clover-improved Wilson fermions
نویسندگان
چکیده
We report calculations of the parameter BK appearing in the ∆S = 2 neutral kaon mixing matrix element, whose uncertainty limits the power of unitarity triangle constraints for testing the standard model or looking for new physics. We use two flavours of dynamical clover-improved Wilson lattice fermions and look for dependence on the dynamical quark mass at fixed lattice spacing. We see some evidence for dynamical quark effects and in particular BK decreases as the sea quark masses are reduced towards the up/down quark mass.
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