Measurement of |Vcb| and the Form-Factor Slope for BBar -> Dlnu Decays on the Recoil of Fully Reconstructed B Mesons

Conference · Thu Aug 21 04:00:00 EDT 2008

OSTI ID:937192

Aubert, B

We present a measurement of the CKM matrix element |V{sub cb}| and the form-factor slope {rho}{sup 2} for {bar B} {yields} D{ell}{sup -} {bar {nu}}{sub {ell}} decays based on 417 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector. The semileptonic decays are selected in B{bar B} events in which the hadronic decay of the second B meson is fully reconstructed. From the measured differential decay rate of the signal decay we determine G(1)|V{sub cb}| = (43.0 {+-} 1.9 {+-} 1.4) x 10{sup -3}, {rho}{sup 2} = 1.20 {+-} 0.09 {+-} 0.04, where G(1) is the hadronic form factor at the point of zero recoil. Using a lattice calculation for G(1) we extract |V{sub cb}| = (39.8 {+-} 1.8 {+-} 1.3 {+-} 0.9) x 10{sup -3}, where the stated errors refer to the statistical, systematic, and form factor uncertainties. We also present a measurement of the exclusive branching fractions, {Beta}(B{sup -} {yields} D{sup 0} {ell}{sup -} {bar {nu}}{sub {ell}}) = (2.31 {+-} 0.08 {+-} 0.07)% and {Beta}({bar B}{sup 0} {yields} D{sup +} {ell}{sup -} {bar {nu}}{sub {ell}}) = (2.23 {+-} 0.11 {+-} 0.08)%.

• Research Organization: Stanford Linear Accelerator Center (SLAC)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-76SF00515
• OSTI ID: 937192
• Report Number(s): SLAC-PUB-13334; arXiv:0807.4978
• Country of Publication: United States
• Language: English

Related Subjects

71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
B MESONS
DECAY
Experiment-HEP
HEPEX
FORM FACTORS
HIGH ENERGY PHYSICS
MATRIX ELEMENTS
RESONANCE
SEMILEPTONIC DECAY