Speaker
Description
We propose a simultaneous analysis of $B \to D \ell \nu$ and $B\to D^{*} \ell \nu$ decays to measure model-independent observables for the determination of $|V_{cb}|$. The $B\to D^{*} \ell \nu$ decays is partially reconstructed, removing systematic uncertainty on $|V_{cb}|$ from the soft-pion reconstruction. By assuming equality of the semileptonic decay width of $B^0$ and $B^+$ mesons, we can also measure $f_{+-}/f_{00}$, the ratio of the branching fractions of the $\Upsilon(4{\rm S})$ decaying into charged and neutral $B\overline{B}$ pairs. From the model-independent observables, $|V_{cb}|$ and the form-factor parameters of both decays can be determined a-posteriori assuming any form-factor model and lattice data inputs. Using simulation, we present the potential of this analysis with the current Belle II dataset.
