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arXiv · hep-lat/0110097

K0-K0bar mixing from the Schroedinger functional and twisted mass QCD

M. Guagnelli·J. Heitger·C. Pena·S. Sint·A. Vladikas
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Abstract

We describe how the Schroedinger functional and twisted mass QCD can be used to compute the kaon B-parameter B_K on the lattice with Wilson fermions. This new approach is expected to reduce the systematic uncertainties on B_K through a better control of its (nonperturbative) renormalisation. Preliminary results for the bare matrix element in a physical volume of (1.5^3 x 4.5) fm^4 are presented. The renormalisation of the matrix element in a Schroedinger functional scheme is also discussed.

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M. Guagnelli, J. Heitger, C. Pena, S. Sint, A. Vladikas. 2001-10-16. K0-K0bar mixing from the Schroedinger functional and twisted mass QCD. https://doi.org/10.1016/s0920-5632(01)01701-7

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