| DOI | Trouver le DOI : https://doi.org/10.1051/0004-6361/201118381 |
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| Auteur | Rechercher : Marino, A. F.; Rechercher : Milone, A. P.; Rechercher : Sneden, C.; Rechercher : Bergemann, M.; Rechercher : Kraft, R. P.; Rechercher : Wallerstein, G.; Rechercher : Cassisi, S.; Rechercher : Aparicio, A.; Rechercher : Asplund, M.; Rechercher : Bedin, R. L.; Rechercher : Hilker, M.; Rechercher : Lind, K.; Rechercher : Momany, Y.; Rechercher : Piotto, G.; Rechercher : Roederer, I. U.; Rechercher : Stetson, P. B.1; Rechercher : Zoccali, M. |
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| Affiliation | - Conseil national de recherches du Canada. Infrastructure scientifique nationale
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| Format | Texte, Article |
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| Résumé | We present an abundance analysis of 101 subgiant branch (SGB) stars in the globular cluster M 22. Using low-resolution FLAMES/GIRAFFE spectra we have determined abundances of the neutron-capture strontium and barium and the light element carbon. With these data we explore relationships between the observed SGB photometric split in this cluster and two stellar groups characterized by different contents of iron, slow neutron-capture process (s-process) elements, and the α element calcium, which we previously discovered in M 22’s red-giant stars. We show that the SGB stars correlate in chemical composition and the color–magnitude diagram position. The stars with higher metallicity and relative s-process abundances define a fainter SGB, while stars with lower metallicity and s-process content reside on a relatively brighter SGB. This result has implications for the relative ages of the two stellar groups of M 22. In particular, it is inconsistent with a broad spread in ages of the two SGBs. By accounting for the chemical content of the two stellar groups, isochrone fitting of the double SGB suggests that their agesare not different by more than ~300 Myr. |
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| Date de publication | 2012-04-20 |
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| Dans | |
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| Langue | anglais |
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| Publications évaluées par des pairs | Oui |
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| Numéro NPARC | 21268986 |
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| Exporter la notice | Exporter en format RIS |
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| Signaler une correction | Signaler une correction (s'ouvre dans un nouvel onglet) |
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| Identificateur de l’enregistrement | 566d8bb5-a5c3-4288-85a1-c7b68b0a1853 |
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| Enregistrement créé | 2013-11-29 |
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| Enregistrement modifié | 2020-04-21 |
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