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Nuclear pairing from chiral pion-nucleon dynamics

N. Kaiser·T. Niksic·D. Vretenar
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Abstract

We use a recently improved version of the chiral nucleon-nucleon potential at next-to-next-to-leading order to calculate the $^1S_0$ pairing gap in isospin-symmetric nuclear matter. The pairing potential consists of the long-range one- and two-pion exchange terms and two short-distance NN-contact couplings. We find that the inclusion of the two-pion exchange at next-to-next-to-leading order reduces substantially the cut-off dependence of the $^1S_0$ pairing gap determined by solving a regularised BCS equation. Our results are close to those obtained with the universal low-momentum nucleon-nucleon potential $V_{\rm low-k}$ or the phenomenological Gogny D1S force.

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N. Kaiser, T. Niksic, D. Vretenar. 2004-11-10. Nuclear pairing from chiral pion-nucleon dynamics. https://doi.org/10.1140/epja%2Fi2005-10122-3

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