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Toy Model for Pion Production II: The role of three-particle singularities

A. Motzke·Ch. Elster·C. Hanhart
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Abstract

The influence of three-particle breakup singularities on s-wave meson production in nucleon-nucleon collisions is studied within the distorted wave Born approximation. This study is based on a simple scalar model for the two-nucleon interaction and the production mechanism. An algorithm for the exact numerical treatment of the inherent three-body cuts, together with its straightforward implementation is presented. It is also shown that two often-used approximations to avoid the calculation of the three-body breakup are not justified. The possible impact on pion production observables is discussed.

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A. Motzke, Ch. Elster, C. Hanhart. 2002-07-16. Toy Model for Pion Production II: The role of three-particle singularities. https://doi.org/10.1103/physrevc.66.054002

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