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Pion re-scattering operator in the S-matrix approach

V. Malafaia·J. Adam Jr·M. T. Pena
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Abstract

The pion re-scattering operator for pion production, derived recently in time-ordered perturbation theory, is compared with the one following from the simple S-matrix construction. We show that this construction is equivalent to the on-shell approximation introduced in previous papers. For a realistic NN interaction, the S-matrix approach, and its simplified fixed threshold-kinematics version, work well near threshold.

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V. Malafaia, J. Adam Jr, M. T. Pena. 2004-11-12. Pion re-scattering operator in the S-matrix approach. https://doi.org/10.1103/physrevc.71.034002

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