A&A 419, 181-190 (2004)
DOI: 10.1051/0004-6361:20034393
The K-dwarf problem and the time-dependence of gaseous accretion to the Galactic disc
E. Casuso1 and J. E. Beckman1, 21 Instituto de Astrofísica de Canarias, 38200 La Laguna, Tenerife, Spain
2 Consejo Superior de Investigaciones Científicas, Spain
e-mail: jeb@ll.iac.es
(Received 24 September 2003 / Accepted 19 February 2004 )
Abstract
In this article we compare and contrast the predictions of models we have
published previously, with the most recent observational data on the
G-dwarf/K-dwarf metallicity distribution in the local Galaxy, as well as
with up to date plots showing the relation between the Be and B abundances
of local stars and their Fe abundances. We show how the data clearly support
models in which infall to the plane has not declined secularly during the
disc lifetime, and that the best fits are to models in which the accretion
rate has tended to a slow increase. These models, devised to give the best
possible account of the G-dwarf metallicity distribution, turn out to give
an even better account of the K-dwarf distribution. They also do surprisingly
well at predicting the observed plots of Be and B vs. Fe in the disc.
Key words: Galaxy: disk -- ISM: evolution -- Galaxy: evolution -- Galaxy: abundances
Offprint request: E. Casuso, eca@ll.iac.es
© ESO 2004

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