QCD sum rules for quark-gluon three-body components in the B meson

We discuss the QCD sum rule calculation of the heavy-quark effective theory parameters, $λ_E$ and $λ_H$, which correspond to matrix elements representing quark-gluon three-body components in the $B$-meson wavefunction. We derive the sum rules for $λ_{E,H}$ calculating the new higher-order QCD corrections, i.e., the order $α_s$ radiative corrections to the Wilson coefficients associated with the dimension-5 quark-gluon mixed condensates, and the power corrections due to the dimension-6 vacuum condensates. We find that the new radiative corrections significantly improve the stability of the corresponding Borel sum rules and lead to the reduction of the values of $λ_{E,H}$. We also discuss the renormalization-group improvement for the sum rules and present update on the values of $λ_{E,H}$.

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