Precision measurements of weak interaction parameters at Belle and Belle II
We report on $CP$ violation measurements at Belle and Belle II, focusing on improving the precision of observables sensitive to the Cabbibo-Kobayashi-Maskawa matrix parameters. We present recent measurements of the CKM unitarity angle $ϕ_2 (α)$ using the $B \to π^0 π^0$ and $B^0 \to ρ^+ ρ^-$ decay channels, along with the first combined $ϕ_3 (γ)$ measurement from Belle and Belle II. Additionally, we discuss the latest determinations of the CKM matrix elements $|V_{cb}|$ and $|V_{ub}|$ through exclusive decay modes $B \to D^{(*)} \ell ν_\ell$ and $B \to π\ell ν_\ell$, respectively. These results demonstrate improved precision and remain consistent with Standard Model predictions.
hep-ex↗