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arXiv · 2007.16184

Evidence for the general dominance of proton shells in low-energy fission

K. Mahata·C. Schmitt·Shilpi Gupta·A. Shrivastava·G. Scamps·K. -H. Schmidt
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Abstract

A regular pattern, revealing the leading role of the light-fragment nuclear charge, is found to emerge from a consistent analysis of the experimental information collected recently on low-energy asymmetric fission of neutron-deficient nuclei around lead. The observation is corroborated by a theoretical investigation within a microscopic framework, suggesting the importance of proton configurations driven by quadrupole-octupole correlations. This is in contrast to the earlier theoretical interpretations in terms of dominant neutron shells. The survey of a wider area of the nuclear chart by a semi-empirical approach points to the lack of understanding of the competition between the different underlying macroscopic and microscopic forces in a quantitative manner. Combined with previously identified stabilizing forces, the present finding shows a striking connection between the "old" (actinide) and "new" (pre-actinide) islands of asymmetric fission which could steer the strive for an unified theory of fission.

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K. Mahata, C. Schmitt, Shilpi Gupta, A. Shrivastava, G. Scamps, K. -H. Schmidt. 2020-07-22. Evidence for the general dominance of proton shells in low-energy fission. https://arxiv.org/abs/2007.16184

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