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Title: Measurement of the inclusive electron spectrum in charmless semileptonic B decays near the kinematic end point and determination of V{sub ub}

Abstract

We present a measurement of the inclusive electron spectrum in B{yields}X{sub u}e{nu} decays near the kinematic limit for B{yields}X{sub c}e{nu} transitions, using a sample of 88x10{sup 6} BB 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{yields}X{sub u}e{nu})=(0.572{+-}0.041{sub stat}{+-}0.065{sub syst})x10{sup -3}. Combining this result with shape function parameters extracted from BABAR measurements of moments of the inclusive photon spectrum in B{yields}X{sub s}{gamma} decays and moments of the hadron-mass and lepton-energy spectra in B{yields}X{sub c}l{nu} decays we determine V{sub ub}=(4.44{+-}0.25{sub exp-0.38SF}{sup +0.42}{+-}0.22{sub theory})x10{sup -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.

Authors:
; ; ; ; ; ; ; ;  [1];  [2]; ; ;  [3]; ; ; ; ;  [4]; ;  [5]
  1. Laboratoire de Physique des Particules, F-74941 Annecy-le-Vieux (France)
  2. IFAE, Universitat Autonoma de Barcelona, E-08193 Bellaterra, Barcelona (Spain)
  3. Dipartimento di Fisica and INFN, Universita di Bari, I-70126 Bari (Italy)
  4. Institute of High Energy Physics, Beijing 100039 (China)
  5. Institute of Physics, University of Bergen, N-5007 Bergen (Norway) (and others)
Publication Date:
OSTI Identifier:
20774573
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 1; Other Information: DOI: 10.1103/PhysRevD.73.012006; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; B MESONS; BRANCHING RATIO; CP INVARIANCE; ELECTRON SPECTRA; ELECTRON-POSITRON INTERACTIONS; ELECTRONS; ENERGY SPECTRA; GEV RANGE; MULTIPARTICLE SPECTROMETERS; PARTICLE IDENTIFICATION; PEP STORAGE RINGS; PHOTONS; QUANTUM CHROMODYNAMICS; REST MASS; SEMILEPTONIC DECAY; STANDARD MODEL; UPSILON-10580 MESONS

Citation Formats

Aubert, B., Barate, R., Boutigny, D., Couderc, F., Karyotakis, Y., Lees, J.P., Poireau, V., Tisserand, V., Zghiche, A., Grauges, E., Palano, A., Pappagallo, M., Pompili, A., Chen, J.C., Qi, N.D., Rong, G., Wang, P., Zhu, Y.S., Eigen, G., and Ofte, I. Measurement of the inclusive electron spectrum in charmless semileptonic B decays near the kinematic end point and determination of V{sub ub}. United States: N. p., 2006. Web. doi:10.1103/PhysRevD.73.012006.
Aubert, B., Barate, R., Boutigny, D., Couderc, F., Karyotakis, Y., Lees, J.P., Poireau, V., Tisserand, V., Zghiche, A., Grauges, E., Palano, A., Pappagallo, M., Pompili, A., Chen, J.C., Qi, N.D., Rong, G., Wang, P., Zhu, Y.S., Eigen, G., & Ofte, I. Measurement of the inclusive electron spectrum in charmless semileptonic B decays near the kinematic end point and determination of V{sub ub}. United States. doi:10.1103/PhysRevD.73.012006.
Aubert, B., Barate, R., Boutigny, D., Couderc, F., Karyotakis, Y., Lees, J.P., Poireau, V., Tisserand, V., Zghiche, A., Grauges, E., Palano, A., Pappagallo, M., Pompili, A., Chen, J.C., Qi, N.D., Rong, G., Wang, P., Zhu, Y.S., Eigen, G., and Ofte, I. Sun . "Measurement of the inclusive electron spectrum in charmless semileptonic B decays near the kinematic end point and determination of V{sub ub}". United States. doi:10.1103/PhysRevD.73.012006.
@article{osti_20774573,
title = {Measurement of the inclusive electron spectrum in charmless semileptonic B decays near the kinematic end point and determination of V{sub ub}},
author = {Aubert, B. and Barate, R. and Boutigny, D. and Couderc, F. and Karyotakis, Y. and Lees, J.P. and Poireau, V. and Tisserand, V. and Zghiche, A. and Grauges, E. and Palano, A. and Pappagallo, M. and Pompili, A. and Chen, J.C. and Qi, N.D. and Rong, G. and Wang, P. and Zhu, Y.S. and Eigen, G. and Ofte, I.},
abstractNote = {We present a measurement of the inclusive electron spectrum in B{yields}X{sub u}e{nu} decays near the kinematic limit for B{yields}X{sub c}e{nu} transitions, using a sample of 88x10{sup 6} BB 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{yields}X{sub u}e{nu})=(0.572{+-}0.041{sub stat}{+-}0.065{sub syst})x10{sup -3}. Combining this result with shape function parameters extracted from BABAR measurements of moments of the inclusive photon spectrum in B{yields}X{sub s}{gamma} decays and moments of the hadron-mass and lepton-energy spectra in B{yields}X{sub c}l{nu} decays we determine V{sub ub}=(4.44{+-}0.25{sub exp-0.38SF}{sup +0.42}{+-}0.22{sub theory})x10{sup -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.},
doi = {10.1103/PhysRevD.73.012006},
journal = {Physical Review. D, Particles Fields},
number = 1,
volume = 73,
place = {United States},
year = {Sun Jan 01 00:00:00 EST 2006},
month = {Sun Jan 01 00:00:00 EST 2006}
}
  • The authors study the inclusive electron spectrum of B --> X{sub u}e{nu} decays near the kinematic limit for B --> X{sub c}e{nu} transitions using a sample of 88 million {Upsilon}(4S) decays recorded by the BABAR detector at the PEP II e{sup +}e{sup -} storage rings. For the electron momentum interval of 2.0-2.6GeV/c the partial branching fraction is measured to be {Delta}B(B --> X{sub u}e{nu}) = (0.480 {+-} 0.029(stat) {+-} 0.053(syst) x 10{sup -3}). Combining this result on {Delta}B with measurements of the inclusive photon spectrum in B --> X{sub s}{gamma} transition the authors find |V{sub ub}| = 3.94 {+-} 0.25expmore » {+-} 0.37 f{sub u} {+-} 0.19 theory x 10{sup -3}, where the first error represents the combined statistical and systematic experimental uncertainty of the partial branching fraction measurement, the second refers to the uncertainty of the determination of the fraction f{sub u} of the inclusive electron spectrum that falls within the cuts, and the third error is due to theoretical uncertainties in the QCD corrections, plus the uncertainty in the b-quark mass. All results are preliminary.« less
  • No abstract prepared.
  • We present a measurement of the inclusive electron spectrum in B {yields} X{sub u}e{nu} decays near the kinematic limit for B {yields} X{sub c}e{nu} transitions, using a sample of 88 million B{bar B} 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}{Beta}(B {yields} X{sub u}e{nu}) = (0.572 {+-} 0.041{sub stat} {+-} 0.065{sub syst}) x 10{sup -3}. Combining this result with shape function parameters extracted from BABAR measurements of moments of the inclusive photon spectrum in Bmore » {yields} X{sub s}{gamma} decays and moments of the hadron mass and lepton energy spectra in B {yields} X{sub c}l{nu} decays we determine |V{sub ub}| = 4.44 {+-} 0.25{sub exp{sub -0.38}{sup +0.42}SF} {+-} 0.22{sub theory} x 10{sup -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.« less
  • We present the partial branching fraction for inclusive charmless semileptonic B decays and the corresponding value of the Cabibbo-Kobayashi-Maskawa matrix element |V{sub ub}|, using a multivariate analysis method to access {approx}90% of the B->X{sub u}lnu phase space. This approach dramatically reduces the theoretical uncertainties from the b-quark mass and nonperturbative QCD compared to all previous inclusive measurements. The results are based on a sample of 657x10{sup 6} BB pairs collected with the Belle detector. We find that {Delta}B(B->X{sub u}l{nu};p{sub l}{sup *B}>1.0 GeV/c)=1.963x(1+-0.088{sub stat}+-0.081{sub syst})x10{sup -3}. Corresponding values of |V{sub ub}| are extracted using several theoretical calculations.
  • A preliminary result on the study of the inclusive electron spectrum in B {yields} X{sub u}e{nu} decays above the kinematic limit for the dominant B {yields} X{sub c}e{nu} transitions is presented. This study is performed at the PEP-II asymmetric B Factory, where B meson pairs are produced in the decay of the {Upsilon}(4S) resonance. For the electron momentum range of 2.3-2.6 GeV/c in the {Upsilon}(4S) rest frame, the partial branching ratio is measured to be {Delta}{Beta}(B {yields} X{sub u}e{nu}) = (0.152 {+-} 0.014 {+-} 0.014) {center_dot} 10{sup -3}.