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On systematic errors due to quenching in epsilon-prime over epsilon

Maarten Golterman·Elisabetta Pallante
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Abstract

Recently, we pointed out that chiral transformation properties of penguin operators change in the transition from unquenched to (partially) quenched QCD. As a consequence, new operators appear in (partially) quenched QCD penguins, introducing ambiguities which should be considered a quenching artifact. Here we discuss more specifically the effects of this phenomenon on the quenched Delta I=1/2 K to pi pi amplitude, and in particular, its potential numerical effect on recent lattice estimates for epsilon-prime over epsilon.

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Maarten Golterman, Elisabetta Pallante. 2002-08-28. On systematic errors due to quenching in epsilon-prime over epsilon. https://doi.org/10.1016/s0920-5632(03)01575-5

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