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Updated: Jun 29, 2026
08:14
Atom Probe Tomography Analysis of Exsolved Mineral Phases
Published on: October 25, 2019
S-process krypton of variable isotopic composition in the Murchison meteorite.
1Max-Planck Institut fur Chemie, Mainz, FRG.
Nature
|April 21, 1988
Summary
This study reveals that s-process krypton in meteorites is a mixture from diverse stellar environments, not a single origin. This finding offers new insights into the nucleosynthesis of elements and early solar system conditions.
Area of Science:
- Cosmochemistry
- Nuclear Astrophysics
- Planetary Science
Background:
- Current theories attribute element abundance to slow (s-process) and rapid (r-process) neutron capture.
- Carbonaceous chondrites provide experimental evidence for these nucleosynthesis theories.
Purpose of the Study:
- To precisely determine the isotopic spectrum of s-process krypton (s-Kr).
- To investigate the origin and astrophysical conditions of s-Kr found in meteorites.
Main Methods:
- Analysis of acid-resistant residues from carbonaceous chondrites.
- Isotopic analysis of krypton to determine its s-process component.
Main Results:
- The s-Kr in the Murchison meteorite is a mixture from stellar environments with varying neutron densities.
- The astrophysical conditions for this s-Kr differ from those explaining Solar System s-process abundances.
- s-Kr from different sites retained its identity within the meteorite.
Conclusions:
- Meteoritic s-Kr provides evidence for multiple stellar nucleosynthesis sites.
- The findings challenge existing models for Solar System element origins.
- Preservation of isotopic signatures in meteorites offers insights into early cosmic history.
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