1 v 2 5 J un 2 00 1 BELLE KEK preprint 2001 - 2 Belle preprint 2001 - 3 Measurement of Inclusive Production of Neutral Pions from Υ ( 4 S ) Decays Belle
نویسندگان
چکیده
Using the Belle detector operating at the KEKB ee storage ring, we have measured the mean multiplicity and the momentum spectrum of neutral pions from the decays of the Υ(4S) resonance. We measure a mean of 4.70± 0.04 ± 0.22 neutral pions per Υ(4S) decay.
منابع مشابه
M ar 2 00 1 BELLE KEK preprint 2001 - 3 Belle preprint 2001 - 2 A Measurement of the Branching Fraction for the Inclusive B → X s γ Decays with Belle The Belle Collaboration
We have measured the branching fraction of the inclusive radiative B meson decay B→Xsγ to be Br(B→Xsγ) = (3.36 ± 0.53(stat) ± 0.42(sys) −0.54(th))× 10. The result is based on a sample of 6.07 × 106 BB̄ events collected at the Υ(4S) resonance with the Belle detector at the KEKB asymmetric e+e− storage ring. PACS: 13.40.Hq, 14.40.Nd, 14.65.Fy
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