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Dynamical determination of B_K from improved staggered quarks

E. Gamiz·S. Collins·C. T. H. Davies·J. Shigemitsu·M. Wingate
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Abstract

The scaling corrections that affected previous staggered calculations of B_K have been proved to be reduced by using improved actions (HYP, Asqtad) in the quenched approximation. This improved behaviour allows us to perform a reliable dynamical calculation of B_K including quark vacuum polarization effects using the MILC (2+1) flavour dynamical configurations. We report here on the results from such dynamical calculation. We also discuss the renormalization effects with the Asqtad action.

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E. Gamiz, S. Collins, C. T. H. Davies, J. Shigemitsu, M. Wingate. 2005-09-30. Dynamical determination of B_K from improved staggered quarks. https://arxiv.org/abs/hep-lat/0509188

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