Isospin violation in low–energy charged pion–kaon scattering
نویسندگان
چکیده
We evaluate the isospin breaking corrections to the scattering amplitude πK → πK 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.
منابع مشابه
Isospin violation in pion–kaon scattering
We consider strong and electromagnetic isospin violation in near–threshold pion–kaon scattering. At tree level, such effects are small for all physical channels. We work out the complete one–loop corrections to the process π−K+ → π0K0. They come out rather small. We also show that the corresponding radiative cross section is highly suppressed at threshold.
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