Abundance of live 244Pu in deep-sea reservoirs on Earth points to rarity of actinide nucleosynthesis (original) (raw)
ADS
;
- Faestermann, T. ;
- Feige, J. ;
- Feldstein, C. ;
- Knie, K. ;
- Korschinek, G. ;
- Kutschera, W. ;
- Ofan, A. ;
- Paul, M. ;
- Quinto, F. ;
- Rugel, G. ;
- Steier, P.
Abstract
Half of the heavy elements including all actinides are produced in r-process nucleosynthesis, whose sites and history remain a mystery. If continuously produced, the Interstellar Medium is expected to build-up a quasi-steady state of abundances of short-lived nuclides (with half-lives ≤100 My), including actinides produced in r-process nucleosynthesis. Their existence in today’s interstellar medium would serve as a radioactive clock and would establish that their production was recent. In particular 244Pu, a radioactive actinide nuclide (half-life=81 My), can place strong constraints on recent r-process frequency and production yield. Here we report the detection of live interstellar 244Pu, archived in Earth’s deep-sea floor during the last 25 My, at abundances lower than expected from continuous production in the Galaxy by about 2 orders of magnitude. 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.
Publication:
Nature Communications
Pub Date:
January 2015
DOI:
arXiv:
Bibcode:
Keywords:
- Astrophysics - Solar and Stellar Astrophysics
E-Print:
Nature Communications 6:5956, 2015