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arXiv · 1801.06463

Late formation of silicon carbide in type II supernovae

Nan Liu·Larry R. Nittler·Conel O'M. D. Alexander·Jianhua Wang
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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 (t1/2=330 day) 49V to 49Ti in the inner highly 28Si-rich Si/S zone. The 49V-49Ti chronometer constrains that these supernova SiC dust grains formed at least two 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.

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Nan Liu, Larry R. Nittler, Conel O'M. D. Alexander, Jianhua Wang. 2018-01-19. Late formation of silicon carbide in type II supernovae. https://doi.org/10.1126/sciadv.aao1054

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