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arXiv · 0804.1557

Four Fermion Operator Matching with NRQCD Heavy and AsqTad Light Quarks

Elvira Gamiz·Junko Shigemitsu·Howard Trottier
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Abstract

We present one-loop matching coefficients between continuum and lattice QCD for the heavy-light four-fermion operators relevant for neutral B meson mixing both within and beyond the Standard Model. For the lattice theory we use nonrelativistic QCD (NRQCD) to describe b quarks and improved staggered fermions (AsqTad) for light quarks. The gauge action is the tree-level Symanzik improved gauge action. Matching to full QCD is carried out through order alpha_s, Lambda_{QCD}/M_b, and alpha_s/(aM_b).

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Elvira Gamiz, Junko Shigemitsu, Howard Trottier. 2008-04-09. Four Fermion Operator Matching with NRQCD Heavy and AsqTad Light Quarks. https://doi.org/10.1103/physrevd.77.114505

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