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New CLEO Results for |V_cb| and |V_ub|

Roy A. Briere
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Abstract

We report recent measurements from CLEO of the first two moments of the photon energy spectrum for b -> s gamma decays and the hadronic recoil mass in B -> X_c l nu. These physical quantities allow one to fix non-perturbative parameters occurring in calculations based on HQET and QCD. Predictions for semileptonic decay rates within this same framework depend in addition on the CKM matrix elements V_qq' governing quark mixing. We can thus extract |V_cb| from the inclusive semileptonic decay rate of B mesons, and |V_ub| from the lepton endpoint spectrum of B -> X_u l nu. Model dependence is reduced except for the assumption of quark-hadron duality. Finally, we update the classic measurement of |V_cb| from B -> D* l nu at zero recoil.

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Roy A. Briere. 2002-02-13. New CLEO Results for |V_cb| and |V_ub|. https://doi.org/10.1063/1.1478833

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