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A phenomenological determination of the pion-nucleon scattering lengths from pionic hydrogen

T. E. O. Ericson·B. Loiseau·S. Wycech
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Abstract

A model independent expression for the electromagnetic corrections to a phenomenological hadronic pion-nucleon scattering length, extracted from pionic hydrogen, is obtained. In a non-relativistic approach and using an extended charge distribution, these corrections are derived up to terms of order (alpha)**2 log(alpha) in the limit of a short-range hadronic interaction. We infer a charged pion-proton scattering length of 0.0870(5) in units of inverse pion mass, which gives for the charged pion-proton-neutron coupling, through the GMO relation, a value of 14.04(17).

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T. E. O. Ericson, B. Loiseau, S. Wycech. 2004-11-17. A phenomenological determination of the pion-nucleon scattering lengths from pionic hydrogen. https://doi.org/10.1142/s0217751x05023128

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