RESEARCH
<< back
Abundance ratios & ages of stellar populations in HARPS-GTO sample

E. Delgado Mena, M. Tsantaki, V. Zh. Adibekyan, S. G. Sousa, N. C. Santos, J. I. GonzŠlez HernŠndez, G. Israelian

Abstract
In this work we present chemical abundances of heavy elements (Z>28) for a homogeneous sample of 1059 stars from HARPS planet search program. We also derive ages using parallaxes from Hipparcos and Gaia DR1 to compare the results. We study the [X/Fe] ratios for different populations and compare them with models of Galactic chemical evolution. We find that thick disk stars are chemically disjunt for Zn adn Eu. Moreover, the high-alpha metal-rich population presents an interesting behaviour, with clear overabundances of Cu and Zn and lower abundances of Y and Ba with respect to thin disk stars. Several abundance ratios present a significant correlation with age for chemically separated thin disk stars (regardless of their metallicity) but thick disk stars do not present that behaviour. Moreover, at supersolar metallicities the trends with age tend to be weaker for several elements.

IAU Symposium S330 (Astrometry and Astrophysics in the Gaia sky)
Alejandra Recio-Blanco, Patrick de Laverny, Anthony G. A. Brown, Timo Prusti

Cambridge University Press
Volume 12, Page 156
2018 March

>> ADS>> DOI

Instituto de Astrof√≠sica e Ci√™ncias do Espa√ßo Universidade do Porto Faculdade de Ciências da Universidade de Lisboa
Fundação para a Ciência e a Tecnologia COMPETE 2020 PORTUGAL 2020 União Europeia