ISSN - 15507998, Physical Review D - Particles, Fields, Gravitation and Cosmology, 2005, vol. 71, p. 031502-1
Improved measurements of the partial rate asymmetry in B → hh decays
We report improved measurements of the partial rate asymmetry (A CP) in B → hh decays with 140 fb -1 of data collected with the Belle detector at the KEKB e +e - collider. Here h stands for a charged or neutral pion or kaon and in total five decay modes are included: K ±π ±, K s 0π ±, K ±π 0, π ±π 0, and K s 0π 0. The flavor of the last decay mode is determined from the accompanying B meson. Using a data sample 4.7 times larger than that of our previous measurement, we find A CP(K ±π ±) - 0.088 ± 0.035 ± 0.013, 2.4σ from zero. Results for other decay modes are also presented. © 2005 The American Physical Society.