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arXiv · 0706.0258

In-medium Pions and Partial Restoration of Chiral Symmetry: a model-independent analysis

D. Jido·T. Hatsuda·T. Kunihiro
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Abstract

Exploiting operator relations in QCD, we derive a novel and model-independent formula relating the in-medium quark condensate * to the decay constant F*_t and the wave function renormalization constant Z* of the pion in the nuclear medium. Evaluating Z* at low density from the iso-scalar pion-nucleon scattering data, it is concluded that the enhanced repulsion of the s-wave isovector pion-nucleusinteraction observed in the deeply bound pionic atoms implies directly the reduction of the in-medium quark condensate. The knowlege of the in-medium pion mass is not necessary to reach this conclusion.

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D. Jido, T. Hatsuda, T. Kunihiro. 2007-06-02. In-medium Pions and Partial Restoration of Chiral Symmetry: a model-independent analysis. https://doi.org/10.1143/ptps.168.478

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