000002084 001__ 2084
000002084 005__ 20200806135805.0
000002084 037__ $$aBELLE2-CONF-PH-2020-008
000002084 041__ $$aeng
000002084 100__ $$aFlorian Bernlochner
000002084 245__ $$aStudies of the semileptonic $\bar B^0\to D^{*+}\ell^-\bar\nu_\ell$ and $B^-\to D^{0}\ell^-\bar\nu_\ell$ decay processes with \mbox{34.6 fb$^{-1}$} of Belle II data
000002084 260__ $$a$$c2020-08-05
000002084 300__ $$a19
000002084 520__ $$aWe report measurements of the $\bar B^0\to D^{*+}\ell^-\bar\nu_\ell$ and $B^-\to D^{0}\ell^-\bar\nu_\ell$ processes using \mbox{34.6 fb$^{-1}$} of collision events recorded by the Belle~II experiment at the SuperKEKB asymmetric-energy $e^+ e^-$ collider. For the $B^-\to D^{0}\ell^-\bar\nu_\ell$ channel, we present first studies that isolate this decay from other semileptonic processes and backgrounds. We report a measurement of the $\bar B^0\to D^{*+}\ell^-\bar\nu_\ell$ branching fraction and obtain $\mathcal{B}(\bar B^0\to D^{*+}\ell^-\bar\nu_\ell) = \left(4.60 \pm 0.05_{\mathrm{stat}}\pm 0.17_{\mathrm{syst}} \pm 0.45_{\pi_s}\right)$ in agreement with the world average. Here the uncertainties are statistical, systematic, and related to slow pion reconstruction, respectively. The systematic uncertainties are limited by the statistics of auxiliary measurements and will improve in the future. We also report differential branching fractions in five bins of the hadronic recoil parameter $w$ for $\bar B^0\to D^{*+}\ell^-\bar\nu_\ell$, unfolded to account for resolution and efficiency effects. 
000002084 6531_ $$aSemileptonic decays, Vcb
000002084 700__ $$aLu Cao
000002084 700__ $$aDaniel Dorner
000002084 700__ $$aPhilipp Horak 
000002084 700__ $$aChaoyi Lyu
000002084 700__ $$aMinakshi Nayak
000002084 700__ $$aChristoph Schwanda
000002084 700__ $$aAbi Soffer
000002084 8560_ $$fflorian.bernlochner@desy.de
000002084 8564_ $$uhttps://docs.belle2.org/record/2084/files/BELLE2-CONF-PH-2020-008.pdf