Observation of CP Violation in Charm Decays
Observation of CP Violation in Charm Decays
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DOI：
10.1103/physrevlett.122.211803
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发表时间：
2019-05-29
影响因子：
8.6
通讯作者：
Zucchelli, S.
中科院分区：
文献类型：
--
作者：
Aaij, R.;Beteta, C. Abellan;Zucchelli, S.
报道了用LHCb探测器在13TeV质心能量下收集的积分光度为5.9fb(-1)的pp碰撞数据，对D-0->；K-K+和D-0->；pi(-)pi(+)衰变中的电荷宇称(Cp)破坏进行了研究。魅力介子的性质是从D*(2010)(+)->；D-0pi(+)衰变中的介子的电荷或从(B)中的介子在bar-gt；D-0u(-)(Nu)中的电荷中推断出来的。D-0->；K-K+和D-0->；pi(-)pi(+)衰变的CP不对称性之差被测量为：对于pi标记的介子，Delta A(Cp)=[-18.2+/-3.2(STAT)+/-0.9(Syst)]x 10(-4)；对于u标记的D-0介子，Delta A(Cp)=[-9+/-8(Stat)+/-5(Syst)]x10(-4)。将这些结果与LHCb以前的结果相结合，得到Delta A(Cp)=(-15.4+/-2.9)x 10(-4)，其中不确定度包括统计和系统贡献。测量值与零相差超过5个标准差。这是第一次在魅力强子衰变中观察到CP破坏。
A search for charge-parity (CP) violation in D-0 -> K-K+ and D-0 -> pi(-)pi(+) decays is reported, using pp collision data corresponding to an integrated luminosity of 5.9 fb(-1) collected at a center-of-mass energy of 13 TeV with the LHCb detector. The flavor of the charm meson is inferred from the charge of the pion in D* (2010)(+) -> D-0 pi(+) decays or from the charge of the muon in (B) over bar -> D-0 mu(-)(nu) over bar X-mu decays. The difference between the CP asymmetries in D-0 -> K-K+ and D-0 -> pi(-)pi(+) decays is measured to be Delta A(CP) = [-18.2 +/- 3.2(stat) +/- 0.9(syst)] x 10(-4) for pi-tagged and Delta A(CP) = [-9 +/- 8(stat) +/- 5(syst)] x 10(-4) for mu-tagged D-0 mesons. Combining these with previous LHCb results leads to Delta A(CP) = (-15.4 +/- 2.9) x 10(-4), where the uncertainty includes both statistical and systematic contributions. The measured value differs from zero by more than 5 standard deviations. This is the first observation of CP violation in the decay of charm hadrons.