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arXiv · 1805.01188

Localization of pairing correlations in nuclei within relativistic mean field models

R. -D. Lasseri·J. -P. Ebran·E. Khan·N. Sandulescu
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Abstract

We analyze the localization properties of two-body correlations induced by pairing in the framework of relativistic mean field (RMF) models. The spatial properties of two-body correlations are studied for the pairing tensor in coordinate space and for the Cooper pair wave function. The calculations are performed both with Relativistic-Hatree-Bogoliubov (RHB) and RMF+Projected-BCS (PBCS) models and taking as examples the nuclei $^{66}$Ni, $^{124}$Sn and $^{200}$Pb. It is shown that the coherence length have the same pattern as in previous non-relativistic HFB calculations, i.e., it is maximum in the interior of the nucleus and drops to a minimum in the surface region. In the framework of RMF+PBCS we have also analysed, for the particular case of $^{120}$Sn, the dependence of the coherence length on the intensity of the pairing force. This analysis indicates that pairing is reducing the coherence length by about 25-30 $\%$ compared to the RMF limit.

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R. -D. Lasseri, J. -P. Ebran, E. Khan, N. Sandulescu. 2018-05-03. Localization of pairing correlations in nuclei within relativistic mean field models. https://doi.org/10.1103/physrevc.98.014310

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