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Can one extract the pi-neutron scattering length from pi-deuteron scattering?

A. Nogga·C. Hanhart
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Abstract

We give a prove of evidence that the original power counting by Weinberg can be applied to estimate the contributions of the operators contributing to the pi-deuteron scattering length. As a consequence, pi-deuteron observables can be used to extract neutron amplitudes--in case of pi-deuteron scattering this means that the pi-neutron scattering length can be extracted with high accuracy. This result is at variance with recent claims. We discuss the origin of this difference.

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A. Nogga, C. Hanhart. 2005-11-02. Can one extract the pi-neutron scattering length from pi-deuteron scattering?. https://doi.org/10.1016/j.physletb.2005.12.071

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