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Spatial structure of neutron Cooper pair in low density uniform matter

Masayuki Matsuo
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Abstract

We analyze spatial structure of the neutron Cooper pair in superfluid low-density uniform matter by means of BCS calculations employing a bare force and the effective Gogny interaction. It is shown that the Cooper pair exhibits a strong spatial di-neutron correlation in a wide range of neutron density $ρ/ρ_0\approx 10^{-4}-0.5$. This feature is related to the crossover behavior between the pairing of the weak coupling BCS type and the Bose-Einstein condensation of bound neutron pairs. We also show that the zero-range delta interaction can describe the spatial structure of the neutron Cooper pair if the density dependent interaction strength and the cut-off energy are appropriately chosen. Parameterizations of the density-dependent delta interaction satisfying this condition are discussed.

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Masayuki Matsuo. 2006-02-02. Spatial structure of neutron Cooper pair in low density uniform matter. https://doi.org/10.1103/physrevc.73.044309

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