Weak Radiative B Decays

Abstract

We study the (tree-level) weak radiative decays of $B$ mesons. We present a numerical estimate for the inclusive $b\to X_c\gamma (\gamma )$ modes based on the free-quark decay. We then review what is known for the $B\to D^{\star }\gamma$ modes in the framework of heavy quark effective theory and chiral perturbation theory. Finally, we extend these ideas to the double radiative decay modes $B\to D\gamma \gamma$. We find that the $b\to X_c\gamma \gamma$ rate is about an order of magnitude larger than the corresponding $b\to X_s\gamma \gamma$ rate. We also find the branching ratio for the $B\to D\gamma \gamma$ mode with most favorable CKM angles at the few $\times 10^{-8}$ level, comparable to predictions for $B\to K\gamma \gamma$.

typos corrected, references added, to appear in Phys.Rev.D

Cited by in corpus (2)

• The role of $D^{\star \star }$ in $B^{-}\to D_s^{+}{K}^{-}{\pi }^{-}$
• On the Decay Modes $\overline{B_{d,s}^0}\to \gamma D^{\ast 0}$