J/A+A/333/897ivo://CDS.VizieR/J/A+A/333/897doi:10.26093/cds/vizier.33330897CDSRaboud D.Mermilliod J.-C.2017-11-28T13:21:50Z2007-07-09T16:52:57ZCDS support team

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

cds-question@unistra.fropen-star-clustersphotometrystellar-distancestellar-massesOn the basis of the best available member list and duplicity information, we have studied the radial structure of Praesepe and of the very young open cluster NGC 6231. We have found mass segregation among the cluster members and between binaries and single stars, which is explained by the greater average mass of the multiple systems. However, the degree of mass segregation for stars between 1.5 and 2.3M_{sun}_ is less pronounced in Praesepe than in the Pleiades. Furthermore, mass segregation is already present in the very young open cluster NGC 6231 although this cluster is likely still not dynamically relaxed. We discuss the implications of these results and propose a qualitative scenario for the evolution of mass segregation in open clusters. In Praesepe the mass function of single stars and primaries appears to be significantly different, like in the Pleiades. We observe an absence of ellipticity of the outer part of Praesepe.1998A&A...333..897Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/333/897CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/325/167 : Geneva photometry in NGC 6231 (Raboud+ 1997)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/333/897https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/333/897http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/333/897https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/333/897https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/333/897http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/333/897GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/333/897/table2 (Member stars in Praesepe)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/333/897/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/333/897/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/333/897/table2?GETtext/xml+votable180.050000true129.19411219.76230.005555555555555556Cone search capability for table J/A+A/333/897/table3 (Member stars in NGC 6231)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/333/897/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/333/897/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/333/897/table3?GETtext/xml+votable180.050000true253.5145833-41.71441670.0055555555555555565/1171 1174 6/4678 4689-4691 4700 4702 4705 4709 4720-4722 4724-4725 42383 42392 42394-42396 42405 42416-42417https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/333/897?format=asciiOpticaldefaultJ/A+A/333/897/table2Member stars in PraeseperecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintKWStar identification (Cl* NGC 2632 KW NNN in Simbad database)meta.id;meta.mainintVmagV magnitudemagphot.mag;em.opt.VfloatB-VB-V colour indexmagphot.color;em.opt.B;em.opt.VfloatXposx coordinate (1)arcminpos.cartesian.x;instr.detfloatYposy coordinate (1)arcminpos.cartesian.y;instr.detfloatDistDistance from the cluster centerarcminpos.angDistancefloatMult[1/3] Multiplicity status (G1)meta.code.multipintTypeBinary type (G2)src.classcharMassTotTotal masssolMassphys.massfloatMassAComponent A masssolMassphys.massfloatMassB? Component B masssolMassphys.massfloatnullableMassC? Component C masssolMassphys.massfloatnullable_RAPosition, from Simbad for Klein-Wassink stars (KW<=577), and from (Xpos,Ypos) for other stars (right ascension part)degpos.eq.ra;meta.main_DEPosition, from Simbad for Klein-Wassink stars (KW<=577), and from (Xpos,Ypos) for other stars (declination part)degpos.eq.dec;meta.mainJ/A+A/333/897/table3Member stars in NGC 6231recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNGC6231Star identification (NGC 6231 NNN in Simbad database)meta.id;meta.mainintVmagV magnitudemagphot.mag;em.opt.VfloatcolColour ((B-V)J, (B-V)G or b-y) (1)magphot.colorfloatphotPhotometry used (Gen, UBV or uvby)meta.id;photcharXposx coordinate (2)arcminpos.cartesian.x;instr.detfloatYposy coordinate (2)arcminpos.cartesian.y;instr.detfloatDistDistance from the cluster centerarcminpos.angDistancefloatMult[1/2] Multiplicity status (G1)meta.code.multipintTypeBinary type (G1)src.classcharMassTotTotal masssolMassphys.massfloatMassA? Component A masssolMassphys.massfloatnullableMassB? Component B masssolMassphys.massfloatnullableSimbadSimbad column added by the CDSchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main