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Nucleon Sigma Term and In-medium Quark Condensate in the Modified Quark-Meson Coupling Model

Xuemin Jin·Manuel Malheiro
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Abstract

We evaluate the nucleon sigma term and in-medium quark condensate in the modified quark-meson coupling model which features a density-dependent bag constant. We obtain a nucleon sigma term consistent with its empirical value, which requires a significant reduction of the bag constant in the nuclear medium similar to those found in the previous works. The resulting in-medium quark condensate at low densities agrees well with the model independent linear order result. At higher densities, the magnitude of the in-medium quark condensate tends to increase, indicating no tendency toward chiral symmetry restoration.

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Xuemin Jin, Manuel Malheiro. 1999-03-02. Nucleon Sigma Term and In-medium Quark Condensate in the Modified Quark-Meson Coupling Model. https://doi.org/10.1142/s021773239900033x

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