Effects of (partial) quenching on penguin contributions to K→ππ

Maarten Golterman, Elisabetta Pallante

Research output: Contribution to journalArticleAcademic

13 Citations (Scopus)
222 Downloads (Pure)


Recently, we pointed out that chiral transformation properties of strong penguin operators change in the transition from unquenched to (partially) quenched QCD. As a consequence, new penguinlike operators appear in the (partially) quenched theory, along with new low-energy constants, which should be interpreted as a quenching artifact. Here, we extend the analysis of the contribution of the new low-energy constants to the K0→π+π- amplitude, at leading order in chiral perturbation theory, and for arbitrary (momentum nonconserving) kinematics. Using these results, we provide a detailed discussion of the intrinsic systematic error due to this (partial) quenching artifact. We also give a simple recipe for the determination of the leading-order low-energy constant parametrizing the new operators in the case of strong LR penguins operators.
Original languageEnglish
Pages (from-to)074503-1-074503-11
JournalPhysical Review D
Issue number7
Publication statusPublished - 2004

Cite this