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arXiv · hep-ph/9404236

The Reaction $πN \to ππN$ at Threshold

V. Bernard·N. Kaiser·Ulf-G. Meißner
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Abstract

We consider the chiral expansion for the reaction $πN \to ππN$ in heavy baryon chiral perturbation theory. To order $M_π$ we derive novel low--energy theorems that compare favorably with recent determinations of the total cross sections for $π^+ p \to π^+ π^+ n$ and $π^- p \to π^0 π^0 n$.

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V. Bernard, N. Kaiser, Ulf-G. Meißner. 1994-04-08. The Reaction $πN \to ππN$ at Threshold. https://doi.org/10.1016/0370-2693(94)91274-2

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