Issue |
A&A
Volume 568, August 2014
|
|
---|---|---|
Article Number | L4 | |
Number of page(s) | 4 | |
Section | Letters | |
DOI | https://doi.org/10.1051/0004-6361/201424200 | |
Published online | 14 August 2014 |
Galactic globular cluster 47 Tucanae: new ties between the chemical and dynamical evolution of globular clusters?
1
Institute of Theoretical Physics and Astronomy, Vilnius
University,
A. Goštauto 12,
01108
Vilnius,
Lithuania
e-mail:
arunas.kucinskas@tfai.vu.lt
2
GEPI, Observatoire de Paris, CNRS, Université Paris
Diderot, Place Jules
Janssen, 92190
Meudon,
France
Received: 13 May 2014
Accepted: 4 July 2014
Context. It is generally accepted today that Galactic globular clusters (GGCs) consist of at least two generations of stars that are different in their chemical composition and perhaps age. However, knowledge about the kinematical properties of these stellar generations, which may provide important information for constraining evolutionary scenarios of the GGCs, is still limited.
Aims. We study the connections between chemical and kinematical properties of different stellar generations in the Galactic globular cluster 47 Tuc.
Methods. To achieve this goal, we used abundances of Li, O, and Na determined in 101 main sequence turn-off (TO) stars with the aid of 3D hydrodynamical model atmospheres and NLTE abundance analysis methodology. We divided our sample TO stars into three groups according to their position in the [Li/Na] – [Na/O] plane to study their spatial distribution and kinematical properties.
Results. We find that there are statistically significant radial dependencies of lithium and oxygen abundances, A(Li) and A(O), as well as that of [Li/Na] abundance ratio. Our results show that first-generation stars are less centrally concentrated and dynamically hotter than stars belonging to subsequent generations. We also find a significant correlation between the velocity dispersion and O and Na abundance, and between the velocity dispersion and the [Na/O] abundance ratio.
Key words: globular clusters: general / globular clusters: individual: 47 Tuc / stars: Population II / stars: abundances / stars: kinematics and dynamics
© ESO, 2014
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.