We have measured the branching fraction and photon energy spectrum for the radiative penguin process b→sγ. We find B(b→sγ)=(3.21 ±0.43±0.27−0.10+0.18)×10−4, where the errors are statistical, systematic, and from theory corrections. We obtain first and second moments of the photon energy spectrum above 2.0 GeV,(Eγ)=2.346±0.032±0.011GeV, and (Eγ2)−(Eγ)2=0.0226±0.0066±0.0020 GeV2, where the errors are statistical and systematic. From the first moment, we obtain (in the modified minimal subtraction renormalization scheme, to order 1/MB3 and β0αs2) the heavy quark effective theory parameter Λ¯0.35 ±0.08±0.10 GeV.
ASJC Scopus subject areas
- Physics and Astronomy(all)