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arXiv · 0809.2895

Non-empirical pairing energy density functional. First order in the nuclear plus Coulomb two-body interaction

T. Lesinski·T. Duguet·K. Bennaceur·J. Meyer
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Abstract

We perform systematic calculations of pairing gaps in semi-magic nuclei across the nuclear chart using the Energy Density Functional method and a {\it non-empirical} pairing functional derived, without further approximation, at lowest order in the two-nucleon vacuum interaction, including the Coulomb force. The correlated single-particle motion is accounted for by the SLy4 semi-empirical functional. Rather unexpectedly, both neutron and proton pairing gaps thus generated are systematically close to experimental data. Such a result further suggests that missing effects, i.e. higher partial-waves of the NN interaction, the NNN interaction and the coupling to collective fluctuations, provide an overall contribution that is sub-leading as for generating pairing gaps in nuclei. We find that including the Coulomb interaction is essential as it reduces proton pairing gaps by up to 40%.

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T. Lesinski, T. Duguet, K. Bennaceur, J. Meyer. 2008-09-17. Non-empirical pairing energy density functional. First order in the nuclear plus Coulomb two-body interaction. https://doi.org/10.1140/epja/i2009-10780-y

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