pi^0-eta Mixing and CP Violation

Abstract

We discuss $\ddot{I}{€}^0$ -$\hat{I}\cdot$ mixing and its implication for $\hat{I}{\mu }^{\prime }/\hat{I}\mu$ to next-to-leading order in the low-energy expansion. The big effect due to $\hat{I}\cdot$-$\hat{I}{\cdot }^{\prime }$ mixing is shown to be largely cancelled by other contributions occurring at the same order in the chiral expansion.

8 pages