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Non-perturbative renormalisation of left-left four-fermion operators with Neuberger fermions

P. Dimopoulos·L. Giusti·P. Hernandez·F. Palombi·C. Pena·A. Vladikas·J. Wennekers·H. Wittig
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Abstract

We outline a general strategy for the non-perturbative renormalisation of composite operators in discretisations based on Neuberger fermions, via a matching to results obtained with Wilson-type fermions. As an application, we consider the renormalisation of the four-quark operators entering the Delta S=1 and Delta S=2 effective Hamiltonians. Our results are an essential ingredient for the determination of the low-energy constants governing non-leptonic kaon decays.

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P. Dimopoulos, L. Giusti, P. Hernandez, F. Palombi, C. Pena, A. Vladikas, J. Wennekers, H. Wittig. 2006-07-20. Non-perturbative renormalisation of left-left four-fermion operators with Neuberger fermions. https://doi.org/10.1016/j.physletb.2006.08.009

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