# ICHEP 2020

July 28, 2020 to August 6, 2020
virtual conference
Europe/Prague timezone

## Study of $B \to D^* l \nu$ and $B \to D l \nu$ decays with a full angular analysis at BABAR

Jul 29, 2020, 4:15 PM
15m
virtual conference

#### virtual conference

Talk 05. Quark and Lepton Flavour Physics

### Speakers

Franco Simonetto (Universita' &amp; INFN Padova) Franco Simonetto (Universita e INFN, Padova (IT))

### Description

We present results on the first full 4-dimensional angular analysis of the $B -> D^* l \nu$ and $B -> D l \nu$ decays, using the $e^+e^-$ collision dataset collected by the $BABAR$ experiment at the $\Upsilon(4S)$resonance. One $B$ meson from the $\Upsilon(4S)\to B\bar{B}$ decay is fully reconstructed in a hadronic decay mode which constrains the kinematics and provides a precise determination of the neutrino momentum vector. We extract the underlying hadronic form-factors employing the model-independent BGL approach and a value for the $CKM$ matrix element $|V_{cb}|$. Last, employing our measured BGL form-factors, we provide new predictions within the Standard Model, for observables related to the the semi-tauonic decay $B -> D^* \tau \nu$.

### Primary author

Franco Simonetto (Universita' &amp; INFN Padova)