The Hubble Space Telescope UV Legacy Survey of Galactic Globular Clusters. XX. Ages of Single and Multiple Stellar Populations in Seven Bulge Globular Clusters

Autor(es):Mostrar menos -

Oliveira, R. A. P. ^[1] ; Souza, S. O. ^[1] ; Kerber, L. O. ^{[1, 2]} ; Barbuy, B. ^[1] ; Ortolani, S. ^{[3, 4]} ; Piotto, G. ^{[3, 4]} ; Nardiello, D. ^{[3, 5, 4]} ; Perez-Villegas, A. ^[1] ; Maia, F. F. S. ^[6] ; Bica, E. ^[7] ; Cassisi, S. ^{[8, 9]} ; D'Antona, F. ^[10] ; Lagioia, E. P. ^{[3, 4]} ; Libralato, M. ^[11] ; Milone, A. P. ^{[3, 4]} ; Anderson, J. ^[11] ; Aparicio, A. ^{[12, 13]} ; Bedin, L. R. ^[4] ; Brown, T. M. ^[11] ; King, I. R. ^[14] ; Marino, A. F. ^[3] ; Pietrinferni, A. ^[9] ; Renzini, A. ^[4] ; Sarajedini, A. ^[15] ; Van der Marel, R. ^{[11, 16]} ; Vesperini, E. ^[17]

Afiliação do(s) autor(es):Mostrar menos -

^[1] Univ Sao Paulo, IAG, Rua Matao 1226, Cidade Univ, BR-05508900 Sao Paulo - Brazil

^[2] Univ Estadual Santa Cruz, Rodovia Jorge Amado Km 16, BR-45662000 Ilheus, BA - Brazil

^[3] Univ Padua, Dipartimento Fis & Astron Galileo Galilei, Vicolo Osservatorio 3, I-35122 Padua - Italy

^[4] Osserv Astron Padova, Ist Nazl Astrofis, Vicolo Osservatorio 5, I-35122 Padua - Italy

^[5] Aix Marseille Univ, CNRS, CNES, LAM, Marseille - France

^[6] Univ Fed Rio de Janeiro, Ave Athos da Silveira Ramos, 149 Cidade Univ, BR-21941909 Rio De Janeiro - Brazil

^[7] Univ Fed Rio Grande do Sul, Dept Astron, CP 15051, BR-91501970 Porto Alegre, RS - Brazil

^[8] Ist Nazl Fis Nucl, Sez Pisa, Largo Pontecorvo 3, I-56127 Pisa - Italy

^[9] Astron Observ Abruzzo, INAF, Via M Maggini Sn, I-64100 Teramo - Italy

^[10] Osserv Astron Roma, INAF, Via Frascati 33, I-00040 Rome - Italy

^[11] Space Telescope Sci Inst, 3700 San Martin Dr, Baltimore, MD 21218 - USA

^[12] Inst Astrofis Canarias, E-38200 San Cristobal la Laguna, Canary Islands - Spain

^[13] Univ La Laguna, Dept Astrophys, E-38200 Tenerife, Canary Islands - Spain

^[14] Univ Washington, Dept Astron, Box 351580, Seattle, WA 98195 - USA

^[15] Florida Atlantic Univ, Charles E Schmidt Coll Sci, 777 Glades Rd, Boca Raton, FL 33431 - USA

^[16] Johns Hopkins Univ, Dept Phys & Astron, Ctr Astrophys Sci, Baltimore, MD 21218 - USA

^[17] Indiana Univ, Dept Astron, Bloomington, IN 47401 - USA

• Tipo de documento: Artigo Científico
• Fonte: ASTROPHYSICAL JOURNAL; v. 891, n. 1 MAR 1 2020.
• Citações Web of Science: 0

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
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 18/22044-3 - Aglomerados globulares do bojo: relíquias da formação e evolução da galáxia
• Beneficiário: Stefano Oliveira de Souza
• Linha de fomento: Bolsas no Brasil - Doutorado Direto
• Processo FAPESP: 18/22181-0 - Gradientes de idade e metalicidade dos aglomerados estelares da Ponte de Magalhães
• Beneficiário: Raphael Augusto Pereira de Oliveira
• Linha de fomento: Bolsas no Brasil - Doutorado