v 1 1 6 A ug 2 00 1 CLNS 01 / 1751 CLEO 01 - 16 Branching Fraction and Photon Energy Spectrum for b → sγ CLEO
نویسندگان
چکیده
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) × 10 , 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± 0.011 GeV, and 〈E γ〉−〈Eγ〉 2 = 0.0226±0.0066±0.0020 GeV, where the errors are statistical and systematic. From the first moment we obtain (in MS, to order 1/M and β0α 2 s) the HQET parameter Λ̄ = 0.35 ± 0.08 ± 0.10 GeV.
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