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arXiv · 2108.12736

Quark condensate and chiral symmetry restoration in neutron stars

Hao-Miao Jin·Cheng-Jun Xia·Ting-Ting Sun·Guang-Xiong Peng
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Abstract

Based on an equivparticle model, we investigate the in-medium quark condensate in neutron stars. Carrying out a Taylor expansion of the nuclear binding energy to the order of $ρ^3$, we obtain a series of EOSs for neutron star matter, which are confronted with the latest nuclear and astrophysical constraints. The in-medium quark condensate is then extracted from the constrained properties of neutron star matter, which decreases non-linearly with density. However, the chiral symmetry is only partially restored with non-vanishing quark condensates, which may vanish at a density that is out of reach for neutron stars.

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Hao-Miao Jin, Cheng-Jun Xia, Ting-Ting Sun, Guang-Xiong Peng. 2021-08-29. Quark condensate and chiral symmetry restoration in neutron stars. https://doi.org/10.1016/j.physletb.2022.137121

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