Combined Time-Dependent CP Violation Measurements by the B factory experiments BaBar and Belle

<!--HTML--><p>During the 2000s, the BaBar experiment at SLAC in Stanford/USA and the Belle experiment at KEK in Tsukuba/Japan performed a very successful flavor physics program. In particular, BaBar and Belle discovered CP violation in the neutral and charged B meson system. In this talk, we present the results of two measurements from a novel analysis campaign by the former 'friendly competitors'. The novel approach combines the integrated luminosity of about 1.1 inverse attobarn collected by both experiments in single physics analyses.</p> <p>The first combined measurement presented is a time-dependent CP violation measurement of $B^{0} \to D^{(*)}_{CP} h^{0}$ decays, where the light neutral hadron $h^{0}$ is a $\pi^{0}$, $\eta$ or $\omega$ meson, and the neutral $D$ meson is reconstructed in decays to the two-body CP eigenstates $K^{+}K^{-}$, $K_{S}^{0}\pi^{0}$ or $K_{S}^{0}\omega$. A first observation of CP violation governed by mixing-induced CP violation according to $\sin{2\beta}$ is reported. The second combined measurement presented is a time-dependent Dalitz plot analysis of $B \to D^{(*)} h^{0}$ with $D \to K_{S}^{0} \pi^{+} \pi^{-}$ decays. These decays provide an experimentally elegant and powerful approach to access $\cos{2\beta}$ in addition to $\sin{2\beta}$, and can therefore resolve an ambiguity in the determination of the apex of the CKM Unitarity Triangle. The second combined measurement is technically demanding and includes a full Dalitz plot amplitude analysis of $D \to K_{S}^{0} \pi^{+} \pi^{-}$ decays that is performed on a high-statistics charm data set. We report the first evidence for $\cos{2\beta}&gt;0$, an observation of CP violation, and the exclusion of the second solution of the CKM Unitarity Triangle of $\beta = (68.1 \pm 0.7)^\circ$ at a significance of 7.3 standard deviations.</p> <p>During the talk, the speaker will attempt to highlight various unique physics features of the B factory experiments that include diverse interference phenomena, such as variations of Young's double slit experiment, or the Einstein-Podolsky-Rosen correlation that can be exploited in the measurements.</p> <p>&nbsp;</p>