Improved Measurements of Branching Fractions for B->Kpi, pipi and KK Decays

TL;DR

This paper presents improved measurements of B meson decay branching fractions using a larger data sample, providing more precise results that help constrain CKM angles and hadronic uncertainties in CP violation studies.

Contribution

It offers the most precise measurements to date of specific B decay modes, with a significantly larger dataset than previous studies, enhancing the understanding of CKM parameters.

Findings

Clear signals for B→Kπ, π+π−, and π+π0 decays

Upper limits set on B→K K̄ decays

Results constrain CKM angle φ3 and hadronic uncertainties

Abstract

We report improved measurements of branching fractions for $B\to K\pi$, $\pi^+\pi^-$, $\pi^+\pi^0$ and $K\bar{K}$ decays based on a data sample of 85.0 million $B\bar{B}$ pairs collected at the $\Upsilon (4S)$ resonance with the Belle detector at the KEKB $e^+e^-$ storage ring. This data sample is almost three times larger than the sample previously used. We observe clear signals for $B\to K\pi$, $\pi^+\pi^-$ and $\pi^+\pi^0$ decays and set upper limits on $B\to K\bar{K}$ decays. The results can be used to give model-dependent constraints on the CKM angle $\phi_3$, as well as limits on the hadronic uncertainty in the time-dependent analysis of the angle $\phi_2$.