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Understanding the origin of the elements has been a decades-long pursuit, with many open questions remaining. Old stars found in the Milky Way and its dwarf satellite galaxies can provide answers because they preserve clean element abundance patterns of the nucleosynthesis processes that operated some 13 billion years ago, enabling reconstruction of the chemical evolution of the elements. This review focuses on the astrophysical signatures of heavy neutron-capture elements made in the s-, i-, and r-processes found in old stars. A highlight is the recently discovered r-process galaxy Reticulum II, which was enriched by a neutron star merger. These results show that old stars in dwarf galaxies provide a novel means to constrain the astrophysical site of the r-process, ushering in much-needed progress on this major outstanding question. This nuclear astrophysics research complements the many experimental and theoretical nuclear physics efforts into heavy-element formation, and also aligns with results on the gravitational-wave signature of neutron star mergers.
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From the slow to the rapid neutron capture process
Abstract This contribution starts with memories about Franz Käppeler, as a human being and a scientist, his impact on neutron capture nucleosynthesis via experiments and astrophysical studies, before extending from his focus (the s-process) to the r-process, discussing its mechanism, related astrophysical sites and examining in a concluding section its role during galactic evolution.
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- Award ID(s):
- 1927130
- PAR ID:
- 10464362
- Date Published:
- Journal Name:
- The European Physical Journal A
- Volume:
- 59
- Issue:
- 1
- ISSN:
- 1434-601X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1140/epja/s10050-023-00921-z
