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Neutron captures produce the vast majority of abundances of elements heavier than iron in the Universe. Beyond the classical slow ( s) and rapid ( r) processes, there is observational evidence for neutron-capture processes that operate at neutron densities in between, at different distances from the valley of β stability. Here, we review the main properties of the s process within the general context of neutron-capture processes and the nuclear physics input required to investigate it. We describe massive stars and asymptotic giant branch stars as the s-process astrophysical sites and discuss the related physical uncertainties. We also present current observational evidence for the s process and beyond, which ranges from stellar spectroscopic observations to laboratory analysis of meteorites.
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Exploding stars and the synthesis of heavy elements: Introducing the facility for rare isotope beams
Since its birth roughly 60 years ago, the field of nuclear astrophysics has strived to provide a comprehensive description of element synthesis in the Universe. While some of the astrophysical processes responsible for stellar nucleosynthesis are well understood, others remained elusive for decades. One of the major open questions in the field centered on the production of elements heavier than iron. An important breakthrough happened in 2017 when gravitational wave and electromagnetic observatories around the world and in space detected for the first time the merging of two neutron stars and the subsequent production of heavy elements. The puzzle, however, is far from solved. Interpreting the observations requires understanding the nuclear processes that drive these events. My work focuses on the measurement of critical nuclear properties needed to explain neutron-star mergers and other astrophysical observations. In this article, I discuss recent experiments performed at the National Superconducting Cyclotron Laboratory at Michigan State University, as well as new initiatives and plans to undertake work at the next-generation rare isotope facility, the Facility for Rare Isotope Beams.
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- Award ID(s):
- 1938815
- PAR ID:
- 10556659
- Publisher / Repository:
- AIP Conference Proceedings
- Date Published:
- Page Range / eLocation ID:
- 070011
- 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
- Conference Paper:
- https://doi.org/10.1063/5.0175775
