J/MNRAS/400/1479ivo://CDS.VizieR/J/MNRAS/400/1479doi:10.26093/cds/vizier.74001479CDSSana H.Gosset E.Evans C.J.2024-07-09T20:16:08Z2010-04-26T14:09:18ZCDS support team

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

cds-question@unistra.fropen-star-clustersspectroscopic-binary-starso-starsradial-velocityBased on a set of over 100 medium- to high-resolution optical spectra collected from 2003 to 2009, we investigate the properties of the O-type star population in NGC 6611 in the core of the Eagle Nebula (M16). Using a much more extended data set than previously available, we revise the spectral classification and multiplicity status of the nine O-type stars in our sample. We confirm two suspected binaries and derive the first SB2 orbital solutions for two systems. We further report that two other objects are displaying a composite spectrum, suggesting possible long- period binaries. Our analysis is supported by a set of Monte-Carlo simulations, allowing us to estimate the detection biases of our campaign and showing that the latter do not affect our conclusions. The absolute minimal binary fraction in our sample is f_min_=0.44 but could be as high as 0.67 if all the binary candidates are confirmed. As in NGC 6231 (see Paper I, Sana et al., Cat. J/MNRAS/386/447), up to 75% of the O star population in NGC 6611 are found in an O+OB system, thus implicitly excluding random pairing from a classical IMF as a process to describe the companion association in massive binaries. No statistical difference could be further identified in the binary fraction, mass-ratio and period distributions between NGC 6231 and NGC 6611, despite the difference in age and environment of the two clusters.2009MNRAS.400.1479Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/400/1479CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/386/447 : RV catalogue of O-type stars in NGC 6231 (Sana+, 2008)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/400/1479https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/400/1479http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/400/1479https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/400/1479https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/400/1479http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/400/1479GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/400/1479/stars (Star list)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/400/1479/stars?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/400/1479/stars?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/400/1479/stars?GETtext/xml+votable180.050000true274.63625-13.7533330.0055555555555555566/29463https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/400/1479?format=asciiOpticaldefaultJ/MNRAS/400/1479/starsStar listrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharprimarym_Name[psc] Component (primary/secondary/composite)meta.code.multipcharRAJ2000Simbad right ascension (J2000) of the systempos.eq.ra;meta.mainDEJ2000Simbad declination sign (J2000) of the systempos.eq.dec;meta.mainSpTypeSpectral type from table4 of the papersrc.spTypecharSimbadSimbad column added by the CDScharJ/MNRAS/400/1479/table3RV data for O stars in NGC 6611recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharm_Name[psc] Component (primary/secondary/composite)meta.code.multipcharHJDHeliocentric Julian Datedtime.epochdoubleInst[a-e] Instrument Setup Code (1)meta.code;instr.setupchar4026? RV measured on HeI4026 (r.w. 4026.072)(2)km/sspect.dopplerVelocfloatnullable4089? RV measured on SiIV4089 (r.w. 4088.863)(2)km/sspect.dopplerVelocfloatnullable4144? RV measured on HeI4144 (r.w. 4143.759)(2)km/sspect.dopplerVelocfloatnullable4388? RV measured on HeI4388 (r.w. 4387.928)(2)km/sspect.dopplerVelocfloatnullable4471? RV measured on HeI4471 (r.w. 4471.512)(2)km/sspect.dopplerVelocfloatnullable4481? RV measured on MgII4481 (r.w. 4481.228)(2)km/sspect.dopplerVelocfloatnullable4542? RV measured on HeII4542 (r.w. 4541.590)(2)km/sspect.dopplerVelocfloatnullable4686? RV measured on HeII5686 (r.w. 4685.682)(2)km/sspect.dopplerVelocfloatnullable4921? RV measured on HeI4921 (r.w. 4921.929)(2)km/sspect.dopplerVelocfloatnullable5412? RV measured on HeII5412 (r.w. 5411.620)(2)km/sspect.dopplerVelocfloatnullable5876? RV measured on HeI5876 (r.w. 5875.620)(2)km/sspect.dopplerVelocfloatnullable7065? RV measured on HeI7065 (r.w. 7065.190)(2)km/sspect.dopplerVelocfloatnullable