J/A+A/677/A59ivo://CDS.VizieR/J/A+A/677/A59doi:10.26093/cds/vizier.36770059CDSRatzenboeck S.Grossschedl J.Moeller T.Alves J.Bomze I.Meingast M.2026-01-30T20:01:00Z2023-09-06T07:15:04ZCDS support team

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

cds-question@unistra.fropen-star-clustersastrometrystellar-distancevisible-astronomyWe present a new clustering method, significance mode analysis (SigMA), for extracting co-spatial and co-moving stellar populations from large-scale surveys such as ESA Gaia. The method studies the topological properties of the density field in the multidimensional phase space. We validated SigMA on simulated clusters and find that it outperforms competing methods, especially in cases where many clusters are closely spaced. We applied the new method to Gaia DR3 data of the closest OB association to Earth, Scorpio-Centaurus (Sco-Cen), and find more than 13000 co-moving young objects, about 19% of which have a substellar mass. SigMA finds 37 co-moving clusters in Sco-Cen. These clusters are independently validated by their narrow Hertzsprung-Russell diagram sequences and, to a certain extent, by their association with massive stars too bright for Gaia, and are hence unknown to SigMA. We compared our results with similar recent work and find that the SigMA algorithm recovers richer populations, is able to distinguish clusters with velocity differences down to about 0.5km/s, and reaches cluster volume densities as low as 0.01sources/pc^3^. The 3D distribution of these 37 coeval clusters implies a larger extent and volume for the Sco-Cen OB association than typically assumed in the literature. Additionally, we find the association more actively star-forming and dynamically complex than previously thought. We confirm that the star-forming molecular clouds in the Sco-Cen region, namely, Ophiuchus, L134/L183, Pipe Nebula, Corona Australis, Lupus, and Chamaeleon, are part of the Sco-Cen association. The application of SigMA to Sco-Cen demonstrates that advanced machine learning tools applied to the superb Gaia data allows an accurate census of the young populations to be constructed, which in turn allows us to quantify their dynamics and recreate the recent star formation history of the local Milky Way.2023A&A...677A..59Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/677/A59CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/677/A59https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/677/A59http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/677/A59https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/677/A59https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/677/A59http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/677/A59GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/677/A59/table3 (Overview of the 37 SigMA clusters in Sco-Cen, assigned to seven subregions)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/677/A59/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/677/A59/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/677/A59/table3?GETtext/xml+votable180.050000true246.5512-24.18950.005555555555555556Cone search capability for table J/A+A/677/A59/tablee1 (Sco-Cen cluster information)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/677/A59/tablee1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/677/A59/tablee1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/677/A59/tablee1?GETtext/xml+votable180.050000true181.8890789-39.54844310.0055555555555555563/665 667 670 672 677 4/2602 2604 2622-2623 2650-2651 2665-2667 2672 2674-2675 2684 2686-2687 2694-2698 2700-2701 2703-2706 2712-2713 2716 2720 2752-2754 2756-2757 2768-2769 2772 5/7202 7298-7300 7302-7303 7307-7308 7310 7333 7346 7680 7683 7729 9239 9280 9282 9300-9301 9477 9489 9492 9537 9540 10280 10283 10368 10376 10378-10379 10381 10395-10396 10398 10400-10402 10412 10414-10415 10420 10422-10423 10425-10427 10429-10430 10464-10466 10470 10474 10479 10484 10486 10554-10555 10559 10583 10590 10599 10610-10611 10613 10616 10618-10621 10624 10630-10631 10633 10637-10639 10657-10659 10692 10694-10695 10704 10706 10708 10712 10714-10715 10740-10742 10768-10769 10771-10773 10775 10796 10798-10799 10809-10811 10828 10830-10831 10856-10858 10860 10863 10869 10884-10886 10888-10889 10896 10899-10900 10944 10960 11020-11021 11023 11033 11036 11038 11044 11059-11060 11080-11081 11083-11085 11092-11094 11096-11097 11099-11100 11108 11953 11955-11956 11958 11960-11961 11963-11964 6/24580-24582 24589 24604 24608 24627 24629 24644 28674-28676 28678-28680 28682-28684 28688 28690-28692 28695 28697 28701-28702 28709-28710 28712 28716-28718 28723 28730 28736-28737 28739-28741 28743-28744 28748-28749 28801 28806-28807 28815 28818-28819 28832-28833 28835-28836 28840 28842-28844 28846-28847 28849 28856 28859 28866 29184-29185 29187 29189-29191 29206 29216-29217 29219-29222 29224 29226-29227 29236-29238 29245-29247 29249 29280 29287-29290 29295 29312 29315 29319-29320 29323 29325 29327 29329-29331 29337-29339 29341-29344 29347-29348 29351-29352 29354 29356 29358-29359 29361 29363 29368 29370 29377-29380 29389-29392 29394 29412-29413 29415 29424 29427 30728 30731 30738 30740-30741 30743-30745 30750 30752 30756 30758-30761 30769 30772 30828 30838-30839 30843 30847 30851 30856 30858 30890 30912 30914-30915 30924 30929 30934 31016 31240 31242 31247 31257 31259 31271 31273 36914-36915 36936 36940 36943 36946 36948 36951 36955 36961 36967 36976 36979 37004 37009 37012-37013 37056 37091 37125-37127 37132 37136-37137 37140-37142 37145-37146 37158 37173 37184-37186 37196-37197 37212-37213 37248 37316 37328 37888-37890 37892-37893 37895 37901 37905 37907 37912 37915 37917-37919 37921-37922 37936 37940 37946 37951 37953-37955 37962-37965 37973-37975 37978 37980-37981 37988 37990-37991 37996 38000-38001 38022 38087 38144-38146 38154 38159 38166 38172 38175-38177 38181-38182 38184 38189 38191 38193 38197 38201 38205 38208 38211-38213 38215-38216 38222 38225 38228-38229 38231 38233 38242 38247 38253 38261 38272 38341 38352 38382 38746 38850 41102 41126-41130 41145-41146 41149 41452 41476-41478 41480 41482 41484 41486 41489 41492 41500 41508-41510 41522-41523 41528 41530-41532 41543 41546-41547 41563-41564 41569 41571 41574-41575 41577 41579 41589-41591 41596-41598 41612-41613 41616 41618-41619 41622 41624-41625 41627-41630 41652 41684 41686-41687 41696-41698 41712 41714-41715 41724 41726-41727 41734 41739 41741 41745 41748-41750 41757 41760 41762 41778 41783 41785 41789 41791 41794 41806 41812 41815 41819-41821 41831-41834 41836-41837 41839 41848 41850 41855 41868-41869 41871 41874-41877 41884 41887-41888 41890-41891 41893-41895 41900 41902-41903 41905-41908 41910-41912 41914-41915 41922 41924-41925 41927 41929 41931 41934-41935 41940-41942 41949-41951 42102 42123 42151 42157-42161 42168 42171-42172 42174 42199 42211 42213-42215 42227-42229 42231-42232 42234-42235 42290 42294 42301-42303 42311 42313-42315 42317-42319 42323 42326-42327 42330-42331 42338-42339 42341 42344 42346-42349 42351-42353 42355-42357 42364-42366 42369 42376 42379-42380 42382-42384 42387-42388 42391 42393-42395 42435-42436 42438 42449-42450 42456 42458-42459 42461-42463 42468 42470-42471 42489-42490 42492-42493 42495 42500-42502 42506 42508-42509 42512 42515-42517 42519 42529-42530 42539 42541 42543-42546 42624 42626-42627 42774-42775 42820-42822 42828 42830-42831 42839-42842 42844-42845 42847 42852 42854-42855 42865-42866 42868-42869 42871 42873-42875 42877 42972-42974 43080 43082-43083 43096-43098 43188-43190 43232-43233 43235 43316-43317 43319 43436 43439 43444-43446 43448-43450 43472-43473 43475 43480-43481 43483-43484 43486-43487 43491-43493 43495-43497 43501 43503 43505 43508-43510 43512-43513 43549-43551 43560-43561 43563-43565 43568 43570-43572 43574-43575 43580 43588-43589 43591-43593 43595 43605 43607-43610 43612-43613 43616 43619-43620 43623-43624 43626 43628 43630-43632 43639 43642 43653-43655 43657-43659 43663-43665 43668-43670 43672-43673 43677 43679 43682-43683 43685 43689-43693 43704 43707 43713 43715 43718 43722 43728 43753 43781 43783 43787 43789 43796 43798-43799 43801 43803 43805 43812 43825 43829 43845-43846 43856 44088-44090 44128-44130 44136-44137 44139-44142 44148-44149 44151 44156-44157 44159 44162-44166 44169 44171-44172 44174-44175 44180 44186-44187 44189-44190 44195-44198 44201 44204-44205 44207 44210 44213-44214 44216-44218 44221-44222 44226-44227 44229-44234 44244-44245 44247 44249 44251-44253 44255-44258 44267 44278 44329-44331 44345-44346 44348-44350 44380 44382-44383 44392-44394 44404-44405 44407-44410 44412 44416 44418-44422 44425 44436 44440 44445 44449 44460 44465 44468-44469 44481 44483 44485-44486 44489 44494 44498-44501 44527 44531 44549-44550 44556 44608 44610 44624 44877 44881 44887 44889 44895 47727 47730 47735 47738-47739 47741-47743 47765 47767 47777 47795 47798-47799 47802-47803 47805-47807 47811 47817-47819 47828 47830-47831 47837-47839 47848-47849 47851 47860 47863-47864 47866 47882https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/677/A59?format=asciiOpticaldefaultJ/A+A/677/A59/table3Overview of the 37 SigMA clusters in Sco-Cen, assigned to seven subregionsSimbadSimbad column added by the CDSmeta.ref.urlchar_RA.icrsRight ascension (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.raindexed_DE.icrsDeclination (ICRS) (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.decindexedrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSigMA[1/37] Membership label for each source (co-moving cluster identification number)meta.id;meta.mainintRegionSubregion (1)obs.fieldcharGroupGroup namemeta.idcharBstarBrightest star (2)meta.idcharNrNumber of starsmeta.numberintGLONMedian Galactic longitude (3)degpos.galactic.lonE_GLONUpper 1{sigma} error on GLONdegstat.error;stat.maxfloate_GLONLower 1{sigma} error on GLONdegstat.errorfloatGLATMedian Galactic latitude (3)degpos.galactic.latE_GLATUpper 1{sigma} error on GLAT (4)degstat.error;stat.maxfloate_GLATLower 1{sigma} error on GLAT (4)degstat.errorfloatplxMedian parallax (3)maspos.parallax;stat.medianfloatE_plxUpper 1{sigma} error on plx (4)masstat.error;stat.maxfloate_plxLower 1{sigma} error on plx (4)masstat.error;pos.parallaxfloatDistDistance (3)pcpos.distanceintE_DistUpper 1{sigma} error onpcstat.error;stat.maxinte_DistLower 1{sigma} error on Distpcstat.errorintXMedian X position (3)pcpos.distance;pos.cartesian.x;stat.medianintE_XUpper 1{sigma} error on X (4)pcstat.error;stat.maxinte_XLower 1{sigma} error on X (4)pcstat.error;pos.cartesian.xintYMedian Y position (3)pcpos.distance;pos.cartesian.y;stat.medianintE_YUpper 1{sigma} error on Y (4)pcstat.error;stat.maxinte_YLower 1{sigma} error on Y (4)pcstat.error;pos.cartesian.yintZMedian Z position (3)pcpos.distance;pos.cartesian.z;stat.medianintE_ZUpper 1{sigma} error on Z (4)pcstat.error;stat.maxinte_ZLower 1{sigma} error on Z (4)pcstat.error;src.redshiftintJ/A+A/677/A59/tablee1Sco-Cen cluster informatione_ZLower 1{sigma} Z uncertaintypcstat.error;src.redshiftE_XUpper 1{sigma} X uncertaintypcstat.error;stat.maxSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGaiaDR3Gaia DR3 unique source identifiermeta.id;meta.mainSigMA[1/37] Membership label for each source (co-moving cluster identification number)meta.idintstability[0/100] Source fidelity measure%stat.fit.goodnessfloatDistDistance to sourcepcpos.distancee_DistLower 1{sigma} distance uncertaintypcstat.errorE_DistUpper 1{sigma} distance uncertaintypcstat.error;stat.maxXGalactic Cartesian X positionpcpos.distance;pos.cartesian.x;pos.galactice_XLower 1{sigma} X uncertaintypcstat.error;pos.cartesian.xYGalactic Cartesian Y positionpcpos.distance;pos.cartesian.y;pos.galactice_YLower 1{sigma} Y uncertaintypcstat.error;pos.cartesian.yZGalactic Cartesian Z positionpcpos.distance;pos.cartesian.z;pos.galacticE_YUpper 1{sigma} Y uncertaintypcstat.error;stat.maxE_ZUpper 1{sigma} Z uncertaintypcstat.error;stat.maxVtRATangential velocity in RA directionkm/sphys.veloc.transversee_VtRALower 1{sigma} VtRA uncertaintykm/sstat.errorVtDETangential velocity in DE directionkm/sphys.veloc.transversee_VtDELower 1{sigma} VtDE uncertaintykm/sstat.errorE_VtRAUpper 1{sigma} VtRA uncertaintykm/sstat.error;stat.maxE_VtDEUpper 1{sigma} VtDE uncertaintykm/sstat.error;stat.maxVtRALSRTangential velocity (RA) in LSRkm/sphys.veloc.transverseVtDELSRTangential velocity (DE) in LSRkm/sphys.veloc.transverseRVEstimated radial velocitykm/sphys.veloc;pos.heliocentric_RAPositions from Gaia DR3 (right ascension part)degpos.eq.ra;meta.mainindexed_DEPositions from Gaia DR3 (declination part)degpos.eq.dec;meta.mainindexed