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Neutron-neutron correlation in the halo dissociation of light exotic nuclei

M. T. Yamashita·T. Frederico·Lauro Tomio
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Abstract

We present model results for the two-halo-neutron correlation functions, $C_{nn}$, for the dissociation process of light exotic nuclei modelled as two neutrons and a core. A minimum is predicted for $C_{nn}$ as a function of the relative momentum of the two neutrons, $p_{nn}$, due to the coherence of the neutrons in the halo and final state interaction. Studying the systems $^{14}$Be, $^{11}$Li and $^{6}$He within this model, we show that the numerical asymptotic limit, $C_{nn}\to 1$, occurs only for $p_{nn}\gtrsim$ 400 MeV$/c$, while such limit is reached for much lower values of $p_{nn}$ in an independent particle model as the one used in the analysis of recent experimental data. Our model is consistent with data once the experimental correlation function is appropriately normalized.

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M. T. Yamashita, T. Frederico, Lauro Tomio. 2005-06-09. Neutron-neutron correlation in the halo dissociation of light exotic nuclei. https://doi.org/10.1103/physrevc.72.011601

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