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arXiv · hep-lat/9909041

Matrix Elements without Quark Masses on the Lattice

A. Donini·V. Gimenez·L. Giusti·G. Martinelli
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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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A. Donini, V. Gimenez, L. Giusti, G. Martinelli. 1999-09-07. Matrix Elements without Quark Masses on the Lattice. https://doi.org/10.1016/s0920-5632(00)91634-7

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