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Fusion dynamics around the Coulomb barrier

K. Hagino·N. Rowley·T. Ohtsuki·M. Dasgupta·J. O. Newton·D. J. Hinde
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Abstract

We perform exact coupled-channels calculations, taking into account properly the effects of Coulomb coupling and the finite excitation energy of collective excitations in the colliding nuclei, for three Fm formation reactions, $^{37}$Cl + $^{209}$Bi, $^{45}$Sc + $^{197}$Au, and $^{59}$Co + $^{181}$Ta. For the $^{37}$Cl + $^{209}$Bi and $^{45}$Sc + $^{197}$Au reactions, those calculations well reproduce the experimental total fission cross sections, and a part of the extra-push phenomena can be explained in terms of the Coulomb excitations to multi-phonon states. On the other hand, for the heaviest system, the deep-inelastic collisions become much more significant, and the fission cross sections are strongly overestimated. We also discuss the surprisingly large surface diffuseness parameters required to fit recent high-precision fusion data for medium-heavy systems, in connection with the fusion supression observed in massive systems.

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K. Hagino, N. Rowley, T. Ohtsuki, M. Dasgupta, J. O. Newton, D. J. Hinde. 2003-11-04. Fusion dynamics around the Coulomb barrier. https://doi.org/10.1063/1.1737099

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