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arXiv · 1506.07963

A Universal Damping Mechanism of Quantum Vibrations in Deep Sub-Barrier Fusion Reactions

Takatoshi Ichikawa·Kenichi Matsuyanagi
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Abstract

We demonstrate the damping of quantum octupole vibrations near the touching point when two colliding nuclei approach each other in the mass-asymmetric $^{208}$Pb + $^{16}$O system, for which the strong fusion hindrance was clearly observed. We, for the first time, apply the random-phase approximation method to the heavy-mass asymmetric di-nuclear system to calculate the transition strength $B$(E3) as a function of the center-of-mass distance. The obtained $B$(E3) strengths are substantially damped near the touching point, because the single-particle wave functions of the two nuclei strongly mix with each other and a neck is formed. The energy-weighted sums of $B$(E3) are also strongly correlated with the damping factor which is phenomenologically introduced in the standard coupled-channel calculations to reproduce the fusion hindrance. This strongly indicates that the damping of the quantum vibrations universally occurs in the deep sub-barrier fusion reactions.

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Takatoshi Ichikawa, Kenichi Matsuyanagi. 2015-06-26. A Universal Damping Mechanism of Quantum Vibrations in Deep Sub-Barrier Fusion Reactions. https://doi.org/10.1103/physrevc.92.021602

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