000002652 001__ 2652
000002652 005__ 20211123145059.0
000002652 037__ $$aBELLE2-CONF-PH-2021-013
000002652 041__ $$aeng
000002652 100__ $$aMoritz Bauer
000002652 245__ $$aExclusive $B \to X_u \ell \nu_\ell$ Decays with Hadronic Full-event-interpretation Tagging in 62.8\invfb of Belle II Data
000002652 260__ $$a$$c2021-09-09
000002652 300__ $$amult. p
000002652 520__ $$aWe present a reconstruction in early data of the semileptonic decay $B^+ \to \pi^0 \ell^+ \nu_\ell$, and first results of a reconstruction of the decays $B^+ \to \rho^0 \ell^+ \nu_\ell$ and $B^0 \to \rho^- \ell^+ \nu_\ell$ in a sample corresponding to 62.8\invfb of Belle II data using hadronic $B$-tagging via the full-event-interpretation algorithm. We determine the total branching fractions via fits to the distribution of the square of the missing mass, with \bfpiz{} = (8.29 $\pm$ 1.99$_{\mathrm{stat}}$ $\pm$ 0.46$_{\mathrm{sys}}$) $\times 10^{-5}$, \bfrhoz{} = ($9.26 \pm 6.33_{\mathrm{stat}}$ $\pm$ 0.38$_{\mathrm{sys}}$) $\times 10^{-5}$ and \bfrhoc = ($1.51 \pm 1.13_{\mathrm{stat}}$ $\pm$ 0.09$_{\mathrm{sys}}$) $\times 10^{-4}$. We also quote an updated branching fraction for the $B^0 \to \pi^- \ell^+ \nu_\ell$ decay, \bfpic{} = (1.47 $\pm$ 0.29$_{\mathrm{stat}}$ $\pm$ 0.05$_{\mathrm{sys}}$) $\times 10^{-4}$, based on the sum of the partial branching fractions in three bins of the momentum transfer to the leptonic system.
000002652 6531_ $$aFull-Event-Interpretation
000002652 6531_ $$aHadronic Tagging
000002652 6531_ $$aExclusive semi-leptonic
000002652 700__ $$aPablo Goldenzweig
000002652 700__ $$aNadia Toutounji
000002652 700__ $$aKevin Varvell
000002652 8560_ $$fntou5237@uni.sydney.edu.au
000002652 8564_ $$uhttps://docs.belle2.org/record/2652/files/BELLE2-CONF-PH-2021-013.pdf