Вы находитесь на старом сайте НГУ. Перейти на новый сайт

ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2004, vol. 71, p. 032005-1

Time-integrated and time-dependent angular analyses of B → J/ψKπ: A measurement of cos2β with no sign ambiguity from strong phases

Aubert B., Barate R., Boutigny D., Couderc F., Gaillard J. M., Karyotakis Y., Lees J. P., Poireau V., Tisserand V., Zghiche A., Palano A., Pompili A., Chen J. C., Qi N. D., Rong G., Wang P., Zhu Y. S., Eigen G., Ofte I., Stugu B., Abrams G. S., Borgland A. W., Breon A. B., Brown D. N., Button-Shafer J., Cahn R. N., Charles E., Day C. T., Gill M. S., Gritsan A. V., Groysman Y., Jacobsen R. G., Kadel R. W., Kadyk J., Kerth L. T., Kolomensky Yu G., Kukartsev G., Lynch G., Mir L. M., Oddone P. J., Orimoto T. J., Pripstein M., Roe N. A., Ronan M. T., Shelkov V. G., Wenzel W. A., Barrett M., Ford K. E., Harrison T. J., Hart A. J., Hawkes C. M., Morgan S. E., Watson A. T., Fritsch M., Goetzen K., Held T., Koch H., Lewandowski B., Pelizaeus M., Steinke M., Boyd J. T., Chevalier N., Cottingham W. N., Kelly M. P., Latham T. E., Wilson F. F., Cuhadar-Donszelmann T., Hearty C., Knecht N. S., Mattison T. S., McKenna J. A., Thiessen D., Khan A., Kyberd P., Teodorescu L., Blinov A. E., Blinov V. E., Druzhinin V. P., Golubev V. B., Ivanchenko V. N., Kravchenko E. A., Onuchin A. P., Serednyakov S. I., Skovpen Yu I., Solodov E. P., Yushkov A. N., Best D., Bruinsma M., Chao M., Eschrich I., Kirkby D., Lankford A. J., Mandelkern M., Mommsen R. K., Roethel W., Stoker D. P., Buchanan C., Hartfiel B. L., Foulkes S. D., Gary J. W.

We present results on B → J/ψKπ decays using e<sup>+</sup> e<sup>-</sup> annihilation data collected with the BABAR detector at the Y(4S) resonance. The detector is located at the PEP-II asymmetric-energy storage ring facility at the Stanford Linear Accelerator Center. Using approximately 88 × 10<sup>6</sup> BB̄ pairs, we measure the decay amplitudes for the flavor eigenmodes and observe strong-phase differences indicative of final-state interactions with a significance of 7.6 standard deviations. We use the interference between the Kπ S-wave and P-wave amplitudes in the region of the K*(892) to resolve the ambiguity in the determination of these strong phases. We then perform an ambiguity-free measurement of cos2β using the angular and time-dependent asymmetry in B → J/ψK* <sup>0</sup>(K<inf>S</inf><sup>0</sup>π<sup>0</sup>) decays. With sin2β fixed at its measured value and cos2β treated as an independent parameter, we find cos2β = 2.72<inf>-0.79</inf><sup>+0.50</sup>(stat) ± 0.27(syst), determining the sign of cos2β to be positive at 86% C.L. © 2005 The American Physical Society.