Scalar-isoscalar mesons in pion production at threshold
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.
nucl-th↗