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arXiv · hep-ph/9302217

Violations of Dashen's Theorem

J. Bijnens
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Abstract

The electromagnetic contribution to the $K^+ - K^0$ mass difference is calculated in the $1/N_c$ approach including the $SU(3)$ breaking contributions due to a non-zero strange quark mass. The short-distance contribution can be unambiguously determined in terms of the known parameters of the next-to-leading order chiral lagrangian. The long distance part is estimated using the $1/N_c$ approach by Bardeen et al. Relatively large corrections are found.

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J. Bijnens. 1993-03-23. Violations of Dashen's Theorem. https://doi.org/10.1016/0370-2693(93)90089-z

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