J/ApJ/881/104ivo://CDS.VizieR/J/ApJ/881/104doi:10.26093/cds/vizier.18810104CDSMagurno+Magurno D.Sneden C.Bono G.Braga V.F.Mateo M.,Persson S.E.Preston G.Thevenin F.da Silva R.Dall'Ora M.,Fabrizio M.Ferraro I.Fiorentino G.Iannicola G.Inno L.Marengo M.,Marinoni S.Marrese P.M.Martinez-Vazquez C.E.Matsunaga N.Monelli M.,Neeley J.R.Nonino M.Walker A.R.2022-06-03T08:24:07Z2021-01-26T13:24:13ZCDS support team

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

cds-question@unistra.frglobular-star-clustersvariable-starsvisible-astronomyspectroscopymetallicityradial-velocityWe present a detailed spectroscopic analysis of RR Lyrae (RRL) variables in the globular cluster NGC5139 ({omega} Cen). We collected optical (4580-5330{AA}), high-resolution (R~34000), high signal-to-noise ratio (~200) spectra for 113 RRLs with the multifiber spectrograph M2FS at the Magellan/Clay Telescope at Las Campanas Observatory. We also analyzed high- resolution (R~26000) spectra for 122 RRLs collected with FLAMES/GIRAFFE at the Very Large Telescope, available in the ESO archive. The current sample doubles the literature abundances of cluster and field RRLs in the Milky Way based on high-resolution spectra. Equivalent-width measurements were used to estimate atmospheric parameters, iron, and abundance ratios for {alpha} (Mg, Ca, Ti), iron peak (Sc, Cr, Ni, Zn), and s-process (Y) elements. We confirm that {omega}Cen is a complex cluster, characterized by a large spread in the iron content: -2.58<~[Fe/H]<~-0.85. We estimated the average cluster abundance as <[Fe/H]>=-1.80{+/-}0.03, with {sigma}=0.33dex. Our findings also suggest that two different RRL populations coexist in the cluster. The former is more metal-poor ([Fe/H]<~-1.5), with almost solar abundance of Y. The latter is less numerous, more metal-rich, and yttrium enhanced ([Y/Fe]>~0.4). This peculiar bimodal enrichment only shows up in the s-process element, and it is not observed among lighter elements, whose [X/Fe] ratios are typical for Galactic globular clusters.2019ApJ...881..104Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/881/104CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/110/2319 : Abundances in RR Lyr variables (Clementini+ 1995)J/ApJ/462/241 : Ca abundance for Omega Cen red giants (Norris+ 1996)J/AJ/119/1824 : Caby photometry of {Omega} Centauri (Rey+, 2000)J/A+A/424/1101 : Variable Stars in the field of {omega} Cen (Kaluzny+, 2004)J/AJ/130/2140 : Abundances and velocities globular clusters (Pritzl+, 2005)J/MNRAS/370/1979 : JHKs photometry of T2Cs globular clusters (Matsunaga+, 2006)J/A+A/445/503 : Radial velocities in Omega Cen (NGC5139) (Reijns+, 2006)J/ApJ/640/L43 : Metallicities of RR Lyrae stars in Omega Cen (Sollima+,2006)J/ApJ/663/1021 : Log of {omega} Cen scientific images (Castellani+, 2007)J/ApJ/667/1267 : CrI transition probabilities (Sobeck+, 2007)J/AJ/133/1447 : Light curves of variable stars {omega}Cen (Weldrake+, 2007)J/AJ/136/506 : Radial velocities {omega}Centauri members (Da Costa+, 2008)J/ApJ/706/1277 : Stromgren photometry in {omega} Cen (Calamida+, 2009)J/A+A/505/139 : Abund. red giants in 17 globular clusters (Carretta+, 2009)J/PASP/121/1378 : Positions variable stars in globular clusters (Samus+, 2009)J/ApJ/712/L21 : Calcium abundances in 17 globular clusters (Carretta+, 2010)J/AJ/140/1694 : Abundances of non-variable red and blue HB stars (For+,2010)J/AN/331/474 : Abundances of metal-poor stars (Frebel, 2010)J/ApJ/708/560 : Spectroscopy of UMa II and Coma Ber (Frebel+, 2010)J/ApJ/722/1373 : {omega} Centauri giants abundances (Johnson+, 2010)J/A+A/523/A17 : Individual stars in Fornax dSph center (Letarte+, 2010)J/ApJS/197/29 : Chemical compositions of 11 RR Lyrae (For+, 2011)J/ApJ/731/64 : Spectroscopy of 300 RGBs in {omega} Cen (Marino+, 2011)J/A+A/534/A53 : Equivalent widths of 18 subgiant {omega}Cen (Pancino+, 2011)J/AJ/144/114 : Radial velocities of 6 field RR Lyrae (Sesar+, 2012)J/ApJ/751/102 : Equivalent widths of 9 RGB in Carina dSph (Venn+, 2012)J/ApJS/208/27 : Sun and HD 84937 TiII log(gf) and abundances (Wood+, 2013)J/ApJS/215/23 : FeI radiative lifetime & branching fract. (Den Hartog+,2014)J/ApJ/782/59 : Abund. of 8 RRLyrae subclass C variable stars (Govea+, 2014)J/MNRAS/441/3127 : FeI oscillator strengths for Gaia-ESO (Ruffoni+, 2014)J/ApJ/791/107 : Parameters of NGC 5139 SGBs stars (Villanova+, 2014)J/ApJS/211/20 : NiI transition probability measurements (Wood+, 2014)J/A+A/576/A30 : NIR light-curve templates classical Cepheids (Inno+, 2015)J/MNRAS/447/2404 : Equivalent width of 21 RR Lyrae stars (Pancino+, 2015)J/AJ/152/170 : RRLs in globulars.IV. UBVRI photom. Omega Cen (Braga+, 2016)J/AJ/154/150 : Spectroscopy of RGB stars in {omega} Centauri (An+, 2017)J/ApJS/228/10 : Transition probabilities 183 lines of CrII (Lawler+, 2017)J/ApJ/848/68 : Abundance & RVs of stable & Blazhko RRc stars (Sneden+,2017)J/AJ/155/137 : RRLs globulars.V. {omega}Centauri NIR photom. (Braga+, 2018)J/ApJ/864/57 : Abundances of field & GC RR Lyrae.I. NGC3201 (Magurno+,2018)J/A+A/618/A134 : Omega Cen lower red giant stars abund. (Mucciarelli+, 2018)J/ApJ/870/115 : Reddening, dist. modulus & Fe/H of RRLs in wCen (Bono+,2019)http://www.nist.gov/pml/asd : NIST Atomic Spectra Database (Kramida+, 2018)http://vald.astro.uu.se/ : VALD database (Ryabchikova+, 2015)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/881/104https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/881/104http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/881/104https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/881/104https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/881/104http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/881/104GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/881/104/table1 (Photometric parameters and radial velocities for the stars in {omega}Cen, collected with M2FS.)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/881/104/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/881/104/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/881/104/table1?GETtext/xml+votable180.050000true201.5539167-47.40533330.0055555555555555566/43225 43227https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/881/104?format=asciiOpticaldefaultJ/ApJ/881/104/table1Photometric parameters and radial velocities for the stars in {omega}Cen, collected with M2FS.SimbadNameSimbad column added by the CDSmeta.idcharnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDStar identificationmeta.id;meta.maincharprimaryRAJ2000[13/13] Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000[47/47] Degree of Declination (J2000)pos.eq.dec;meta.mainPer[0.253/1.013] Perioddtime.perioddoubleHJD[7077/7126] Heliocentric Julian Date of observing epoch; HJD-2450000dtime.epochdoublePhase[0.01/1]? Observing phasetime.phasefloatnullableTypePulsation category; 44 RRab, 68 RRc or 1 RRd (1)meta.codecharf_Type[*] Asterisk marks Blazhko RRLs (19 occurrences)meta.codecharVmag[14.05/14.83] Mean V band magnitudemagphot.mag;em.opt.VfloatVamp[0.04/1.27] V band amplitudemagsrc.var.amplitudefloatRVel[173/264] Radial velocitykm/sphys.veloc;pos.heliocentricfloatFeHIron abundance for this star (link to table 6)meta.ref.urlcharAbundOther abundance for this star (link to table 8)meta.ref.urlcharJ/ApJ/881/104/table6Iron abundances for the considered samples of {omega}Cen RR Lyrae.SimbadNameSimbad column added by the CDSmeta.idcharnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDStar identificationmeta.id;meta.mainchar[Fe/H]EW[-2.53/-0.85]? The [Fe/H] for M2FS with EW methodphys.abund.Fefloatnullablee_[Fe/H]EW[0.01/0.15]? Uncertainty in [Fe/H]EWstat.error;spect.line.eqWidthfloatnullable[Fe/H]PAP[-2.58/-1.34]? The [Fe/H] for M2FS with PAP methodphys.abund.Fefloatnullablee_[Fe/H]PAP[0.02/0.52]? Uncertainty in [Fe/H]PAPstat.error;phys.abund.Fefloatnullable[FE/H]GIR[-2.14/-0.76]? GIRAFFE measured [Fe/H]phys.abund.Fefloatnullablee_[FE/H]GIR[0.2/0.53]? Uncertainty in [FE/H]GIRstat.error;phys.abund.Fefloatnullablen[1/7]? Multiplicity of GIRAFFE measurementsmeta.code.multipintnullable[Fe/H][-2.58/-0.85] The total [Fe/H] (1)phys.abund.Fefloate_[Fe/H][0.01/0.53] Uncertainty in [Fe/H]totstat.error;phys.abund.FefloatJ/ApJ/881/104/table8The {alpha}, iron-peak, and s-process element abundances for the considered samples of {omega}Cen RRLs collected with M2FSrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDStar identificationmeta.id;meta.mainchar[Mg/Fe][-0.07/0.95]? The [Mg/Fe] abundance ratiophys.abund;arith.ratiofloatnullablee_[Mg/Fe][0.03/0.28]? Uncertainty in [Mg/Fe]stat.error;phys.abundfloatnullable[Ca/Fe][0.17/0.63]? The [Ca/Fe] abundance ratiophys.abund;arith.ratiofloatnullablee_[Ca/Fe][0.1/0.1]? Uncertainty in [Ca/Fe]stat.error;phys.abundfloatnullable[Ti/Fe][-0.0/0.9]? The [Ti/Fe] abundance ratiophys.abund;arith.ratiofloatnullablee_[Ti/Fe][0.02/0.24]? Uncertainty in [Ti/Fe]stat.error;phys.abundfloatnullable[a/Fe][0.15/0.54]? The [{alpha}/Fe] abundance ratio (1)phys.abund;arith.ratiofloatnullablee_[a/Fe][0.06/0.14]? Uncertainty in [a/Fe]stat.error;phys.abundfloatnullable[Sc/Fe][-0.4/0.66]? The [Sc/Fe] abundance ratiophys.abund;arith.ratiofloatnullablee_[Sc/Fe][0.0/0.22]? Uncertainty in [Sc/Fe]stat.error;phys.abundfloatnullable[Cr/Fe][-0.34/0.57]? The [Cr/Fe] abundance ratiophys.abund;arith.ratiofloatnullablee_[Cr/Fe][0.02/0.15]? Uncertainty in [Cr/Fe]stat.error;phys.abundfloatnullable[Ni/Fe][-0.34/0.33]? The [Ni/Fe] abundance ratiophys.abund;arith.ratiofloatnullablee_[Ni/Fe][0.03/0.2]? Uncertainty in [Ni/Fe]stat.error;phys.abundfloatnullable[Zn/Fe][0.1/0.41]? The [Zn/Fe] abundance ratiophys.abund;arith.ratiofloatnullablee_[Zn/Fe][0.01/0.16]? Uncertainty in [Zn/Fe]stat.error;phys.abundfloatnullable[Y/Fe][-0.21/1.11]? The [Y/Fe] abundance ratiophys.abund;arith.ratiofloatnullablee_[Y/Fe][0.0/0.21]? Uncertainty in [Y/Fe]stat.error;phys.abundfloatnullableJ/ApJ/881/104/table2Line list and atomic parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintlambda[4589/5326] Wavelength ({AA})0.1nmem.wldoubleSpeciesSpecies identifier (1)meta.id;meta.maincharExPot[0/4.4] Excitation potentialeVphys.atmol.excitationfloatloggf[-4.12/0.57] log oscillator strengthphys.atmol.oscStrengthfloat