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arXiv · 2003.10701

High precision studies of soft dipole mode in two-neutron halo nuclei: $^{6}$He case

L. V. Grigorenko·N. B. Shulgina·M. V. Zhukov
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Abstract

The "soft dipole" E1 strength function is calculated for the transition from the $^{6}$He $0^+$ ground state to the $1^-$ continuum $^{4}$He+$n$+$n$. The calculations were performed within the hyperspherical harmonics formalism. The sensitivity of the results to the $^{6}$He ground state structure and to final state interactions, are analyzed. The large-basis calculations show the reliably converged results for soft dipole strength function and for momentum correlations of the $^{6}\mbox{He} \rightarrow \, ^{4}$He+$n$+$n$ dissociation products. Transition mechanisms are analyzed based on the momentum correlations. The comparison with experimental data is provided.

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L. V. Grigorenko, N. B. Shulgina, M. V. Zhukov. 2020-05-04. High precision studies of soft dipole mode in two-neutron halo nuclei: $^{6}$He case. https://doi.org/10.1103/physrevc.102.014611

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