Measurement of the branching fractions of the $B^{+}\to \eta {\ell }^{+}{\nu }_{\ell }$ and $B^{+}\to {\eta }^{\prime }{\ell }^{+}{\nu }_{\ell }$ decays with signal-side only reconstruction in the full $q^2$ range

Belle Collaboration, U. Gebauer, C. Beleño +210

The branching fractions of the decays $B^{+}\to \eta {\ell }^{+}{\nu }_{\ell }$ and $B^{+}\to {\eta }^{\prime }{\ell }^{+}{\nu }_{\ell }$ are measured, where $\ell$ is either an electron or a muon, using…