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Isospin violation in low-energy charged pion-kaon scattering

Bastian Kubis·Ulf-G. Meißner
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Abstract

We evaluate the isospin breaking corrections to the scattering amplitude π^- K^+ -> π^- K^+ at threshold in the framework of chiral perturbation theory. This channel is of particular interest for the strong 2S-2P energy level shift in pion-kaon bound states. While a prediction of this level shift is hampered by a large uncertainty in the isoscalar scattering length, we find only a moderate uncertainty of about 3% in the electromagnetic corrections which are relevant for the extraction of the scattering lengths from experiment

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Bastian Kubis, Ulf-G. Meißner. 2001-12-11. Isospin violation in low-energy charged pion-kaon scattering. https://doi.org/10.1016/s0370-2693(02)01192-9

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