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Kaon Weak Matrix Elements with Wilson Fermions

D. Becirevic·Ph. Boucaud·V. Gimenez·C. -J. D. Lin·V. Lubicz·G. Martinelli·M. Papinutto·C. T. Sachrajda
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Abstract

We present results of several numerical studies with Wilson fermions relevant for kaon physics. We compute the B_K parameter by using two different methods and extrapolate to the continuum limit. Our preliminary result is B_K(2 GeV)=0.66(7). Delta I=3/2 K->pi pi matrix elements are obtained by using the next-to-leading order expressions derived in chiral perturbation theory in which the low energy constants are determined by the lattice results computed at unphysical kinematics. From the simulation at beta=6.0 our (preliminary) results read: _{I=2}=0.14(1)(1) GeV^3 and _{I=2}=0.69(6)(6) GeV^3.

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D. Becirevic, Ph. Boucaud, V. Gimenez, C. -J. D. Lin, V. Lubicz, G. Martinelli, M. Papinutto, C. T. Sachrajda. 2002-09-18. Kaon Weak Matrix Elements with Wilson Fermions. https://doi.org/10.1016/s0920-5632(03)01551-2

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