Measurement of the semileptonic $\bar{B^0} \rightarrow D^{*} \ell \nu_{\ell}$ branching fraction with fully reconstructed $B$ meson decays and 34.6 fb$^{-1}$ of Belle~II data

Sumitted to PubDB: 2020-08-25

Category: Conference papers and plots, Visibility: Public

Tags: -

Authors	Kyle Amirie, Florian Bernlochner, Michael Eliachevitch, William Sutcliffe
Non-Belle II authors	Racha Cheaib, Hannah Wakeling
Date	2020-08-25
Belle II Number	BELLE2-CONF-PH-2020-009
Abstract	We present a first measurement of the $\bar{B^0} \rightarrow D^{*} \ell \nu_{\ell}$ branching fraction using fully reconstructed $B$ meson decays employing the Full Event Interpretation algorithm. Collision events corresponding to an integrated luminosity of \lumi are analyzed, which were recorded by the Belle~II detector operated at the SuperKEKB accelerator complex. We measure 4.51 \pm 0.41_{stat} \pm 0.27_{syst} \pm0.45_{\pi_s}, with the first and second error denoting the statistical and systematic uncertainty, respectively, and the third dominant uncertainty is from the slow pion reconstruction efficiency.