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Moments of the photon energy spectrum from $B\to X_s γ$ decays measured by Belle

Belle Collaboration
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Abstract

We report preliminary measurements of the first (mean) and second moment (variance) of the inclusive photon energy spectrum in $B\to X_sγ$ decays, for threshold values of the photon energy in the range 1.8--2.3 GeV as measured in the rest frame of the $B$-meson. These results are obtained from the Belle measurement of the spectrum, which used a data set consisting of 152 million $B\bar{B}$ pairs collected by the Belle detector at the KEKB asymmetric-energy electron-positron collider operated on the $Υ(4S)$ resonance.

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Belle Collaboration. 2005-07-31. Moments of the photon energy spectrum from $B\to X_s γ$ decays measured by Belle. https://arxiv.org/abs/hep-ex/0508005

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