olar elemental abundances, or solar system elemental abundances refer to the complement of chemical elements in the entire solar system. The sun contains more than 99-percent of the mass in the solar system and therefore the composition of the sun is a good proxy for the composition of the overall solar system. The solar system composition can be taken as the overall composition of the molecular cloud within the interstellar medium from which the solar system formed 4.567 billion years ago. Active research areas in astronomy and cosmochemistry model collapse of a molecular cloud of solar composition into a star with a planetary system, and the physical and chemical fractionation of the elements during planetary formation and differentiation. The solar system composition is the initial composition from which all solar system objects (the sun, terrestrial planets, gas giant planets, planetary satellites and moons, asteroids, Kuiper-belt objects, and comets) were derived. Other dwarf stars (with hydrostatic Hydrogen-burning in their cores) like our Sun (type G2V dwarf star) within the solar neighborhood have compositions similar to our Sun and the solar system composition. In general, differential comparisons of stellar compositions provide insights about stellar evolution as functions of stellar mass and age, and ongoing nucleosynthesis; but also about galactic chemical evolution when elemental compositions of stellar populations across our Milky Way Galaxy is considered. Comparisons to solar composition can reveal element destruction (e.g., Li) in the sun and in other dwarf stars. The comparisons also show element production of e.g., C, N, O, and the heavy elements made by the s-process in low- to intermediate mass stars (3-7 solar masses) after these evolved from their dwarf-star stage into red giant stars (where hydrogen and helium burning can occur in shells around their cores). The solar system abundances are and have been a critical test composition for nucleosynthesis models and models of Galactic chemical evolution, which aim ultimately to track the production of the elements heavier than hydrogen and helium in the generation of stars that came forth after the Big Bang 13.4 billion years ago. Article at: https://oxfordre.com/planetaryscience/view/10.1093/acrefore/9780190647926.001.0001/acrefore-9780190647926-e-145
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Chemical evolution with rotating massive star yields II. A new assessment of the solar s- and r- process components
Abstract The decomposition of the Solar system abundances of heavy isotopes into their s- and r- components plays a key role in our understanding of the corresponding nuclear processes and the physics and evolution of their astrophysical sites. We present a new method for determining the s- and r- components of the Solar system abundances, fully consistent with our current understanding of stellar nucleosynthesis and galactic chemical evolution. The method is based on a study of the evolution of the solar neighborhood with a state-of-the-art 1-zone model, using recent yields of low and intermediate mass stars as well as of massive rotating stars. We compare our results with previous studies and we provide tables with the isotopic and elemental contributions of the s- and r-processes to the Solar system composition.
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- Award ID(s):
- 1927130
- PAR ID:
- 10193271
- Date Published:
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 491
- ISSN:
- 0035-8711
- Page Range / eLocation ID:
- 1832-1850
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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