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Fission barriers of neutron-rich and superheavy nuclei calculated with the ETFSI method

A. Mamdouh·J. M. Pearson·M. Rayet·F. Tondeur
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Abstract

Using the ETFSI (extended Thomas-Fermi plus Strutinsky integral) method, we have calculated the fission barriers of nearly 2000 exotic nuclei, including all the neutron-rich nuclei up to A=318 that are expected to be relevant to the r-process, and all the superheavy nuclei in the vicinity of N=184, with Z<=120. Our calculations were performed with the Skyrme force SkSC4, which was determined in the ETFSI-1 mass fit. For proton-deficient nuclei in the region of N=184 we find the barriers to be much higher than previously believed, which suggests that the r-process path might continue to mass numbers well beyond 300. For the superheavy nuclei we typically find barrier heights of 6-7 MeV.

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A. Mamdouh, J. M. Pearson, M. Rayet, F. Tondeur. 2000-10-27. Fission barriers of neutron-rich and superheavy nuclei calculated with the ETFSI method. https://doi.org/10.1016/s0375-9474(00)00358-4

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