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arXiv · 1704.01240

Reducing Uncertainties in the Production of the Gamma Emitting Nuclei 26Al, 44Ti, and 60Fe in Core Collapse Supernovae by Using Effective Helium Burning Rates

Sam Austin·Christopher West·Alexander Heger
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Abstract

We have used effective reaction rates (ERR) for the helium burning reactions to predict the yield of the gamma-emitting nuclei 26Al, 44Ti, and 60Fe in core col- lapse supernovae. The variations in the predicted yields for values of the reaction rates allowed by the ERR are much smaller than obtained previously, and smaller than other uncertainties. A "filter" for supernova nucleosynthesis yields based on pre-supernova structure was used to estimate the effect of failed supernovae on the initial mass function-averaged yields; this substantially reduced the yields of all these isotopes, but the predicted yield ratio 60Fe/26Al was little affected. The robustness of this ratio is promising for comparison with data, but it is larger than observed in nature; possible causes for this discrepancy are discussed.

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Sam Austin, Christopher West, Alexander Heger. 2017-04-05. Reducing Uncertainties in the Production of the Gamma Emitting Nuclei 26Al, 44Ti, and 60Fe in Core Collapse Supernovae by Using Effective Helium Burning Rates. https://doi.org/10.3847/2041-8213/aa68e7

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