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arXiv · hep-ph/0201236

Constraints on Higher-Order Perturbative Corrections in $b\to u$ Semileptonic Decays from Residual Renormalization-Scale Dependence

M. R. Ahmady·F. A. Chishtie·V. Elias·A. H. Fariborz·D. G. C. McKeon·T. N. Sherry·T. G. Steele
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Abstract

The constraint of a progressive decrease in residual renormalization scale dependence with increasing loop order is developed as a method for obtaining bounds on unknown higher-order perturbative corrections to renormalization-group invariant quantities. This technique is applied to the inclusive semileptonic process $b\to u \barν_\ell\ell^-$ (explicitly known to two-loop order) to obtain bounds on the three- and four-loop perturbative coefficients that are not accessible via the renormalization group. Using the principle of minimal sensitivity, an estimate is obtained for the perturbative contributions to $Γ(b\to u \barν_\ell\ell^-)$ that incorporates theoretical uncertainty from as-yet-undetermined higher order QCD corrections.

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M. R. Ahmady, F. A. Chishtie, V. Elias, A. H. Fariborz, D. G. C. McKeon, T. N. Sherry, T. G. Steele. 2002-03-07. Constraints on Higher-Order Perturbative Corrections in $b\to u$ Semileptonic Decays from Residual Renormalization-Scale Dependence. https://doi.org/10.1088/0954-3899%2F28%2F6%2F101

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