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arXiv · 2504.00354

Precision measurements of weak interaction parameters at Belle and Belle II

Ansu Johnson
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Abstract

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 $\phi_2 (\alpha)$ using the $B \to \pi^0 \pi^0$ and $B^0 \to \rho^+ \rho^-$ decay channels, along with the first combined $\phi_3 (\gamma)$ 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 $B \to D^{(*)} \ell \nu_\ell$ and $B \to \pi \ell \nu_\ell$, respectively. These results demonstrate improved precision and remain consistent with Standard Model predictions.

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Ansu Johnson. 2025-04-01. Precision measurements of weak interaction parameters at Belle and Belle II. https://arxiv.org/abs/2504.00354

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