We report an improved measurement of the partial-rate CP asymmetry in B ±→K 0π ± decays. The analysis is based on a data sample of 85×10 6 BB̄ pairs collected at the Y(4S) resonance with the Belle detector at the KEKB e +e - storage ring. We measure A CP(K 0π ±) = 0.07- 0.08 +0.09 +0.03 +0.01, where the first and second errors are statistical and systematic, respectively; the corresponding 90% confidence-level interval is -0.10 <A CP(K 0π ±) <0.22.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)