Observation of the DecayB−→Ds(*)+K−ℓ−ν¯ℓ
Observation of the DecayB−→Ds(*)+K−ℓ−ν¯ℓ
We report the observation of the decay $B^{-} \rightarrow D^{(*)+}_{s} K^{-} \ell^{-} \bar{\nu}_{\ell}$ based on $342 \mathrm {\,fb}^{-1}}$ of data collected at the $\Y4S$ resonance with the BABAR detector at the PEP-II $e^{+}e^{-}$ storage rings at SLAC. A simultaneous fit to three $D^{+}_{s}$ decay chains is performed to extract the …