Sum-Rule Results on Exclusive Decays of Heavy Mesons

Abstract

We review QCD sum rule applications to hadronic matrix elements of exclusive $B$ and $D$ decays. Results are presented for the form factors $f^+$ and $F_0$ of $B \rightarrow \pi$ and $D\rightarrow \pi$ transitions. The predictions are used to compute the width of $D^* \rightarrow D \pi$, and to extract the CKM parameter $V_{ub}$ from the measured $B \rightarrow \pi e \nu$ width. Furthermore, we comment on weak annihilation in $B \rightarrow \rho \gamma$, as well as on the radiative decays $D \rightarrow \rho \gamma$, $D \rightarrow K^* \gamma$, and $B \rightarrow \mu \nu \gamma$.