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ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2008, vol. 77, p. -

Determination of the form factors for the decay B0→D*-l+νl and of the CKM matrix element |Vcb|

Aubert B., Bona M., Boutigny D., Karyotakis Y., Lees J. P., Poireau V., Prudent X., Tisserand V., Zghiche A., Tico J. Garra, Grauges E., Lopez L., Palano A., Eigen G., Ofte I., Stugu B., Sun L., Abrams G. S., Battaglia M., Brown D. N., Button-Shafer J., Cahn R. N., Groysman Y., Jacobsen R. G., Kadyk J. A., Kerth L. T., Kolomensky Yu G., Kukartsev G., Pegna D. Lopes, Lynch G., Mir L. M., Orimoto T. J., Pripstein M., Roe N. A., Ronan M. T., Tackmann K., Wenzel W. A., Del Amo Sanchez P., Hawkes C. M., Watson A. T., Held T., Koch H., Lewandowski B., Pelizaeus M., Schroeder T., Steinke M., Cottingham W. N., Walker D., Asgeirsson D. J., Cuhadar-Donszelmann T., Fulsom B. G., Hearty C., Knecht N. S., Mattison T. S., McKenna J. A., Khan A., Saleem M., Teodorescu L., Blinov V. E., Bukin A. D., 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., Foulkes S. D., Gary J. W., Liu F., Long O., Shen B. C., Zhang L., Paar H. P., Rahatlou S., Sharma V., Berryhill J. W., Campagnari C., Cunha A., Dahmes B., Hong T. M., Kovalskyi D., Richman J. D., Beck T. W., Eisner A. M., Flacco C. J., Heusch C. A., Kroseberg J., Lockman W. S.

We present a combined measurement of the Cabibbo-Kobayashi-Maskawa matrix element |Vcb| and of the parameters ρ2, R1(1), and R2(1), which fully characterize the form factors for the B0→D*- +ν decay in the framework of heavy-quark effective field theory. The results, based on a selected sample of about 52800 B0→D*- +ν decays, recorded by the BABAR detector, are ρ2=1.157±0.094±0.027, R1(1)=1. 327±0.131±0.043, R2(1)=0.859±0.077±0.021, and F(1)|Vcb|=(34.7±0.4±1.0)×10-3. The first error is the statistical and the second is the systematic uncertainty. Combining these measurements with the previous BABAR measurement of the form factors, which employs a different fit technique on a partial sample of the data, we improve the statistical precision of the result, ρ2=1.191±0.048±0.028, R1(1)=1.429±0.061±0.044, R2(1)=0.827±0.038±0.022, and F(1)|Vcb|=(34.4±0.3±1.1)×10-3. Using lattice calculations for the axial form factor F(1), we extract |Vcb|=(37.4±0. 3±1.2±1.41.2)×10-3, where the third error is due to the uncertainty in F(1). We also present a measurement of the exclusive branching fraction, B=(4.69±0.04±0.34)%. © 2008 The American Physical Society.