We present a measurement of the inclusive electron spectrum in B -> X(u)e nu decays near the kinematic limit for B -> X(c)e nu transitions, using a sample of 88 x 10(6) B (B) over bar pairs recorded by the BABAR detector at the Upsilon(4S) resonance. Partial branching fraction measurements are performed in five overlapping intervals of the electron momentum; for the interval of 2.0-2.6 GeV/c we obtain Delta B(B -> X(u)e nu) = (0.572 +/- 0.041(stat) +/- 0.065(syst)) x 10(-3). Combining this result with shape function parameters extracted from BABAR measurements of moments of the inclusive photon spectrum in B -> X(s)gamma decays and moments of the hadron-mass and lepton-energy spectra in B -> X(c)l nu decays we determine vertical bar V(ub)vertical bar = (4.44 +/- 0.25(exp-0.38SF)(+0.42) +/- 0.22(theory)) x 10(-3). Here the first error represents the combined statistical and systematic experimental uncertainties of the partial branching fraction measurement, the second error refers to the uncertainty of the determination of the shape function parameters, and the third error is due to theoretical uncertainties in the QCD calculations.

Measurement of the inclusive electron spectrum in charmless semileptonic B decays near the kinematic end point and determination of vertical bar V-ub vertical bar

PALANO, Antimo;PAPPAGALLO, MARCO IGNAZIO;POMPILI, ALEXIS
2006

Abstract

We present a measurement of the inclusive electron spectrum in B -> X(u)e nu decays near the kinematic limit for B -> X(c)e nu transitions, using a sample of 88 x 10(6) B (B) over bar pairs recorded by the BABAR detector at the Upsilon(4S) resonance. Partial branching fraction measurements are performed in five overlapping intervals of the electron momentum; for the interval of 2.0-2.6 GeV/c we obtain Delta B(B -> X(u)e nu) = (0.572 +/- 0.041(stat) +/- 0.065(syst)) x 10(-3). Combining this result with shape function parameters extracted from BABAR measurements of moments of the inclusive photon spectrum in B -> X(s)gamma decays and moments of the hadron-mass and lepton-energy spectra in B -> X(c)l nu decays we determine vertical bar V(ub)vertical bar = (4.44 +/- 0.25(exp-0.38SF)(+0.42) +/- 0.22(theory)) x 10(-3). Here the first error represents the combined statistical and systematic experimental uncertainties of the partial branching fraction measurement, the second error refers to the uncertainty of the determination of the shape function parameters, and the third error is due to theoretical uncertainties in the QCD calculations.
File in questo prodotto:
Non ci sono file associati a questo prodotto.

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/11586/59757
 Attenzione

Attenzione! I dati visualizzati non sono stati sottoposti a validazione da parte dell'ateneo

Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 71
  • ???jsp.display-item.citation.isi??? 143
social impact