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Pairing correlations in nuclei on the neutron-drip line

K. Hagino·H. Sagawa
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Abstract

Paring correlations in weakly bound nuclei on the edge of neutron drip line is studied by using a three-body model. A density-dependent contact interaction is employed to calculate the ground state of halo nuclei $^{6}$He and $^{11}$Li, as well as a skin nucleus $^{24}$O. Dipole excitations in these nuclei are also studied within the same model. We point out that the di-neutron type correlation plays a dominant role in the halo nuclei $^{6}$He and $^{11}$Li having the coupled spin of the two neutrons $S$=0, while the correlation similar to the BCS type is important in $^{24}$O. Contributions of the spin $S$=1 and S=0 configurations are separately discussed in the low energy dipole excitations.

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K. Hagino, H. Sagawa. 2005-08-29. Pairing correlations in nuclei on the neutron-drip line. https://doi.org/10.1103/physrevc.72.044321

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