J/A+A/528/A127ivo://CDS.VizieR/J/A+A/528/A127doi:10.26093/cds/vizier.35280127CDSMoni Bidin C.Villanova S.Piotto G.Momany Y.2017-09-22T16:15:43Z2011-09-20T13:47:34ZCDS support team

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

cds-question@unistra.frglobular-star-clustersspectroscopic-binary-starshorizontal-branch-starsThe formation mechanism of hot horizontal branch (HB) stars is still one of the most uncertain points of stellar evolution theories. In the past decade, models based on their binary origin have been very successful in reproducing the properties of field subdwarf-B stars, but the observations of their analogues in globular clusters has posed new problems. In addition, the discovery of multiple populations offered an appealing alternative scenario for the formation of these stars. We search for binaries of period P<=200days among a sample of 83 blue horizontal branch stars (Teff=12000-22000K) in NGC 2808, a cluster known to host three distinct stellar populations and a multimodal horizontal branch. The final sample, after the rejection of stars with incomplete observations or poor quality data, consists of 64 targets. The radial velocity of the targets was measured in fourteen epochs, spanning a temporal interval of ~75days. The significant variations were identified by means of a detailed error analysis and a statistical study.2011A&A...528A.127Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/528/A127CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+AS/84/59 : Photometry of NGC 2808 (Ferraro+, 1990)J/ApJ/562/368 : UV photometry in NGC 2808 (Brown+, 2001)J/A+A/413/343 : RGB stars in NGC 2808 (Cacciari+, 2004)J/ApJ/625/156 : FUV-NUV observations of NGC 2808 (Dieball+, 2005)J/AJ/131/1766 : Abundances and equivalent widths in NGC 2808 (Carretta, 2006)J/A+A/490/641 : X-ray sources toward NGC 2808 (Servillat+, 2008)J/A+A/480/397 : XMM observations of NGC 2808 and NGC 4372 (Servillat+, 2008)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/528/A127https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/528/A127http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/528/A127https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/528/A127https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/528/A127http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/528/A127GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/528/A127/table3 (Data of program stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/528/A127/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/528/A127/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/528/A127/table3?GETtext/xml+votable180.050000true137.9245417-64.70158330.0055555555555555566/37294 376363.322582951404819e-19 3.852589004194616e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/528/A127?format=asciiOpticaldefaultJ/A+A/528/A127/table3Data of program starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqSequential number (<[MVP2011] NNNNN> in Simbad)meta.recordintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainVmagV magnitudemagphot.mag;em.opt.VfloatU-VU-V colour indexmagphot.color;em.opt.U;em.opt.VfloatTeffEffective temperatureKphys.temperature.effectiveintl_<RV>[~] Limit flag on <RV>meta.code.errorchar<RV>? Weighted average radial velocitykm/sspect.dopplerVeloc;stat.meanfloatnullablee_<RV>? rms uncertainty on <RV>km/sstat.errorfloatnullableDmax? Maximum residual of {Delta}_i_=(RV_i_-<RV>)/{sigma}_i_km/sstat.fit.residual;phys.velocfloatnullableSimbadSimbad column added by the CDSmeta.refchar