Direct CP Violating Asymmetry in B0 -> K+pi- Decays

Abstract

We present a measurement of the direct CP violating asymmetry in the decay B0 -> K+pi- using 227 x 10^6 Y(4S) -> BBbar decays collected with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC, we observe a total signal yield of n(K-pi+) + n(K+pi-) = 1606 +- 51 decays and measure the asymmetry [n(K-pi+)-n(K+pi-)]/[n(K-p+-)+n(K+pi-)] = -0.133+-0.030 (stat) +- 0.009 (syst). The probability of observing such an asymmetry in the absence of direct CP violation is 1.3 x 10^-5, corresponding to 4.2 standard deviations.

PRL version

References in corpus (10)

• Big Bang Nucleosynthesis (in "The Review of Particle Properties" 2004)
• The BABAR Detector
• Observation of Direct CP Violation in K_{S,L} to ππDecays
• A new measurement of direct CP violation in two pion decays of the neutral kaon
• Measurement of the CP-Violating Asymmetry Amplitude sin2beta
• Improved Measurement of Mixing-induced CP Violation in the Neutral B Meson System
• Measurements of Branching Fractions and CP-violating Asymmetries in B0->pi+ pi-, K+ pi-, K+ K- Decays
• Measurement of Charge Asymmetries in Charmless Hadronic in B Meson Decays
• Observation of Large CP Violation and Evidence for Direct CP Violation in B0-->pi+pi- Decays
• Limits on the Decay-Rate Difference of Neutral B Mesons and on CP, T, and CPT Violation in B0-B0bar Oscillations

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