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arXiv · 1309.4674

Quasi-elastic scattering in the 20Ne + 90,92Zr reactions: role of non-collective excitations

S. Yusa·K. Hagino·N. Rowley
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Abstract

Conventional coupled-channels analyses, that take account of only the collective excitations of the colliding nuclei, have failed to reproduce the different behavior of the experimental quasi-elastic barrier distributions for the $^{20}$Ne + $^{90,92}$Zr systems. To clarify the origins of this difference, we investigate the effect of non-collective excitations of the Zr isotopes. Describing these excitations in a random-matrix model, we explicitly take them into account in our coupled-channels calculations. The non-collective excitations are capable of reproducing the observed smearing of the peak structure in the barrier distribution for $^{20}$Ne + $^{92}$Zr, while not significantly altering the structure observed in the $^{20}$Ne + $^{90}$Zr system. The difference is essentially related to the closed neutron shell in $^{90}$Zr.

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S. Yusa, K. Hagino, N. Rowley. 2013-09-18. Quasi-elastic scattering in the 20Ne + 90,92Zr reactions: role of non-collective excitations. https://doi.org/10.1103/physrevc.88.054621

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