| Texto completo | |
| Autor(es): Mostrar menos - |
Oliveira, R. A. P.
;
Souza, S. O.
;
Kerber, L. O.
;
Barbuy, B.
;
Ortolani, S.
;
Piotto, G.
;
Nardiello, D.
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Perez-Villegas, A.
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Maia, F. F. S.
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Bica, E.
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Cassisi, S.
;
D'Antona, F.
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Lagioia, E. P.
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Libralato, M.
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Milone, A. P.
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Anderson, J.
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Aparicio, A.
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Bedin, L. R.
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Brown, T. M.
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King, I. R.
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Marino, A. F.
;
Pietrinferni, A.
;
Renzini, A.
;
Sarajedini, A.
;
Van der Marel, R.
;
Vesperini, E.
Número total de Autores: 26
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| Tipo de documento: | Artigo Científico |
| Fonte: | ASTROPHYSICAL JOURNAL; v. 891, n. 1, p. 20-pg., 2020-03-01. |
| Resumo | |
In the present work we analyzed seven globular clusters (GCs) selected from their location in the Galactic bulge and with metallicity values in the range -1.30 less than or similar to [Fe/H] less than or similar to -0.50. The aim of this work is first to derive cluster ages assuming single stellar populations and second to identify the stars from first (1G) and second generations (2G) from the main sequence, subgiant, and red giant branches, and to derive their age differences. Based on a combination of UV and optical filters used in this project, we apply the Gaussian mixture models to distinguish the multiple stellar populations. Applying statistical isochrone fitting, we derive self-consistent ages, distances, metallicities, and reddening values for the sample clusters. An average age of 12.3 0.4 Gyr was obtained both using DSED and BaSTI (accounting atomic diffusion effects) isochrones, without a clear distinction between the moderately metal-poor and the more metal-rich bulge clusters, except for NGC 6717 and the inner halo NGC 6362 with similar to 13.5 Gyr. We derived a weighted mean age difference between the multiple populations hosted by each GC of 41 170 Myr adopting canonical He abundances; whereas for higher He in 2G stars, this difference reduces to 17 170 Myr, but with individual uncertainties of 500 Myr. (AU) | |
| Processo FAPESP: | 17/15893-1 - Órbitas de aglomerados globulares do bojo: formação e evolução da Via Láctea |
| Beneficiário: | Maria de Los Angeles Perez Villegas |
| Modalidade de apoio: | Bolsas no Brasil - Pós-Doutorado |
| Processo FAPESP: | 18/22181-0 - Gradientes de idade e metalicidade dos aglomerados estelares da Ponte de Magalhães |
| Beneficiário: | Raphael Augusto Pereira de Oliveira |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |
| Processo FAPESP: | 18/22044-3 - Aglomerados globulares do bojo: relíquias da formação e evolução da galáxia |
| Beneficiário: | Stefano Oliveira de Souza |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado Direto |