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Quenching effects in strong penguin contributions to $ε'/ε$

Jack Laiho
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Abstract

Quenching effects in strong penguin matrix elements are investigated. A lattice determination of $α_q^{NS}$, the constant that appears in the quenched ChPT relevant for the lattice analysis of $K\toππ$ matrix elements, shows that this constant is large. The original RBC analysis of $Q_6$ matrix elements is revisited in light of this result. Also, the numerical effects of choosing the singlet Golterman-Pallante method of quenching $Q_6$ is investigated.

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Jack Laiho. 2004-09-17. Quenching effects in strong penguin contributions to $ε'/ε$. https://doi.org/10.1016/j.nuclphysbps.2004.11.278

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