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On relativistic approaches to the pion self-energy in nuclear matter

L. B. Leinson·A. Perez
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Abstract

We argue that, in contrast to the non-relativistic approach, a relativistic evaluation of the nucleon--hole and delta-isobar--nucleon hole contributions to the pion self-energy incorporates the s-wave scattering, which requires a more accurate evaluation. Therefore relativistic approach containing only these diagrams does not describe appropriately the pion self-energy in isospin symmetric nuclear matter. We conclude that, a correct relativistic approach to the pion self-energy should involve a more sophisticated calculation in order to satisfy the known experimental results on the near-threshold behaviour of the pion-nucleon (forward) scattering amplitude.

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L. B. Leinson, A. Perez. 2003-11-30. On relativistic approaches to the pion self-energy in nuclear matter. https://doi.org/10.1140/epja%2Fi2003-10225-9

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