Branching Fraction for B0 -> pi- l+ nu and Determination of |Vub| in Upsilon(4S) -> B0 B0bar Events Tagged by B0bar -> D(*)+ l- nubar

Conference · Wed Jun 29 04:00:00 EDT 2005

OSTI ID:881141

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

We report preliminary results from a study of the charmless exclusive semileptonic decay B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu} based on the data collected at the {Upsilon}(4S) resonance using the BABAR detector at SLAC. The analysis uses events in which the signal B meson recoils against a B meson that has been reconstructed in a semileptonic decay {bar B}{sup 0} {yields} D{sup (*)+}{ell}{sup -}{bar {nu}}. We extract the total branching fraction {Beta}(B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}) = (1.03 {+-} 0.25{sub stat.} {+-} 0.13{sub syst.}) x 10{sup -4} and the partial branching fractions in three bins of q{sup 2}, the invariant mass squared of the lepton-neutrino system. From the partial branching fractions and theoretical predictions for the form factors, we determine the magnitude of the CKM matrix element |V{sub ub}|. We find |V{sub ub}| = (3.3 {+-} 0.4{sub stat.} {+-} 0.2{sub syst.} {sub -0.4}{sup +0.8}FF) x 10{sup -3}, where the last error is due to normalization of the form factor.

• Research Organization: Stanford Linear Accelerator Center (SLAC)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 881141
• Report Number(s): SLAC-PUB-11314; hep-ex/0506064
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
B MESONS
Experiment-HEP
HEPEX
FORM FACTORS
MATRIX ELEMENTS
RESONANCE
SEMILEPTONIC DECAY
STANFORD LINEAR ACCELERATOR CENTER