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The Nuclear Sigma Term in the Skyrme Model: Pion-Nucleus Interaction

A. Gammal·T. Frederico
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Abstract

The nuclear sigma term is calculated including the nuclear matrix element of the derivative of the NN interaction with respect to the quark mass, $m_q\frac{\partial V_{NN}}{\partial m_q}$. The NN potential is evaluated in the skyrmion-skyrmion picture within the quantized product ansatz. The contribution of the NN potential to the nuclear sigma term provides repulsion to the pion-nucleus interaction. The strength of the s-wave pion-nucleus optical potential is estimated including such contribution. The results are consistent with the analysis of the experimental data.

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A. Gammal, T. Frederico. 1998-02-27. The Nuclear Sigma Term in the Skyrme Model: Pion-Nucleus Interaction. https://doi.org/10.1103/physrevc.57.2830

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