Constraints on $Wtb$ anomalous coupling with $B\to X_s\gamma$ and $B_{s}\to\mu^{+}\mu^{-}

Abstract

We calculate the amplitudes of $b\to s$ transition in extension of the Standard Model with $Wtb$ anomalous couplings. We found that i) there exist the Ward identity violating terms in effective vertix of $b\to s\gamma$. The terms, which come from the tensor parts of $Wtb$ anomalies, and can be canceled exactly by introducing corresponding $Wtb\gamma$ interactions, ii) $Br(B_s\to {\mu }^{+}{\mu }^{-})$ provides unique information on $\delta v_L$ which is set to zero in top decay experiments, and stringent bounds on $v_R,g_L$ by $Br(B\to X_s\gamma )$ are obtained.

Comments: 10 pages, 3 figures