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We review recent results of the Beauty Factories BaBar and Belle on CP violation in the quark sector and constraints on the CKM unitarity triangle. We first present the recent measurement, using BaBar and Belle data, of cos(2β) = cos(2ϕ1) in B0 → D(∗)h0 with $D \rightarrow {K^{0}_{S}} \pi ^{+} \pi ^{-}$ decays, using a combined time-dependent Dalitz plot analysis. The BaBar Dalitz plot analysis of the $B^{+} \rightarrow {K^{0}_{S}} \pi ^{+} \pi ^{0}$ decay is also presented, and shows an evidence for direct CP violation in B+ → K∗(892)π0. A recently published BaBar measurement of the |V ub| CKM matrix element allows to contrain one side of the unitarity triangle. These analyses use the data sets of the BaBar and Belle experiments containing 471 × 106 and 772 × 106 $B\overline {B}$ pairs collected at the Υ(4S) resonance at the asymmetric-energy B factories PEP-II at SLAC and KEKB at KEK, respectively.

Physical review / D 89, 072009 (2014). doi:10.1103/PhysRevD.89.072009, We report measurements of branching fractions of $\tau $ lepton decays to final states with a ${K}_{S}^{0}$ meson using a $669\text{}\text{}{\mathrm{fb}}^{-1}$ data sample accumulated with the Belle detector at the KEKB asymmetric-energy ${e}^{+}{e}^{-}$ collider. The inclusive branching fraction is measured to be $\mathcal{B}\left({\tau }^{-}\to {K}_{S}^{0}{X}^{-}{\nu }_{\tau }\right)=\left(9.15±0.01±0.15\right)×1{0}^{-3}$, where ${X}^{-}$ can be anything; the exclusive branching fractions are $\mathcal{B}\left({\tau }^{-}\to {\pi }^{-}{K}_{S}^{0}{\nu }_{\tau }\right)=\left(4.16±0.01±0.08\right)×\phantom{\rule{0ex}{0ex}}1{0}^{-3}$, $\mathcal{B}\left({\tau }^{-}\to {K}^{-}{K}_{S}^{0}{\nu }_{\tau }\right)=\left(7.40±0.07±0.27\right)×1{0}^{-4}$, $\mathcal{B}\left({\tau }^{-}\to {\pi }^{-}{K}_{S}^{0}{\pi }^{0}{\nu }_{\tau }\right)=\left(1.93±0.02±0.07\right)×1{0}^{-3}$, $\mathcal{B}\left({\tau }^{-}\to {K}^{-}{K}_{S}^{0}{\pi }^{0}{\nu }_{\tau }\right)=\left(7.48±0.10±0.37\right)×1{0}^{-4}$, $\mathcal{B}\left({\tau }^{-}\to {\pi }^{-}{K}_{S}^{0}{K}_{S}^{0}{\nu }_{\tau }\right)=\left(2.33±0.03±0.09\right)×1{0}^{-4}$, $\mathcal{B}\left({\tau }^{-}\to {\pi }^{-}{K}_{S}^{0}{K}_{S}^{0}{\pi }^{0}{\nu }_{\tau }\right)=\left(2.00±0.22±0.20\right)×1{0}^{-5}$, where the first uncertainty is statistical and the second is systematic. For each mode, the accuracy is improved over that of pre-$B$-factory measurements by a factor ranging from five to ten. In ${\tau }^{-}\to {\pi }^{-}{K}_{S}^{0}{K}_{S}^{0}{\pi }^{0}{\nu }_{\tau }$ decays, clear signals for the intermediate states ${\tau }^{-}\to {\pi }^{-}{f}_{1}\left(1285\right){\nu }_{\tau }$ and ${\tau }^{-}\to {K}^{*-}{K}_{S}^{0}{\pi }^{0}{\nu }_{\tau }$ are observed., Published by American Physical Society, [S.l.]