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arXiv · 0810.3531

Possibility of s-wave pion condensates in neutron stars revisited

A. Ohnishi·D. Jido·T. Sekihara·K. Tsubakihara
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Abstract

We examine possibilities of pion condensation with zero momentum (s-wave condensation) in neutron stars by using the pion-nucleus optical potential U and the relativistic mean field (RMF) models. We use low-density phenomenological optical potentials parameterized to fit deeply bound pionic atoms or pion-nucleus elastic scatterings. Proton fraction (Y_p) and electron chemical potential (mu_e) in neutron star matter are evaluated in RMF models. We find that the s-wave pion condensation hardly takes place in neutron stars and especially has no chance if hyperons appear in neutron star matter and/or b_1 parameter in U has density dependence.

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A. Ohnishi, D. Jido, T. Sekihara, K. Tsubakihara. 2009-09-05. Possibility of s-wave pion condensates in neutron stars revisited. https://doi.org/10.1103/physrevc.80.038202

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