Observation of the decay $B^0 to eta K^*(892)^0$

We report a search for charmless hadronic decays of neutral $B$ mesons to $eta K^{*}(892)^{0}$. The results are based on a 711fb$^{-1}$ data sample that contains $772times 10^6 Boverline{B}$ pairs, collected at the $Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric energy $e^+e^-$ collider. We observe the decay for the first time with a significance of 5.0 standard deviations and obtain its branching fraction ${cal B}[B^0toeta K^{*}(892)^{0}]=[2.6pm0.7{rm (stat)}pm0.2{rm (syst)}]times 10^{-6}$. We also measure the $CP$ violating asymmetry as ${cal A}_{CP}[B^0toeta K^{*}(892)^{0}]=-0.22pm0.29{rm (stat)}pm0.07{rm syst}$.

Measurement of Time-Dependent $CP$ Violation in $B^0to etaK^0$ Decays

We present a measurement of the time-dependent $CP$ violation parameters in $B^0toetaK^0$ decays. The measurement is based on the full data sample containing $772times 10^6$ $Bbar{B}$ pairs collected at the $Upsilon(4S)$ resonance using the Belle detector at the KEKB asymmetric-energy $e^+e^-$ collider. The measured values of the mixing-induced and direct $CP$ violation parameters are: begin{align} sin 2 phi^{rm eff}_1 &= +0.68pm 0.07 pm 0.03, onumber mathcal{A}_{etaK^0} &= +0.03pm 0.05pm 0.04, onumber end{align} where the first uncertainty is statistical and the second is systematic. The values obtained are the most accurate to date. Furthermore, these results are consistent with our previous measurements and with the world-average value of $sin 2phi_1$ measured in $B^0to J/psi K^0$ decays.}

Studies of penguin dominated B decays

We present measurements on penguin dominated B decays which are sensitive to new physics, such as CP-violation parameters and branching fractions in $b to s qbar{q}$ and $b to d qbar{q}$ gluonic and radiative decays using a large sample of $Bbar{B}$ pairs recorded at the $Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric energy $e^+e^-$ collider.