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Chiral condensates and size of the sigma term

G. X. Peng
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Abstract

The in-medium chiral condensate is studied with a new approach which has the advantage of no need for extra assumptions on the current mass derivatives of model parameters. It is shown that the pion-nucleon sigma term is 9/2 times the average current mass of light quarks, if quark confinement is linear. Considering both perturbative and non-perturbative interactions, the chiral condensate decreases monotonously with increasing densities, approaching to zero at about 4 fm^{-3}.

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G. X. Peng. 2004-12-28. Chiral condensates and size of the sigma term. https://doi.org/10.1016/j.nuclphysa.2004.09.058

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