ISSN - 00319007, EISSN - 10797114, Physical Review Letters, 2004, vol. 93, p. 131801-1
Direct CP violating asymmetry in B0 → K +π- decays
A measurement of the direct CP violating asymmetry in the decay B 0→K+π- is discussed using a data sample of 227×106 υ(4S)→BB̄ decays. It is found that direct CP violation does not involve particle-antiparticle oscillations. The data sample is collected with the BABAR detector at the PEP-II asymmetric-energy e+e- collider at SLAC. The probability of observing an asymmetry is 1.3×10-5, in the absence of direct CP violation, corresponding to 4.2 standard deviations.