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Superfluid Gap in Neutron Matter from a Microscopic Effective Interaction

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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 \(2 \times 10^{-4} \lesssim \rho /\rho _0 \lesssim 0.1\), where \(\rho _0 = 2.8 \times 10^{14}~\mathrm{g~cm}^{-3}\) is the equilibrium density of isospin-symmetric nuclear matter, corresponding mainly to the neutron-star inner crust.

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Acknowledgements

This research was supported by the Italian National Institute for Nuclear Research (INFN) Under Grant MANYBODY.

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Authors and Affiliations

  1. INFN and Dipartimento di Fisica, Università “La Sapienza”, Roma, Rome, Italy

    Omar Benhar

  2. INO-CNR BEC Center and Dipartimento di Fisica, Università di Trento, Trento, Italy

    Giulia De Rosi

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  1. Omar Benhar
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  2. Giulia De Rosi
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Correspondence to Omar Benhar.

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Benhar, O., De Rosi, G. Superfluid Gap in Neutron Matter from a Microscopic Effective Interaction. J Low Temp Phys 189, 250–261 (2017). https://doi.org/10.1007/s10909-017-1823-x

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