TY  - JOUR
AU  - BABAR Collaboration (Lees, J. P. et al
AU  - Martinez-Vidal, F.
AU  - Oyanguren, A.
PY  - 2017
DA  - 2017//
TI  - Measurement of the inclusive electron spectrum from B meson decays and determination of vertical bar V-ub vertical bar
T2  - Phys. Rev. D
JO  - Physical Review D
SP  - 072001
EP  - 23pp
VL  - 95
IS  - 7
PB  - Amer Physical Soc
AB  - Based on the full BABAR data sample of 466.5 million B (B) over bar pairs, we present measurements of the electron spectrum from semileptonic B meson decays. We fit the inclusive electron spectrum to distinguish Cabibbo-Kobayashi-Maskawa (CKM) suppressed B -> X(u)ev decays from the CKM-favored B -> X(u)ev decays, and from various other backgrounds, and determine the total semileptonic branching fraction B(B -> X(u)ev) = (10.34 +/- 0.04(stat) +/- 0.26(syst))%, averaged over B-+/- and B-0 mesons. We determine the spectrum and branching fraction for charmless B -> X(u)ev decays and extract the CKM element vertical bar V-ub vertical bar, by relying on four different QCD calculations based on the heavy quark expansion. While experimentally, the electron momentum region above 2.1 GeV/c is favored, because the background is relatively low, the uncertainties for the theoretical predictions are largest in the region near the kinematic endpoint. Detailed studies to assess the impact of these four predictions on the measurements of the electron spectrum, the branching fraction, and the extraction of the CKM matrix element vertical bar V-ub vertical bar are presented, with the lower limit on the electron momentum varied from 0.8 GeV/c to the kinematic endpoint. We determine V-ub vertical bar using each of these different calculations and find, vertical bar V-ub vertical bar = (3.794 +/- 0.107(exp) (+0.292)(-0.219) (SF) (+0.078)(-0.068)theory) x 10(-3) (De Fazio and Neubert), (4.563 +/- 0.126(exp) (+0.230)(+0.162)(-0.208)(-0.163)theory) x 10(-3) (Bosch, Lange, Neubert, and Paz), (3.959 +/- 0.104(exp -0.154)(SF-0.079)(+0.164)(+0.042) theory )x 10(-3) (Gambino, Giordano, Ossola, and Uraltsev), (3.848 +/- 0.108(exp -0.070)(theory)(+0.084)) x 10(-3) (dressed gluon exponentiation), where the stated uncertainties refer to the experimental uncertainties of the partial branching fraction measurement, the shape function parameters, and the theoretical calculations.
SN  - 2470-0010
UR  - http://arxiv.org/abs/1611.05624
UR  - https://doi.org/10.1103/PhysRevD.95.072001
DO  - 10.1103/PhysRevD.95.072001
LA  - English
N1  - WOS:000399390900001
ID  - BABARCollaborationLees_etal2017
ER  -