J/ApJ/772/148ivo://CDS.VizieR/J/ApJ/772/148doi:10.26093/cds/vizier.17720148CDSLovisi L.Mucciarelli A.Lanzoni B.Ferraro F.R.Dalessandro E.,Monaco L.2017-06-19T07:58:00Z2015-03-09T13:40:03ZCDS support team

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

cds-question@unistra.frglobular-star-clusterschemical-abundancesradial-velocitygiant-starsWe present spectroscopic observations acquired with FLAMES and XSHOOTER at the Very Large Telescope for a sample of 15 blue straggler stars (BSSs) in the globular cluster (GC) M30 (NGC 7099). The targets have been selected to sample the two BSS sequences discovered, with seven BSSs along the blue sequence and eight along the red one. No difference in the kinematical properties of the two groups of BSSs has been found. In particular, almost all the observed BSSs have projected rotational velocities lower than ~30 km/s, with only one (blue) fast rotating BSS (>90km/s), identified as a W UMa binary. This rotational velocity distribution is similar to those obtained in 47 Tucanae and NGC 6397, while M4 remains the only GC studied so far that harbors a large fraction of fast rotating BSSs. All stars hotter than ~7800K (regardless of the parent BSS sequence) show iron abundances larger than those measured from normal cluster stars, with a clear-cut trend with the effective temperature. This behavior suggests that particle transport mechanisms driven by radiative levitation occur in the photosphere of these stars, as already observed for the BSSs in NGC 6397. Finally, four BSSs belonging to the red sequence (not affected by radiative levitation) show a strong depletion of [O/Fe], with respect to the abundance measured in red giant branch and horizontal branch stars. This O-depletion is compatible with the chemical signature expected in BSSs formed by mass-transfer processes in binary systems, in agreement with the mechanism proposed for the formation of BSSs in the red sequence.2013ApJ...772..148Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/772/148CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toVI/113 : Evolutionary models of Population II stars (Cariulo+, 2004)VII/202 : Globular Clusters in the Milky Way (Harris, 1997)J/ApJ/754/91 : Abundances and velocities of NGC 6397 stars (Lovisi+, 2012)J/MNRAS/412/81 : Lithium abundance in M4 red giants (Mucciarelli+, 2011)J/A+A/523/A71 : A and F stars abundances in the Hyades (Gebran+, 2010)J/ApJ/705/328 : Abundance measurements in Sculptor dSph (Kirby+, 2009)J/ApJ/704/750 : Rotational behavior of metal-poor stars (Cortes+, 2009)J/A+A/505/139 : Abundances of red giants in 17 GCs (Carretta+, 2009)J/A+A/505/117 : Abundances of red giants in 15 GCs (Carretta+, 2009)J/A+A/483/183 : Catalogue of Blue Stragglers (Moretti+, 2008)J/A+A/462/L9 : Radial velocities in NGC 7099 (Scarpa+, 2007)J/AJ/130/2140 : Abundances & velocities in globular clusters (Pritzl+, 2005)J/MNRAS/351/1204 : IR Phot. of 10 Galactic Globular Clusters (Valenti+, 2004)J/ApJ/518/262 : CCD VIc Photometry of M30 Stars (Sandquist+, 1999)J/AJ/116/1757 : M30 UBV photometry (Guhathakurta+, 1998)J/AJ/109/218 : Catalogue of globular cluster profiles (Trager+ 1995)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/772/148https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/772/148http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/772/148https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/772/148https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/772/148http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/772/148GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/772/148/m30stars (Parameters of blue straggler star (BSS) and red giant branch (RGB) and horizontal branch (HB) stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/772/148/m30stars?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/772/148/m30stars?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/772/148/m30stars?GETtext/xml+votable180.050000true325.0986591-23.16353260.0055555555555555566/48434 48440https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/772/148?format=asciiOpticaldefaultJ/ApJ/772/148/m30starsParameters of blue straggler star (BSS) and red giant branch (RGB) and horizontal branch (HB) starsTypeSimbad column added by the CDSmeta.code.classchar[LML2013][10201736/924000008] Source identifiermeta.id;meta.mainlongprimaryf_[LML2013][RB] Read of Blue sequence (1)meta.codecharRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.mainVmag[14.3/18.3] V band magnitudemagphot.mag;em.opt.VfloatImag[13.3/17.9] I band magnitudemagphot.mag;em.opt.IfloatTeff[4943/11000] Effective temperatureKphys.temperature.effectiveintlogg[1.9/4.4] Log of the surface gravitylog(cm.s**-2)phys.gravityfloatVt? Microturbulent velocitykm/sphys.velocfloatnullableRVel[-193/-174]? Radial velocitykm/sphys.veloc;pos.heliocentricfloatnullablee_RVel[0.2/3.3]? Uncertainty in RVelkm/sstat.error;spect.dopplerVelocfloatnullablel_vsin(i)Limit flag on vsin(i)meta.code.errorcharvsin(i)[0/90] Rotational velocitykm/sphys.veloc.rotatinte_vsin(i)[1/4]? Uncertainty in vsin(i)km/sstat.errorintnullablel_[Fe/H]Limit flag on [Fe/H]meta.code.error;phys.abund.Fechar[Fe/H][-2.5/-0.6]? Metallicitylog(Sun)phys.abund.Zfloatnullablee_[Fe/H][0.02/0.25]? Uncertainty in [Fe/H]log(Sun)stat.error;phys.abund.Fefloatnullablen_[Fe/H][*] No FeII line detected (2)meta.notecharl_[Mg/H]Limit flag on [Mg/H]meta.code.error;phys.abundchar[Mg/H][-2.5/-1.2]? The [Mg/H] abundancelog(Sun)phys.abundfloatnullablee_[Mg/H][0.05/0.2]? Uncertainty in [Mg/H]log(Sun)stat.error;phys.abundfloatnullable[Ti/H][-2.3/-1.1]? The [Ti/H] abundancelog(Sun)phys.abundfloatnullablee_[Ti/H][0.04/0.2]? Uncertainty in [Ti/H]log(Sun)stat.error;phys.abundfloatnullablel_[O/H]Limit flag on [O/H]meta.code.error;phys.abundchar[O/H][-2.9/-1.4]? The [O/H] abundancelog(Sun)phys.abundfloatnullablee_[O/H]? Uncertainty in [O/H]log(Sun)stat.error;phys.abundfloatnullableNotesNote (3)meta.notecharSimbadSimbad column added by the CDSmeta.ref.urlchar