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This content will become publicly available on December 8, 2024

Title: Element abundance patterns in stars indicate fission of nuclei heavier than uranium

The heaviest chemical elements are naturally produced by the rapid neutron-capture process (r-process) during neutron star mergers or supernovae. Ther-process production of elements heavier than uranium (transuranic nuclei) is poorly understood and inaccessible to experiments so must be extrapolated by using nucleosynthesis models. We examined element abundances in a sample of stars that are enhanced inr-process elements. The abundances of elements ruthenium, rhodium, palladium, and silver (atomic numbersZ= 44 to 47; mass numbersA= 99 to 110) correlate with those of heavier elements (63 ≤Z≤ 78,A> 150). There is no correlation for neighboring elements (34 ≤Z≤ 42 and 48 ≤Z≤ 62). We interpret this as evidence that fission fragments of transuranic nuclei contribute to the abundances. Our results indicate that neutron-rich nuclei with mass numbers >260 are produced inr-process events.

 
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Award ID(s):
1927130
PAR ID:
10543565
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Publisher / Repository:
Science
Date Published:
Journal Name:
Science
Volume:
382
Issue:
6675
ISSN:
0036-8075
Page Range / eLocation ID:
1177 to 1180
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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