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Abundance of live 244Pu in deep-sea reservoirs on Earth points to rarity of actinide nucleosynthesis

Date

2015

Authors

Wallner, Anton
Faestermann, T.
Feige, J.
Feldstein, C
Knie, K.
Korschinek, Gunther
Kutschera, W
Ofan, A
Paul, M.
Quinto, F.

Journal Title

Journal ISSN

Volume Title

Publisher

Macmillan Publishers Ltd

Abstract

Half of the heavy elements including all actinides are produced in r-process nucleosynthesis whose sites and history still remain a mystery. If continuously produced, the Interstellar Medium (ISM) is expected to build up a quasi-steady state of abundances of short-lived nuclides (with half-lives ≤100My), including actinides produced in r-process nucleosynthesis. Their existence in today’s ISM would serve as a radioactive clock and would establish that their production was recent. In particular 244Pu, a radioactive actinide nuclide (81My half-life), can place strong constraints on recent r-process frequency and production yield. Here we report on the detection of live interstellar 244Pu, archived in Earth’s deep-sea floor during the last 25My, at abundances lower by about two orders of magnitude than expected from continuous production in the Galaxy. This large discrepancy may signal a rarity of actinide r-process nucleosynthesis sites, compatible with neutron-star mergers or with a small subset of actinide-producing supernovae.

Description

Keywords

Citation

Source

Nature Communications

Type

Journal article

Book Title

Entity type

Access Statement

Open Access

License Rights

DOI

10.1038/ncomms6956

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