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Late formation of silicon carbide in type II supernovae.

ABSTRACT: We have found that individual presolar silicon carbide (SiC) dust grains from supernovae show a positive correlation between ⁴⁹Ti and ²⁸Si excesses, which is attributed to the radioactive decay of the short-lived (t_½ = 330 days) ⁴⁹V to ⁴⁹Ti in the inner highly ²⁸Si-rich Si/S zone. The ⁴⁹V-⁴⁹Ti chronometer shows that these supernova SiC dust grains formed at least 2 years after their parent stars exploded. This result supports recent dust condensation calculations that predict a delayed formation of carbonaceous and SiC grains in supernovae. The astronomical observation of continuous buildup of dust in supernovae over several years can, therefore, be interpreted as a growing addition of C-rich dust to the dust reservoir in supernovae.

SUBMITTER: Liu N

PROVIDER: S-EPMC5777395 | biostudies-literature | 2018 Jan

REPOSITORIES: biostudies-literature

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Late formation of silicon carbide in type II supernovae.

Liu Nan N Nittler Larry R LR Alexander Conel M O'D CMO Wang Jianhua J

Science advances 20180117 1

We have found that individual presolar silicon carbide (SiC) dust grains from supernovae show a positive correlation between 49Ti and 28Si excesses, which is attributed to the radioactive decay of the short-lived (t½ = 330 days) 49V to 49Ti in the inner highly 28Si-rich Si/S zone. The 49V-49Ti chronometer shows that these supernova SiC dust grains formed at least 2 years after their parent stars explod ...[more]

PMID: 29376119

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