125 research outputs found
On the early evolution of the Galactic Halo
It is shown that the low metallicity tail of the stellar metallicity
distribution predicted by simple Outflow models for the Milky Way halo depends
sensitively on whether Instantaneous Recycling is adopted or relaxed. In both
cases, current - and still preliminary - data suggest a ``G-dwarf problem'' for
the halo (reminiscent of the local disk). We suggest that the problem can be
solved by introducing a (physically motivated) early infall phase. We point out
several important implications of such a modification, concerning: the putative
Pop. III (super)massive stars, the number of stars expected at very low
metallicities, the questions of primary nitrogen and of the dispersion in
abundance ratios of halo stars.Comment: Astronomy and Astrophysics, accepted for publication (5 pages, 1
fig.
Hybridization in parasites: consequences for adaptive evolution, pathogenesis and public health in a changing world
[No abstract available
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