Speaker
Description
The Belle and Belle II experiment have collected a 1.2 ab$^{-1}$ sample of $e^+e^-\to B\bar{B}$ decays at a centre-of-mass energy corresponding to the $\Upsilon(4S)$ resonance. The SuperKEKB collider is asymmetric, providing a boost to the $B$ mesons in the laboratory frame, so we can perform measurements of time-dependent $C\!P$ violation. Among the new results, we measure $CP$-violating parameters related to the determination of the least well-known angle of the unitarity triangle $\alpha$ using the decay $B^0\to\rho^+\rho^-$. In addition, we present a measurement of $B^0\to K^{0}_{\rm S}\pi^+\pi^-\gamma$, which is sensitive to beyond-the-standard-model physics. In addition, the study of hadronic $B$ decays in these data allow the precise measurement of absolute branching fractions and angular distributions of the decay products. These measurements provide tests of QCD and allow the generation of more realistic simulation samples. We present several measurements including that of the decay $\bar{B}^0\to D^+\pi^-\pi^0$ and $B$ decays to baryons.
