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Title: Nucleosynthetic Analysis of Three-dimensional Core-collapse Supernova Simulations

We study in detail the ejecta conditions and theoretical nucleosynthetic results for 18 three-dimensional core-collapse supernova (CCSN) simulations done by Fornax. Most of the simulations are carried out to at least 3 s after bounce, which allows us to follow their longer-term behaviors. We find that multidimensional effects introduce many complexities into the ejecta conditions. We see a stochastic electron fraction evolution, complex peak temperature distributions and histories, and long-tail distributions of the time spent within nucleosynthetic temperature ranges. These all lead to substantial variation in CCSN nucleosynthetic yields and differences from 1D results. We discuss the production of lighterα-nuclei, radioactive isotopes, heavier elements, and a few isotopes of special interest. Comparing pre-CCSN and CCSN contributions, we find that a significant fraction of elements between roughly Si and Ge are generally produced in CCSNe. We find that44Ti exhibits an extended production timescale as compared to56Ni, which may explain its different distribution and higher than previously predicted abundances in supernova remnants such as Cas A and SN1987A. We also discuss the morphology of the ejected elements. This study highlights the high-level diversity of ejecta conditions and nucleosynthetic results in 3D CCSN simulations and emphasizes the need for additional long-term (∼10 s) 3D simulations to properly address such complexities.

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Author(s) / Creator(s):
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DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Medium: X Size: Article No. 71
["Article No. 71"]
Sponsoring Org:
National Science Foundation
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