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arXiv · hep-ph/9909277

Weak Matrix Elements without Quark Masses on the Lattice

L. Giusti
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Abstract

We introduce a new parameterization of four-fermion matrix elements which does not involve quark masses and thus allows a reduction of systematic uncertainties in physical amplitudes. As a result the apparent quadratic dependence of e'/e on m_s is removed. To simplify the matching between lattice and continuum renormalization schemes, we express our results in terms of Renormalization Group Invariant B-parameters which are renormalization-scheme and scale independent. As an application of our proposal, matrix elements of DeltaI=3/2 and SUSY DeltaF=2 (F=S,C,B) four-fermion operators have been computed.

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L. Giusti. 1999-09-07. Weak Matrix Elements without Quark Masses on the Lattice. https://doi.org/10.1016/s0920-5632(00)00579-x

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