Busca avançada
Ano de início
Entree
(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Nucleosynthetic history of elements in the Galactic disk [X/Fe]-age relations from high-precision spectroscopy

Texto completo
Autor(es):
Spina, L. ; Melendez, J. ; Karakas, A. I. ; Ramirez, I. ; Monroe, T. R. ; Asplund, M. ; Yong, D.
Número total de Autores: 7
Tipo de documento: Artigo Científico
Fonte: Astronomy & Astrophysics; v. 593, SEP 2016.
Citações Web of Science: 28
Resumo

Context. The chemical composition of stars is intimately linked to the formation and evolution of the Galaxy. Aims. We aim to trace the chemical evolution of the Galactic disk through the inspection of the {[}X/Fe]-age relations of 24 species from C to Eu. Methods. Using high-resolution and high signal-to-noise UVES spectra of nine solar twins, we obtained precise estimates of stellar ages and chemical abundances. These determinations have been integrated with additional accurate age and abundance determinations from recent spectroscopic studies of solar twins existing in the literature, comprising superb abundances with 0.01 dex precision. Based on this data set, we outlined the {[}X/Fe]-age relations over a time interval of 10 Gyr. Results. We present the {[}X/Fe] -age relations for 24 elements (C, O, Na, Mg, Al, Si, S, K, Ca, Sc, Ti, V, Cr, Mn, Co, Ni, Cu, Zn, Y, Ba, La, Ce, Nd, and Eu). Each different class of elements showed a distinct evolution with time that relies on the different characteristics, rates, and timescales of the nucleosynthesis sites from which they are produced. The alpha-elements are characterized by a {[}X/Fe] decrease with time. Strikingly, the opposite behavior is observed for Ca. The iron-peak elements show an early {[}X /Fe] increase followed by a decrease towards the youngest stars. The {[}X /Fe] for the n-capture elements decrease with age. We also found that both {[}Mg/Y] and {[}Al/Y] are precise stellar clocks, with {[}Al/Y] showing the steepest dependence on age. Conclusions. Knowledge of the {[}X /Fe]-age relations is a gold mine from which we can achieve a great understanding of the processes that governed the formation and evolution of the Milky Way. Through the reverse engineering of these relations we will be able to put strong constraints on the nature of the stellar formation history, the SNe rates, the stellar yields, and the variety of the SNe progenitors. (AU)

Processo FAPESP: 14/15706-9 - Abundâncias diferenciais em estrelas de tipo solar: implicações sobre a formação de planetas e nucleossíntese estelar
Beneficiário:Lorenzo Spina
Linha de fomento: Bolsas no Brasil - Pós-Doutorado
Processo FAPESP: 12/24392-2 - Espectroscopia de alta precisão: impacto no estudo de planetas, estrelas, a galáxia e cosmologia
Beneficiário:Jorge Luis Melendez Moreno
Linha de fomento: Auxílio à Pesquisa - Temático