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Narrow Resonances in Effective Field Theory

P. F. Bedaque·H. -W. Hammer·U. van Kolck
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Abstract

We discuss the power counting for effective field theories with narrow resonances near a two-body threshold. Close to threshold, the effective field theory is perturbative and only one combination of coupling constants is fine-tuned. In the vicinity of the resonance, a second, ``kinematic'' fine-tuning requires a nonperturbative resummation. We illustrate our results in the case of nucleon-alpha scattering.

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P. F. Bedaque, H. -W. Hammer, U. van Kolck. 2003-04-02. Narrow Resonances in Effective Field Theory. https://doi.org/10.1016/j.physletb.2003.07.049

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