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arXiv · 1305.4323

Dineutron formation and breaking in $^8$He

Fumiharu Kobayashi·Yoshiko Kanada-En'yo
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Abstract

We discuss the correlation of the spin-singlet two-neutron pair, the dineutron correlation, in the ground and excited $0^+$ states of $^8$He by using a method to describe the dineutron correlation in neutron-rich nuclei, the dineutron condensate wave function. The shell-model configuration and the dineutron configuration compete with each other in the ground state of $^8$He. We compare the ground state structure of $^8$He with that of $^6$He and suggest that the dineutron correlation is weaker in the ground state of $^8$He than $^6$He. We also suggest the possibility of the dineutron condensation in an excited $0^+$ state of $^8$He. In addition, we investigate the formation mechanism of the dineutron condensation in $^8$He by using a newly developed framework, $α$ and dineutron condensate wave function, and conclude that the attraction from the core is essential for the formation of the dineutron condensation.

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Fumiharu Kobayashi, Yoshiko Kanada-En'yo. 2013-05-19. Dineutron formation and breaking in $^8$He. https://doi.org/10.1103/physrevc.88.034321

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