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arXiv · 1212.5224

Recursion Relations for Tree-level Amplitudes in the SU(N) Non-linear Sigma Model

Karol Kampf·Jiri Novotny·Jaroslav Trnka
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Abstract

It is well-known that the standard BCFW construction cannot be used for on-shell amplitudes in effective field theories due to bad behavior for large shifts. We show how to solve this problem in the case of the SU(N) non-linear sigma model, i.e. non-renormalizable model with infinite number of interaction vertices, using scaling properties of the semi-on-shell currents, and we present new on-shell recursion relations for all on-shell tree-level amplitudes in this theory.

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Karol Kampf, Jiri Novotny, Jaroslav Trnka. 2012-12-20. Recursion Relations for Tree-level Amplitudes in the SU(N) Non-linear Sigma Model. https://doi.org/10.1103/physrevd.87.081701

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