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

الأصل · EN

We discuss the QCD sum rule calculation of the heavy-quark effective theory parameters, λₑ and λₕ, which correspond to matrix elements representing quark-gluon three-body components in the B-meson wavefunction. We derive the sum rules for λₑ,ₕ calculating the new higher-order QCD corrections, i.e., the order αₛ 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 λₑ,ₕ. We also discuss the renormalization-group improvement for the sum rules and present update on the values of λₑ,ₕ.