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arXiv · hep-ph/0304179

QCD Light-Cone Sum Rule Estimate of Charming Penguin Contributions in B -> pi pi

A. Khodjamirian·Th. Mannel·B. Melic
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Abstract

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.

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A. Khodjamirian, Th. Mannel, B. Melic. 2003-05-07. QCD Light-Cone Sum Rule Estimate of Charming Penguin Contributions in B -> pi pi. https://doi.org/10.1016/j.physletb.2003.08.012

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