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arXiv · 0808.1946

Next to Leading Order Chiral Perturbation theory of $K π\to π$ and $K\toππ$ amplitudes

Changhoan Kim
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Abstract

It is shown that the low energy coefficients of the next-to-leading order (NLO) chiral perturbation theory needed to determine $ΔI=1/2$, $K\toππ$ decay amplitudes can be fixed by calculating $Kπ\toπ$ amplitudes on lattice. Unlike using NLO $K\toππ$ amplitudes proposed by Laiho and Soni, simulating $Kπ\toπ$ transitions on lattice does not require evaluations of s-channel disconnected diagrams which have been an obstacle in practice.

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Changhoan Kim. 2008-08-29. Next to Leading Order Chiral Perturbation theory of $K π\to π$ and $K\toππ$ amplitudes. https://doi.org/10.1103/physrevd.80.014505

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