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Scalar-isoscalar mesons in pion production at threshold

Claudio M. Maekawa·Carlos A. da Rocha
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Abstract

We present the contributions of the non-linear chiral scalar field S to cross sections of $pp\to dπ^{+}, pp\to pnπ^{+}$ and $pp\to ppπ^0$ reactions at threshold. We compare our results with the meson $σ$ contribution from the $σ$-linear model. We show that the chiral scalar field S is almost 5 times bigger than the other contributions, which indicates that the two-pion exchange dynamics embebbed in the S field is the most important term for the pion production at threshold.

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Claudio M. Maekawa, Carlos A. da Rocha. 1999-07-14. Scalar-isoscalar mesons in pion production at threshold. https://arxiv.org/abs/nucl-th/9905052

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