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arXiv · 1109.0223

Charge radii and neutron correlations in helium halo nuclei

G. Papadimitriou·A. T. Kruppa·N. Michel·W. Nazarewicz·M. Płoszajczak·J. Rotureau
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Abstract

Within the complex-energy configuration interaction framework, we study correlations of valence neutrons to explain the behavior of charge radii in the neutron halo nuclei $^{6,8}$He. We find that the experimentally observed decrease of the charge radius between $^6$He and $^8$He is caused by a subtle interplay between three effects: dineutron correlations, a spin-orbit contribution to the charge radius, and a core swelling effect. We demonstrate that two-neutron angular correlations in the $2^+_1$ resonance of $^6$He differ markedly from the ground-state correlations in $^{6,8}$He.

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G. Papadimitriou, A. T. Kruppa, N. Michel, W. Nazarewicz, M. Płoszajczak, J. Rotureau. 2011-09-01. Charge radii and neutron correlations in helium halo nuclei. https://doi.org/10.1103/physrevc.84.051304

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