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ISSN - 00319007, EISSN - 10797114, Physical Review Letters, 2008, vol. 101, p. -

Measurements of B→{π,η,η′}lνl branching fractions and determination of |Vub| with semileptonically tagged B mesons

Aubert B., Bona M., Karyotakis Y., Lees J. P., Poireau V., Prencipe E., Prudent X., Tisserand V., Garra Tico J., 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., Kukartsev 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., Cuhadar-Donszelmann T., Fulsom B. G., Hearty C., Mattison T. S., McKenna J. A., Barrett M., Khan A., Teodorescu L., 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.

We report measurements of branching fractions for the decays B→P/ν/, where P are the pseudoscalar charmless mesons π-, π0, η and η′, based on 348fb-1 of data collected with the BABAR detector, using B0 and B+ mesons found in the recoil of a second B meson decaying as B→D(*)/ν/. Assuming isospin symmetry, we combine pionic branching fractions to obtain B(B0→π-/+ν/)=(1.54±0. 17(stat)±0.09(syst))×10-4; we find 3.2σ evidence of the decay B+→η/+ν/ and measure its branching fraction to be (0.64±0.20(stat)±0.03(syst))×10-4, and determine B(B+→η′/+ν/)<0.47×10-4 to 90% confidence level. Using partial branching fractions for the pionic decays in ranges of the momentum transfer and a variety of form factor calculation, we obtain values of the magnitude of the Cabibbo-Kobayashi-Maskawa matrix element |Vub| in ranging from 3.6×10-3 to 4.1×10-3. © 2008 The American Physical Society.