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arXiv · 1705.06607

Superfluid Gap in Neutron Matter from a Microscopic Effective Interaction

Omar Benhar·Giulia De Rosi
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Abstract

Correlated Basis Function (CBF) perturbation theory and the formalism of cluster expansions have been recently employed to obtain an effective interaction from a nuclear Hamiltonian strongly constrained by phenomenology. We report the results of a study of the superfluid gap in pure neutron matter, associated with the formation of Cooper pairs in the $^1S_0$ channel. The calculations have been carried out using an improved version of the CBF effective interaction, in which three-nucleon forces are taken into account using a microscopic model. Our results show that a non-vanishing superfluid gap develops at densities in the range $2 \times 10^{-4} \lesssim ρ/ρ_0 \lesssim 0.1 $, where $ρ_0 = 2.8 \times 10^{14}$ g cm$^{-3}$ is the equilibrium density of isospin-symmetric nuclear matter, corresponding mainly to the neutron star inner crust.

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Omar Benhar, Giulia De Rosi. 2017-10-20. Superfluid Gap in Neutron Matter from a Microscopic Effective Interaction. https://doi.org/10.1007/s10909-017-1823-x

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