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Title: Constraining the Rapid Neutron-Capture Process with Meteoritic I-129 and Cm-247
Meteoritic analysis demonstrates that radioactive nuclei heavier than iron were present in the early Solar System. Among them, 129I and 247Cm both have a rapid neutron-capture process (r process) origin and decay on the same timescale (≃ 15.6 Myr). We show that the 129I/247Cm abundance ratio in the early Solar System (438±184) is immune to galactic evolution uncertainties and represents the first direct observational constraint for the properties of the last r-process event that polluted the pre-solar nebula. We investigate the physical conditions of this event using nucleosynthesis calculations and demonstrate that moderately neutron-rich ejecta can produce the observed ratio. We conclude that a dominant contribution by exceedingly neutron-rich ejecta is highly disfavoured.  more » « less
Award ID(s):
1927130
PAR ID:
10194467
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
ArXivorg
ISSN:
2331-8422
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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