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arXiv · hep-ph/9912264

pi^0-eta Mixing and CP Violation

G. Ecker·G. Mueller·H. Neufeld·A. Pich
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Abstract

We discuss $π^0$ -$η$ mixing and its implication for $ε'/ ε$ to next-to-leading order in the low-energy expansion. The big effect due to $η$-$η'$ mixing is shown to be largely cancelled by other contributions occurring at the same order in the chiral expansion.

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G. Ecker, G. Mueller, H. Neufeld, A. Pich. 1999-12-07. pi^0-eta Mixing and CP Violation. https://doi.org/10.1016/s0370-2693(00)00213-6

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