Renormalization-Mass Scale Dependence in QCD Contributions to Semileptonic $b \to u$ Decay

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

doi:10.1016/s0920-5632(02)01959-x

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Renormalization-Mass Scale Dependence in QCD Contributions to Semileptonic $b \to u$ Decay

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

QCD contributions to the $b \to u \ell^- \barν_\ell$ decay rate, which are known to two-loop order in the $\bar{MS}$ scheme, exhibit sufficient dependence on the renormalization mass $μ$ to compromise phenomenological predictions for inclusive semileptonic $B \to X_u$ processes. Such scale dependence is ameliorated by the renormalization-group (RG) extraction and summation of all leading and RG-accessible subleading logarithms occurring subsequent to two-loop order in the perturbative series. This optimal RG-improvement of the known portion of the perturbative series virtually eliminates $μ$-dependence as a source of theoretical uncertainty in the predicted semileptonic $B \to X_u$ inclusive rate.

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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. 2002-08-30. Renormalization-Mass Scale Dependence in QCD Contributions to Semileptonic $b \to u$ Decay. https://doi.org/10.1016/s0920-5632(02)01959-x

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