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Relativistic short-range correlation effects on the pion dynamics in nuclear matter

L. B. Leinson·A. Perez
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Abstract

Replicated theoretical attempts of relativistic approaches to the pion self-energy in nuclear matter yield unphysical pion spectra. We demonstrate the crucial dependence of the calculated pion spectra on the correct relativistic accounting for the short-range correlation effects on the pion self-energy in the medium. To do this, we simulate the short-range interactions by phenomenological contact terms in the relativistic Lagrangian density, and derive the pion self-energy by carefully taking into account the relativistic kinematics. The obtained spectrum for the pion-like excitations in cold nuclear matter shows physically meaningful branches, in contrast to those obtained before by different authors by the use of simplified relativistic approaches to the short-range correlations.

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L. B. Leinson, A. Perez. 2003-10-03. Relativistic short-range correlation effects on the pion dynamics in nuclear matter. https://arxiv.org/abs/nucl-th/0307025

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