We report the observation of the decay B- D(s)((*)+) K- ℓ- nu(ℓ) based on 342fb(-1) of data collected at the Upsilon(4S) 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 signal yield from measurements of the squared missing mass in the B meson decay. We observe the decay B- D(s)((*)+) K- ℓ- nu(ℓ) with a significance greater than 5 standard deviations (including systematic uncertainties) and measure its branching fraction to be B(B- D(s)((*)+) K- ℓ- nu(ℓ)) = [6.13(-1.03)(+1.04)(stat)0.43(syst)0.51(B(D(s)))]*10(-4) where the last error reflects the limited knowledge of the D(s) branching fractions.
Observation of the decay B- D(s)((*)+) K- ℓ- nu(ℓ).
ANDREOTTI, Mirco;CALABRESE, Roberto;CECCHI, Annalisa;CIBINETTO, Gianluigi;FIORAVANTI, Elisa;FRANCHINI, Paolo;LUPPI, Eleonora;MUNERATO, Mauro;NEGRINI, Matteo;PETRELLA, Antonio;SANTORO, Valentina;
2011
Abstract
We report the observation of the decay B- D(s)((*)+) K- ℓ- nu(ℓ) based on 342fb(-1) of data collected at the Upsilon(4S) 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 signal yield from measurements of the squared missing mass in the B meson decay. We observe the decay B- D(s)((*)+) K- ℓ- nu(ℓ) with a significance greater than 5 standard deviations (including systematic uncertainties) and measure its branching fraction to be B(B- D(s)((*)+) K- ℓ- nu(ℓ)) = [6.13(-1.03)(+1.04)(stat)0.43(syst)0.51(B(D(s)))]*10(-4) where the last error reflects the limited knowledge of the D(s) branching fractions.I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
