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arXiv · 0706.4153

Non-perturbative renormalization of static-light four-fermion operators in quenched lattice QCD

Filippo Palombi·Mauro Papinutto·Carlos Pena·Hartmut Wittig
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Abstract

We perform a non-perturbative study of the scale-dependent renormalization factors of a multiplicatively renormalizable basis of $Δ{B}=2$ parity-odd four-fermion operators in quenched lattice QCD. Heavy quarks are treated in the static approximation with various lattice discretizations of the static action. Light quarks are described by non-perturbatively ${\rm O}(a)$ improved Wilson-type fermions. The renormalization group running is computed for a family of Schroedinger functional (SF) schemes through finite volume techniques in the continuum limit. We compute non-perturbatively the relation between the renormalization group invariant operators and their counterparts renormalized in the SF at a low energy scale. Furthermore, we provide non-perturbative estimates for the matching between the lattice regularized theory and all the SF schemes considered.

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Filippo Palombi, Mauro Papinutto, Carlos Pena, Hartmut Wittig. 2007-06-28. Non-perturbative renormalization of static-light four-fermion operators in quenched lattice QCD. https://doi.org/10.1088/1126-6708%2F2007%2F09%2F062

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