TTP03-12 Estimate of Charming Penguin Contributions in $B \to \pi\pi$ from QCD Light-Cone Sum Rules

Employing the QCD light-cone sum rule approach we calculate the B → pi pi hadronic matrix element of the current-current operator with c quarks in the penguin topology (``charming penguin''). The

      dominant contribution to the sum rule is due to the c-quark loop at short distances and is of O(alpha_s) with respect to the factorizable B -> pi pi amplitude. The effects of soft gluons are suppressed at least
      by O(alpha_s m_b^{-2}). Our result indicates that sizable nonperturbative effects generated by charming penguins at finite m_b are absent. The same is valid for the penguin contractions of the
      current-current operators with light quarks.