Bibcode
Adibekyan, V.; Delgado-Mena, E.; Figueira, P.; Sousa, S. G.; Santos, N. C.; González Hernández, J. I.; Minchev, I.; Faria, J. P.; Israelian, G.; Harutyunyan, G.; Suárez-Andrés, L.; Hakobyan, A. A.
Referencia bibliográfica
Astronomy and Astrophysics, Volume 592, id.A87, 12 pp.
Fecha de publicación:
8
2016
Revista
Número de citas
27
Número de citas referidas
22
Descripción
Context. During the past decade, several studies reported a correlation
between chemical abundances of stars and condensation temperature (also
known as Tc trend). However, the real astrophysical nature of
this correlation is still debated. Aims: The main goal of this
work is to explore the possible dependence of the Tc trend on
stellar Galactocentric distances, Rmean. Methods: We
used high-quality spectra of about 40 stars observed with the HARPS and
UVES spectrographs to derive precise stellar parameters, chemical
abundances, and stellar ages. A differential line-by-line analysis was
applied to achieve the highest possible precision in the chemical
abundances. Results: We confirm previous results that [X/Fe]
abundance ratios depend on stellar age and that for a given age, some
elements also show a dependence on Rmean. When using the
whole sample of stars, we observe a weak hint that the Tc
trend depends on Rmean. The observed dependence is very
complex and disappears when only stars with similar ages are considered.
Conclusions: To conclude on the possible dependence of the
Tc trend on the formation place of stars, a larger sample of
stars with very similar atmospheric parameters and stellar ages observed
at different Galactocentric distances is needed.
Based on observations collected with the HARPS spectrograph at the 3.6-m
telescope (program ID: 095.D-0717(A)), installed at the La Silla
Observatory, ESO (Chile), with the UVES spectrograph at the 8-m Very
Large Telescope (program ID: 095.D-0717(B)), installed at the Cerro
Paranal Observatory, ESO (Chile). Also based on data obtained from the
ESO Science Archive Facility under request numbers: vadibekyan180760,
vadibekyan180762, vadibekyan180764, vadibekyan180768, vadibekyan180769,
vadibekyan180771, vadibekyan180773, vadibekyan180778, and
vadibekyan180779.Tables with stellar parameters and chemical abundances
are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/592/A87