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Calculations of fission rates for r-process nucleosynthesis

I. V. Panov·E. Kolbe·B. Pfeiffer·T. Rauscher·K. -L. Kratz·F. -K. Thielemann
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Abstract

Fission plays an important role in the r-process which is responsible not only for the yields of transuranium isotopes, but may have a strong influence on the formation of the majority of heavy nuclei due to fission recycling. We present calculations of beta-delayed and neutron-induced fission rates, taking into account different fission barriers predictions and mass formulae. It is shown that an increase of fission barriers results naturally in a reduction of fission rates, but that nevertheless fission leads to the termination of the r-process. Furthermore, it is discussed that the probability of triple fission could be high for $A>260$ and have an effect on the formation of the abundances of heavy nuclei. Fission after beta-delayed neutron emission is discussed as well as different aspects of the influence of fission upon r-process calculations.

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I. V. Panov, E. Kolbe, B. Pfeiffer, T. Rauscher, K. -L. Kratz, F. -K. Thielemann. 2004-12-29. Calculations of fission rates for r-process nucleosynthesis. https://doi.org/10.1016/j.nuclphysa.2004.09.115

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