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Studying medium effects with the optimized $\bdelta$ expansion

G. Krein·D. P. Menezes·M. Nielsen·M. B. Pinto
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Abstract

The possibility of using the optimized $δ$ expansion for studying medium effects on hadronic properties in quark or nuclear matter is investigated. The $δ$ expansion is employed to study density effects with two commonly used models in hadron and nuclear physics, the Nambu--Jona-Lasinio model for the dynamical chiral symmetry breaking and the Walecka model for the equation of state of nuclear matter. The results obtained with the $δ$ expansion are compared to those obtained with the traditional Hartree-Fock approximation. Perspectives for using the $δ$ expansion in other field theoretic models in hadron and nuclear physics are discussed.

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G. Krein, D. P. Menezes, M. Nielsen, M. B. Pinto. 1995-05-02. Studying medium effects with the optimized $\bdelta$ expansion. https://arxiv.org/abs/hep-ph/9505216

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