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S-wave Pairing of $Λ$ Hyperons in Dense Matter

Shmuel Balberg·Nir Barnea
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Abstract

In this work we calculate the $^1S_0$ gap energies of $Λ$ hyperons in neutron star matter. The calculation is based on a solution of the BCS gap equation for an effective G-matrix parameterization of the $Λ-Λ$ interaction with a nuclear matter background, presented recently by Lanskoy and Yamamoto. We find that a gap energy of a few tenths of MeV is expected for $Λ$ Fermi momenta up to about 1.3 fm$^{-1}$. Implications for neutron star matter are examined, and suggest the existence of a $Λ$ $^1S_0$ superfluid between the threshold baryon density for $Λ$ formation and the baryon density where the $Λ$ fraction reaches $15-20%$.

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Shmuel Balberg, Nir Barnea. 1997-09-08. S-wave Pairing of $Λ$ Hyperons in Dense Matter. https://doi.org/10.1103/physrevc.57.409

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