Measurement of exclusive $B \to X_u \ell \nu$ decays using a full-reconstruction tag at Belle

TL;DR

This study measures the branching fractions and q^2 distributions of exclusive charmless semileptonic B decays using full reconstruction tagging at Belle, providing insights into B meson decay dynamics.

Contribution

It presents the first measurement of these decay properties using a large data sample and full reconstruction tagging at Belle, improving precision over previous methods.

Findings

Measured branching fractions of exclusive B decays.

Analyzed q^2 distributions for decay dynamics.

Utilized a large dataset of 535 million B pairs.

Abstract

We report a preliminary study of the branching fractions and $q^2$ distributions of exclusive charmless semileptonic B decays, using events tagged by fully reconstructing one of the $B$ mesons in a hadronic decay mode. These results are obtained from a data sample that contains 535 $\times 10^6\ B\bar{B}$ pairs, collected near the $\Upsilon(4S)$ resonance with the Belle detector at the KEKB asymmetric energy $e^+ e^-$ collider.