IALP   13078
INSTITUTO DE ASTROFISICA LA PLATA
Unidad Ejecutora - UE
artículos
Título:
The white dwarf cooling sequence of 47 Tucanae
Autor/es:
GARCÍA-BERRO, ENRIQUE; TORRES, SANTIAGO; ALTHAUS, LEANDRO G.; MILLER BERTOLAMI, MARCELO M.
Revista:
ASTRONOMY AND ASTROPHYSICS
Editorial:
EDP SCIENCES S A
Referencias:
Lugar: Paris; Año: 2014
ISSN:
0004-6361
Resumen:
Context. 47 Tucanae is one of the most interesting, well-observed, and
theoretically studied globular clusters. This allows us to determine the
reliability of our understanding of white dwarf cooling sequences, to
compare different methods of determining its age, and to assess other
important characteristics, such as its star formation history.
Aims: Here we present a population synthesis study of the cooling
sequence of the globular cluster 47 Tucanae. In particular, we study the
distribution of effective temperatures, the shape of the color-magnitude
diagram, and the corresponding magnitude and color distributions.
Methods: To do this, we used an up-to-date population synthesis code
based on Monte Carlo techniques that incorporates the most recent and
reliable cooling sequences and an accurate modeling of the observational
biases. Results: Our theoretical models and the observed data
agree well. Thus, our study disproves previous claims that there are
still missing physics in the white dwarf cooling models at moderately
high effective temperatures. We also derive the age of the cluster using
the termination of the cooling sequence and obtain a good agreement with
the age determinations made using the main-sequence turn-off. Finally,
the star formation history of the cluster is compatible with that
obtained using main-sequence stars, which predicts two distinct
populations. Conclusions: We conclude that a correct modeling of
the white dwarf population of globular clusters, used in combination
with the number counts of main -sequence stars, provides a unique tool
to model the properties of globular clusters.