Evidence for CP Violation in Time-IntegratedD ! h hþ Decay Rates
نویسنده
چکیده
R. Aaij et al.* (LHCb Collaboration) (Received 6 December 2011; published 12 March 2012; publisher error corrected 12 March 2012) A search for time-integrated CP violation in D ! h hþ (h 1⁄4 K, ) decays is presented using 0:62 fb 1 of data collected by LHCb in 2011. The flavor of the charm meson is determined by the charge of the slow pion in the D þ ! D þ and D ! D decay chains. The difference in CP asymmetry between D ! K Kþ and D ! þ, ACP ACPðK KþÞ ACPð þÞ, is measured to be 1⁄2 0:82 0:21ðstatÞ 0:11ðsystÞ %. This differs from the hypothesis of CP conservation by 3.5 standard deviations.
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