标题： 从奇异衰变中$CP$破坏测量的争议中逃脱 显示英文标题

标题： Escaping from controversies in $CP$ violation measurements in charm decays

摘要： 在 $CP$ 对称性的破坏在 $D^0$ 介子衰变中一直备受期待。 在 LHCb、CDF 和 Belle 合作组提供的一系列测量结果之后，于 2012 年 3 月得出了与在置信度为 $0.006\%$ 下没有 $CP$ 破坏一致的综合结果，表明在 $\sim1\%$ 水平上有 $CP$ 破坏。 在轻子衰变中 $CP$ 破坏的潜在较大值已引起了整个粒子物理界的广泛关注，以评估这种有趣且意外结果的含义。 然而，2013年3月更近期的结果组合略微改变了这种情况，表明数据与$CP$守恒假设在$2.1\%$CL下是一致的。我简要回顾了各合作组在提取数量$\Delta A_{CP}$时所使用的方法及相关结果。最后，我讨论了进行额外测量的必要性，并介绍了在寻找$CP$在$D^0$衰变中的违反情况时，时间依赖性分析的潜力，以及这如何用于大幅提高当前对混合相$\phi_{MIX}$的灵敏度。 显示英文摘要

摘要： The breaking of the $CP$ symmetry in $D^0$ meson decays has been awaited for a long time. After a set of measurements provided by the LHCb, CDF, and Belle Collaborations leading in march 2012 to combined results that were consistent with no $CP$ violation at a CL of $0.006\%$ suggesting $CP$ violation at $\sim1\%$ level. Such a potentially large value of $CP$ violation in charm decays has triggered widespread interest from the whole particle physics community to evaluate the implications of such an interesting unexpected results. However, a more recent combination of more up-to-date results in March 2013, has slightly changed the situation, showing that data are consistent with the $CP$ conserving hypothesis at $2.1\%$ CL. I briefly review the method used by the various Collaborations when extracting the quantity $\Delta A_{CP}$ and the relative results. Finally I discuss the need for additional measurements, and present the potential of a time-dependent analysis when looking for $CP$ violation in $D^0$ decays and how this can be used to largely improve the current sensitivity on the mixing phase $\phi_{MIX}$.