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Alpha particle production by molecular single-particle effect in reactions of $^{9}$Be just above the Coulomb barrier

A. Diaz-Torres·I. J. Thompson·W. Scheid
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Abstract

The $α$-particle production in the dissociation of $^{9}$Be on $^{209}$Bi and $^{64}$Zn at energies just above the Coulomb barrier is studied within the two-center shell model approach. The dissociation of $^{9}$Be on $^{209}$Bi is caused by a molecular single-particle effect (Landau-Zener mechanism) before the nuclei reach the Coulomb barrier. Molecular single-particle effects do not occur at that stage of the collision for $^{9}$Be+$^{64}$Zn, and this explains the absence of fusion suppression observed for this system. The polarisation of the energy level of the last neutron of $^{9}$Be and, therefore the existence of avoided crossings with that level, depends on the structure of the target.

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A. Diaz-Torres, I. J. Thompson, W. Scheid. 2004-08-12. Alpha particle production by molecular single-particle effect in reactions of $^{9}$Be just above the Coulomb barrier. https://doi.org/10.1016/s0370-2693(02)01676-3

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