1108.3542 (Ruth C. Peterson)
Ruth C. Peterson
We report determinations of the molybdenum abundances in five mildly to
extremely metal-poor turnoff stars using five Mo II lines near 2000A. In two of
the stars, the abundance of molybdenum is found to be extremely enhanced, as
high or higher than the neighboring even-Z elements ruthenium and zirconium. Of
the several nucleosynthesis scenarios envisioned for the production of nuclei
in this mass range in the oldest stars, a high-entropy wind acting in a
core-collapse supernova seems uniquely capable of the twin aspects of a high
molybdenum overproduction confined to a narrow mass range. Whatever the details
of the nucleosynthesis mechanism, however, this unusual excess suggests that
very few individual nucleosynthesis events were responsible for the synthesis
of the light trans-Fe heavy elements in these cases, an unexpected result given
that both are only moderately metal-poor.
View original:
http://arxiv.org/abs/1108.3542
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