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In-Medium Effective Pion Mass from Heavy-Baryon Chiral Perturbation Theory

Tae-Sun Park·Hong Jung·Dong-Pil Min
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Abstract

Using heavy-baryon chiral perturbation theory, we have calculated all the diagrams up to two-loop order which contribute to the S-wave pion self-energy in symmetric nuclear matter. Some subtleties related to the definition of pion fields are discussed. The in-medium pion mass is turned out to be increased by only (5 - 6) per cents in normal nuclear matter density, without any off-shell ambiguity.

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Tae-Sun Park, Hong Jung, Dong-Pil Min. 2001-04-24. In-Medium Effective Pion Mass from Heavy-Baryon Chiral Perturbation Theory. https://arxiv.org/abs/nucl-th/0101064

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