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Kaon B-parameter using Overlap Fermions

Thomas DeGrand
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Abstract

I present first results from an in-progress calculation of B_K in quenched approximation using overlap fermions. My particular implementation of the overlap uses a kernel with nearest and next-nearest neighbor interactions and HYP-blocked gauge connections. Matching to the continuum NDR regularization is done perturbatively. I present preliminary results at beta=5.9 and 6.1 (lattice spacings 0.125 and 0.09 fm) for quark masses, pseudoscalar decay constants, and B-parameter -- B_K(NDR(mu=2 GeV) is 0.66(3-4).

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Thomas DeGrand. 2002-08-26. Kaon B-parameter using Overlap Fermions. https://doi.org/10.1016/s0920-5632(03)01549-4

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