Measurement of the inclusive charmless semileptonic branching fraction of beauty hadrons and a determination of |V(ub)| at LEP

A measurement of the inclusive charmless semileptonic branching fraction of beauty hadrons, b→X u ℓ ν , has been performed using almost two million hadronic Z decays collected by the L3 experiment at LEP, yielding the result: Br(b→X u ℓ ν )=(3.3±1.0±1.7)×10 −3 . The first uncertainty is statistical and the second is systematic. The modulus of the Cabibbo-Kobayashi-Maskawa matrix element V ub extracted from this measurement is: | V ub |=(6.0 +0.8 −1.0 +1.4 −1.9 ±0.2)×10 −3 , where the uncertainties are statistical, systematic and theoretical, respectively.

electron positron: colliding beams
electron positron: annihilation
Z0: electroproduction
Z0: hadronic decay
bottom: pair production
bottom: semileptonic decay
bottom: branching ratio
final state: (0charm)
CKM matrix matrix
L3

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Figures(0)

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