/1960 : ESPaDOnS spectropolarimeter obs. of M dwarfs (Fouque+, 2018)J/ApJ/862/138 : BANYAN. XIII. Young assoc. with Gaia DR2 (Gagne+, 2018)J/ApJ/860/43 : BANYAN. XII. New members from Gaia-Tycho data (Gagne+, 2018)J/ApJ/856/23 : BANYAN. XI. The BANYAN {Sigma} algorithm (Gagne+, 2018)J/A+A/614/A76 : CARMENES input catalogue of M dwarfs. III. (Jeffers+, 2018)J/AJ/156/84 : APOGEE-2 survey of Orion Complex. II. (Kounkel+, 2018)J/A+A/616/A7 : Gaia DR2 radial velocity standard stars (Soubiran+, 2018)J/A+A/615/A12 : Nearby open clusters TGAS and HSOY reanalysis (Yen+, 2018)J/A+A/620/A172 : Solar neighbourhood young stars 3D mapping (Zari+, 2018)J/ApJ/877/60 : YMGs. I. Young binaries & lithium-rich stars (Bowler+, 2019)J/A+A/621/A115 : Vela OB2 members (Cantat-Gaudin+, 2019)J/AJ/158/122 : Local structure & SFH of the MW (Kounkel+, 2019)J/ApJ/870/32 : Kinematics in young star clusters & assoc. (Kuhn+, 2019)J/MNRAS/489/2189 : Nearby young moving groups with ML (Lee+, 2019)J/AJ/157/234 : ACRONYM. III. Cand. young low-mass stars (Schneider+, 2019)J/A+A/626/A31 : Radial velocities of nearby stars (Sperauskas+, 2019)J/ApJS/245/34 : Abund. for 6 million stars from LAMOST DR5 (Xiang+, 2019)J/A+A/654/A122 : X1 Fornacis cluster DANCe (Galli+, 2021)J/ApJ/917/23 : SPYGLASS. I. Mapping young stellar structures (Kerr+, 2021)J/MNRAS/513/5727 : Li study with GESiDR6's PMS stars cluster (Binks+, 2022)J/A+A/664/A175 : MW low mass young stars from Gaia EDR3 (Prisinzano+, 2022)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/941/143https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/941/143http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/941/143https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/941/143https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/941/143http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/941/143GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/941/143/table2 (Stars identified as credible candidate members of Fornax-Horologium and adjoining Austral populations)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/941/143/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/941/143/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/941/143/table2?GETtext/xml+votable180.050000true62.5444-32.970.005555555555555556Cone search capability for table J/ApJ/941/143/table1 (Spectroscopic properties of members in Fornax- Horologium and the connected Tuc-Hor, Columba, and Carina associations)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/941/143/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/941/143/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/941/143/table1?GETtext/xml+votable180.050000true62.5444-32.970.005555555555555556Cone search capability for table J/ApJ/941/143/table5 (Binaries in the Austral complex (see Section 3.3))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/941/143/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/941/143/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/941/143/table5?GETtext/xml+votable180.050000true55.0453-27.36860.0055555555555555565/8634 8965 6/46 840 1412 1429 3109 3122 3163 3566 3922 9507 13688 14290 14308 15674 16220 16424 16486 16547 16719 16993 17274 17394 17502 17606 19577 20125 20490-20491 20513 20539 20612 20617 20624 20634 20636 20650 20653 20657-20658 20690 20715 20727 20871 20906 20996 21007 21023 21031 21050 21061 21080 21082-21083 21090 21094 21116 21118 21135 21139 21142 21145 21164 21199 21218 21239 21245 21364-21365 21377 21388 21418 21422 21424 21428 21520 22066-22067 22146 22535 22567 22581 22619 23068 23176 23272 23870 24506 32792-32793 32805 32836 32844 32868 32875 32881 32890-32891 32912 32917 32930 32937 32950 32970 33006 33042 33052-33053 33065 33116 33129 33145 33170 33186 33269 33276 33312 33334 33342 33349 33355 33361 33367 33382 33411 33422 33429 33456 33461 33464 33482 33500-33501 33512-33513 33517 33520 33523 33529 33545 33551 33565 33583 33593-33594 33643 33654 33666 33670 33689 33694 33697 33704 33706-33707 33718 33737 33744 33756 33758 33762 33766 33780-33781 33787 33791 33817 33848 33856 33894 33919 33956 33965 33981 33993 33996 34008 34012 34017 34043 34050-34051 34058 34102 34127 34146 34164-34165 34175 34179 34194 34196 34198 34201 34203 34208 34233 34235 34244 34250 34269-34271 34293 34297 34301 34308 34312 34327 34330 34332 34338 34346 34348 34364 34376 34378 34380 34384 34393 34401-34403 34406 34409-34411 34415 34417-34418 34423 34432 34434-34436 34444 34450-34451 34453 34455 34460 34462 34464 34467-34468 34472 34476 34481-34482 34485-34487 34491 34493-34495 34497 34499-34500 34503-34504 34509 34513 34520 34525-34526 34529-34531 34533-34534 34540-34542 34546-34548 34552-34554 34559 34563 34566 34573 34575 34577 34585-34586 34588 34596 34599 34606-34607 34611 34616-34617 34623 34634 34640 34668-34669 34681 34683 34690-34692 34694 34699 34701 34707 34713 34720 34723-34724 34730 34732-34733 34735-34737 34739 34745 34748 34753 34757 34760 34781 34789-34790 34793-34795 34819 34823 34825 34829-34830 34834 34840 34843 34857 34880 34885-34886 34896 34909 34930 34959 34963 34998 35002 35027 35037 35077 35123 35131 35143 35147 35149 35157 35161 35165 35172 35179 35197 35205 35268 35271 35289 35298 35317-35318 35415 35497 35509 35531 35627 35640 35655 35664 35679 35706 35844-35845 35854 35857 35859 35865-35866 35873 35875 35880 35882 35885 35891 35896 35904-35905 35907 35910-35911 35913 35919 35924 35928-35930 35934 35939 35942 35944-35945 35952 35954 35958 35962-35963 35965 35970 35984 35994 36001 36005 36030-36031 36036 36039 36042 36059 36064 36082 36096 36102 36104-36105 36107 36109 36115 36119 36121-36122 36125 36130-36133 36135-36137 36146 36148 36152 36159 36169 36171 36174 36196 36228 36233 36239 36245-36246 36248 36250 36252 36257 36308 36346 36356 36416 36487 36578 36626 36676 36686 36770 36803 36869 36901 36907 36980 37002 37006 37027 37047 37063 37065 37072 37074-37075 37079 37085 37090 37097 37101 37104 37114 37155 37163 37166 37175 37227 37233 37262 37302 37304 37310-37311 37319 37324-37325 37335 37359 37362-37363 37385 37387 37414 37421-37422 37455 37480 37491 37494 37498 37526 37561 37564 37566-37567 37573 37591 37611 37638 37643 37647 37652 37664-37665 37679 37684 37695 37714 37716 37730 37734 37745 37757 37781 37783 37788 37801 37805 37827 37838 37970 38050 38061 38408 38440 38920 38947 38985 39019 39044 39056-39057 39175 39179 39450 39489 39513 39518 39544 39568-39569 39579 39584 39586 39634 39681 39848 39854 40961 40965 41131 41184 41247 42021 45072-45073 45104 45120 45168 45195 45306 45324 45336 45345 45378 45382 45389 45391 45394 45416 45453 45471-45472 45492 45503 45510 45538 45544 45657 45694 45770 45797 45852 45876 45894 45927 45931 45944 45967 45977 46082 46084 46087 46201 46207 46339 46536 46601 46629 46692 46739 46758 47376 481631.9867573869263685e-19 3.916500758235022e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/941/143?format=asciiOpticaldefaultJ/ApJ/941/143/table2Stars identified as credible candidate members of Fornax-Horologium and adjoining Austral populationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSpspectroscopic properties (Table 1)meta.ref.urlcharGaiaGaia DR3 source identifiermeta.id;meta.mainprimaryGroupLiterature group the star was initially assigned to (1)meta.id.parentcharSrcSource the star was drawn from (2)meta.bibcharReg[1/6] ID of the HDBSCAN subgroup (3)meta.codeintRA_ICRSRight Ascension (ICRS) at Epoch=2016.0degpos.eq.ra;meta.mainDE_ICRSDeclination (ICRS) at Epoch=2016.0degpos.eq.dec;meta.mainplx[3.5/20] Gaia DR3 parallaxmaspos.parallax.trigfloatSimbadSimbad column added by the CDSmeta.ref.urlcharGmag[-0.2/5]? Gaia DR3 G-band magnitudemagphot.mag;em.optfloatnullableGBP-GRP[5.9/63] Gaia DR3 GBP-GRP colormagphot.color;em.opt.B;em.opt.RfloatMstar[0.09/3.7] MasssolMassphys.massfloatD[0/1] Clustering proximitymeta.codefloatA[0/1] Boolean solution to the Astrometric quality cut from SPYGLASS-I (4)meta.codeintP[0/1] Boolean solution to the Photometric quality cut from SPYGLASS-I (4)meta.codeintPY[0/1] Flag for the photometric youth determination of the star (4)meta.codeintV[-1/1] Flag to represent the results of our velocity membership cuts (4)meta.codeintF[0/10]? Flag for other notable features (4)meta.codeintnullableJ/ApJ/941/143/table1Spectroscopic properties of members in Fornax- Horologium and the connected Tuc-Hor, Columba, and Carina associationsGaiaGaia DR3 source identifiermeta.id;meta.mainrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRA_ICRSRight Ascension (ICRS) at Epoch=2016.0degpos.eq.ra;meta.mainDE_ICRSDeclination (ICRS) at Epoch=2016.0degpos.eq.dec;meta.mainRVel[-26/94]? Radial Velocitykm/sspect.dopplerVelocfloatnullablee_RVel[0/37.4]? Uncertainty in RVelkm/sstat.error;spect.dopplerVelocfloatnullabler_RVelSource for RVel (see refs.dat file)meta.ref;spect.dopplerVeloccharEWLi[-0.09/2.3]? Equivalent width, Lithium0.1nmspect.line.eqWidthfloatnullablee_EWLi[0/1.9]? Uncertainty in EWLi0.1nmstat.error;spect.line.eqWidthfloatnullabler_EWLiSource for EWLi (see refs.dat file)meta.ref;spect.line.eqWidthcharEWHb[-36.8/3.8]? Equivalent width, H{beta}0.1nmspect.line.eqWidth;em.line.Hbetafloatnullablee_EWHb[0/1]? Uncertainty in EWHb0.1nmstat.error;spect.line.eqWidth;em.line.Hbetafloatnullabler_EWHbSource for EWHb (see refs.dat file)meta.ref;spect.line.eqWidth;em.line.HbetacharJ/ApJ/941/143/table5Binaries in the Austral complex (see Section 3.3)Gmag[4.6/19.7] Gaia DR3 G-band magnitudemagphot.mag;em.optfloatplx[6.6/34.3] Gaia DR3 parallaxmaspos.parallax.trigfloatSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGaiaGaia DR3 source identifiermeta.id;meta.mainSyst[0/100] Sequential system identifiermeta.id;pos.frameintm_SystNumber of stars in this systemmeta.numberintnullableSep[0/8533] Projected separation (1)aupos.angDistanceintRA_ICRSRight Ascension (ICRS) at Epoch=2016.0degpos.eq.ra;meta.mainDE_ICRSDeclination (ICRS) at Epoch=2016.0degpos.eq.dec;meta.mainJ/ApJ/941/143/refsReferencesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRefReference codemeta.notecharAuthFirst author's name(s)meta.bib.authorcharBibCodeBibcode of the referencemeta.bib.bibcodecharCommCommentmeta.notechar