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arXiv · hep-ph/0111249

Counting contact terms in $B\to Vγ$ decays

Alexander Khodjamirian·Daniel Wyler
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Abstract

We clarify the origin and cancellation of contact terms in the weak annihilation amplitudes contributing to $B\to V γ$. It is demonstrated that the photon emission from the final-state quarks vanishes in the chiral limit of massless quarks. The contact terms in the QCD light-cone sum rule evaluation of the weak annihilation amplitudes are also discussed.

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Alexander Khodjamirian, Daniel Wyler. 2001-11-20. Counting contact terms in $B\to Vγ$ decays. https://doi.org/10.1142/9789812777478_0014

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