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Evidence for partial chiral symmetry restoration from pionic atoms

E. Friedman
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Abstract

Extensive data on strong interaction effects in pionic atoms are analyzed with a density-dependent isovector scattering amplitude suggested recently by Weise to result from a density dependence of the pion decay constant. Most of the so-called `missing s-wave repulsion' is removed when adopting this approach, thus indicating a partial chiral symmetry restoration in dense matter. The resulting potentials describe quite well also elastic scattering of 20 MeV pions on Ca. Further tests with elastic scattering are desirable.

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E. Friedman. 2001-08-01. Evidence for partial chiral symmetry restoration from pionic atoms. https://doi.org/10.1016/s0370-2693(01)01326-0

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