Speaker
Dr.
Marko Petric
(Jozef Stefan Institute)
Description
We report measurements of the branching fraction (BF) and CP asymmetry ($A_{CP}$) for three rare charmless decays $B^0 \to \pi^0 \pi^0$, $B^0 \to \eta^0 K^{*}(892)^{0}$ and $B^+ \to \bar{K}^{*}(892)^{0} K^{*}(892)^{+}$. Previous measurements of the BF($B^0 \to \pi^0 \pi^0$) are significantly larger than theoretical expectations. The measured BF and $A_{CP}$ in this mode are vital for the determination of the $CP$-violation parameter $\phi_2$ based on isospin relations in $B\to \pi \pi$ decays. The mode $B^0 \to \eta^0 K^{*}(892)^{0}$ is sensitive to a potentially large flavor-singlet contribution. Previous studies provided evidence for its existence at the $4\sigma$ level. The decay $B^+ \to \bar{K}^{*}(892)^{0} K^{*}(892)^{+}$ proceeds via the $b \to d$ loop diagram and is sensitive to potential new physics contributions. All three measurements employ the full $\Upsilon(4S)$ data set of $711{\rm fb}^{-1}$ available at Belle and will be our final results for these modes. Further increases in sensitivity will provided by the upcoming Belle II experiment.
Primary author
Prof.
Youngjoon Kwon
(Yonsei University)
