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arXiv · hep-ph/9312325

Finite Mass Corrections to Leptonic Decay Constants in the Heavy Quark Effective Theory

P. Ball
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Abstract

We calculate finite mass corrections to leptonic decay constants in HQET using QCD sum rules. The results are given to two--loop accuracy including renormalization group analysis. The contribution of unknown two--loop anomalous dimension matrix--elements is estimated. We find that the $1/m_Q$ corrections to $f_P$, the decay constant of a pseudoscalar meson, amount $-(23\pm4\pm2)\%$ for the B meson. The first error comes from the sum rule uncertainty, the second one from unknown or not accurately known matrix elements in HQET. We obtain a ratio of vector to pseudoscalar decay constant of $1.00\pm0.07+O(1/m_Q^2)$ for B mesons.

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BibTeXRIS

P. Ball. 1993-12-22. Finite Mass Corrections to Leptonic Decay Constants in the Heavy Quark Effective Theory. https://doi.org/10.1016/0550-3213(94)90518-5

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