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arXiv · 1005.0727

Sub-barrier fusion of 32S+90,96Zr: semi-classical coupled-channels approach

H. Q. Zhang·C. J. Lin·F. Yang·H. M. Jia·X. X. Xu·F. Jia·Z. D. Wu·S. T. Zhang·Z. H. Liu·A. Richard·C. Beck
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Abstract

The fusion excitation functions have been measured with rather good accuracy for 32S+90Zr and 32S+96Zr near and below the Coulomb barrier. The sub-barrier cross sections for 32S+96Zr are much larger compared with 32S+90Zr. Semi-classical coupled-channels calculations including two-phonon excitations are capable to describe sub-barrier enhancement only for 32S+90Zr. The remaining disagreement for 32S+96Zr comes from the positive Q-value intermediate neutron transfers in this system. The comparison with 40Ca+96Zr suggests that couplings to the positive Q-value neutron transfer channels may play a role in the sub-barrier fusion enhancement. A rather simple model calculation taking neutron transfers into account is proposed to overcome the discrepancies of 32S+96Zr.

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H. Q. Zhang, C. J. Lin, F. Yang, H. M. Jia, X. X. Xu, F. Jia, Z. D. Wu, S. T. Zhang, Z. H. Liu, A. Richard, C. Beck. 2010-05-05. Sub-barrier fusion of 32S+90,96Zr: semi-classical coupled-channels approach. https://arxiv.org/abs/1005.0727

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