Niharika Rout

20 February 2022

Abstract: This proceeding reports the first measurement of the observables related to hadronic $B$ decays containing charm mesons using 62.8 fb$^{-1}$ of dataset collected by the Belle II experiment along with the first measurement of the the CKM unitarity triangle angle $\phi_3$ from a combining Belle and Belle II datasets that correspond to integrated luminosities of 711~fb$^{-1}$ and 128~fb$^{-1}$, respectively. The measured value of $\phi_3$ is $\left(78.4 \pm 11.4 \pm 0.5 \pm 1.0 \right)^{\circ}$, where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is from the uncertainties on external measurements of the $D$-decay strong-phase parameters.

Keyword(s): CKM, phi3