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arXiv · hep-ph/9708327

Hadronic Spectral Moments in Semileptonic B Decays With a Lepton Energy Cut

Adam F. Falk·Michael Luke
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Abstract

We compute the first two moments of the final hadronic invariant mass in inclusive semileptonic B decay, in the presence of a cut on the charged lepton energy. These moments may be measured directly by experiments at the Upsilon(4S) using the neutrino reconstruction technique, which requires such a cut. Measurement of these moments will place constraints on the nonperturbative parameters \barΛand λ_1, which are relevant for extracting the quark masses m_b and m_c, as well as the CKM angle V_cb. We include terms of order α_s^2β_0 and 1/m_b^3 in the operator product expansion, and use the latter to estimate the theoretical uncertainty in the extraction of \barΛand λ_1.

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Adam F. Falk, Michael Luke. 1997-08-12. Hadronic Spectral Moments in Semileptonic B Decays With a Lepton Energy Cut. https://doi.org/10.1103/physrevd.57.424

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