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ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2009, vol. 79, p. -

Measurements of the semileptonic decays B̄→Dν̄ and B̄→D*ν̄ using a global fit to DXν̄ final states

Aubert B., Bona M., Karyotakis Y., Lees J. P., Poireau V., Prencipe E., Prudent X., Tisserand V., Tico J. Garra, Grauges E., Lopez L., Palano A., Pappagallo M., Eigen G., Stugu B., Sun L., Abrams G. S., Battaglia M., Brown D. N., Cahn R. N., Jacobsen R. G., Kerth L. T., Kolomensky Yu G., Lynch G., Osipenkov I. L., Ronan M. T., Tackmann K., Tanabe T., Hawkes C. M., Soni N., Watson A. T., Koch H., Schroeder T., Walker D., Asgeirsson D. J., Fulsom B. G., Hearty C., Mattison T. S., McKenna J. A., Barrett M., Khan A., Blinov V. E., Bukin A. D., Buzykaev A. R., Druzhinin V. P., Golubev V. B., Onuchin A. P., Serednyakov S. I., Skovpen Yu I., Solodov E. P., Todyshev K. Yu, Bondioli M., Curry S., Eschrich I., Kirkby D., Lankford A. J., Lund P., Mandelkern M., Martin E. C., Stoker D. P., Abachi S., Buchanan C., Gary J. W., Liu F., Long O., Shen B. C., Vitug G. M., Yasin Z., Zhang L., Sharma V., Campagnari C., Hong T. M., Kovalskyi D., Mazur M. A., Richman J. D., Beck T. W., Eisner A. M., Flacco C. J., Heusch C. A., Kroseberg J., Lockman W. S., Schalk T., Schumm B. A., Seiden A., Wang L., Wilson M. G., Winstrom L. O., Cheng C. H., Doll D. A., Echenard B., Fang F., Hitlin D. G., Narsky I., Piatenko T., Porter F. C., Andreassen R., Mancinelli G.

Semileptonic B̄ decays to DXν̄ (=e or μ) are selected by reconstructing D0 and D+ combinations from a sample of 230×106 Υ(4S)→BB̄ decays recorded with the BABAR detector at the PEP-II e+e- collider at SLAC. A global fit to these samples in a three-dimensional space of kinematic variables is used to determine the branching fractions B(B-→D0ν̄)=(2.34±0.03±0.13)% and B(B-→D *0ν̄)=(5.40±0.02±0.21)% where the errors are statistical and systematic, respectively. The fit also determines form-factor parameters in a parametrization based on heavy quark effective theory, resulting in ρD2=1.20±0.04±0.07 for B̄→Dν̄ and ρD*2=1.22±0.02±0.07 for B̄→D*ν̄. These values are used to obtain the product of the Cabibbo-Kobayashi-Maskawa matrix element |Vcb| times the form factor at the zero recoil point for both B̄→Dν̄ decays, G(1)|Vcb|=(43.1±0.8±2.3) ×10-3, and for B̄→D*ν̄ decays, F(1)|Vcb|=(35.9±0.2±1.2)×10-3. © 2009 The American Physical Society.