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dc.contributor.authorCoelho, Paulapt_BR
dc.contributor.authorBarbuy, Beatrizpt_BR
dc.contributor.authorPerrin, Marie-Noelpt_BR
dc.contributor.authorIdiart, Thais Eunice Pirespt_BR
dc.contributor.authorSchiavon, Ricardo P.pt_BR
dc.contributor.authorOrtolani, Sergiopt_BR
dc.contributor.authorBica, Eduardo Luiz Damianipt_BR
dc.date.accessioned2014-07-24T02:04:19Zpt_BR
dc.date.issued2001pt_BR
dc.identifier.issn0004-6361pt_BR
dc.identifier.urihttp://hdl.handle.net/10183/98500pt_BR
dc.description.abstractLow resolution spectra of 23 stars towards the bulge globular clusters NGC 6528 and NGC 6553 are analysed. Radial velocities and atmospheric parameters are derived in order to check their membership in the clusters. Effective temperatures were obtained from photometric data for stars with Teff > 3800 K, whereas for cooler stars, they were derived from equivalent widths of TiO bands. Calibrations of W(TiO) as a function of stellar parameters based on a grid of synthetic spectra are presented. Metallicities were derived from a comparison of the observed spectra to a grid of synthetic spectra. The sample comprises evolutionary stages from the Red Giant Branch to the Horizontal Branch, with parameters in the range 3200 <_ Teff <_ 5000 K and −0.5 <_ log g <_ 2.4. The mean metallicities obtained for NGC 6528 and NGC 6553 are [Fe/H] ≈ −0.5 and −0.7, in both cases with [Mg/Fe] = +0.3; assuming the same overabundance for the α elements O, Mg, Si, S, Ca and Ti, this gives [Z/ZΘ] = −0.25 and −0.45. Membership verification by means of low resolution spectra is a crucial step in preparing targets for high resolution spectroscopy with 8 m class telescopes.en
dc.format.mimetypeapplication/pdfpt_BR
dc.language.isoengpt_BR
dc.relation.ispartofAstronomy and astrophysics. Les Ulis. Vol. 376, no. 1 (Sept. 2001), p. 136-143pt_BR
dc.rightsOpen Accessen
dc.subjectClusters: globular: NGC 6528, NGC 6553en
dc.subjectAglomerados estelares globularespt_BR
dc.subjectComposicao estelarpt_BR
dc.subjectStars: abundancesen
dc.subjectEspectros estelarespt_BR
dc.titleMembership of 23 stars towards the bulge globular clusters NGC 6528 and NGC 6553pt_BR
dc.typeArtigo de periódicopt_BR
dc.identifier.nrb000311377pt_BR
dc.type.originEstrangeiropt_BR


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