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Non-perturbative scale evolution of four-fermion operators in two-flavour QCD

ALPHA Collaboration·P. Dimopoulos·G. Herdoiza·F. Palombi·C. Pena·S. Sint·A. Vladikas
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Abstract

We apply finite-size recursion techniques based on the Schrodinger functional formalism to determine the renormalization group running of four-fermion operators which appear in the Delta S=2 effective weak Hamiltonian of the Standard Model. Our calculations are done using O(a) improved Wilson fermions with N_f=2 dynamical flavours. Preliminary results are presented for the four-fermion operator which determines the B_K parameter in tmQCD.

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ALPHA Collaboration, P. Dimopoulos, G. Herdoiza, F. Palombi, C. Pena, S. Sint, A. Vladikas. 2006-10-12. Non-perturbative scale evolution of four-fermion operators in two-flavour QCD. https://arxiv.org/abs/hep-lat/0610077

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