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M. T. Prim, F. U. Bernlochner, F. Metzner, K. Lieret, T. Kuhr, I. Adachi, H. Aihara, S. Al Said, D. M. Asner, H. Atmacan, V. Aulchenko, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, Sw. Banerjee, M. Bauer, P. K. Behera, J. V. Bennett, M. Bessner, V. Bhardwaj, B. Bhuyan, T. Bilka, D. Biswas, D. Bodrov, J. Borah, A. Bożek, M. Bračko, P. Branchini, T. E. Browder, A. Budano, M. Campajola, L. Cao, D. Červenkov, M.-C. Chang, V. Chekelian, B. G. Cheon, K. Chilikin, H.-E. Cho, K. Cho, Y. Choi, S. Choudhury, D. Cinabro, S. Das, N. Dash, G. de Marino, G. De Nardo, G. De Pietro, R. Dhamija, F. Di Capua, J. Dingfelder, Z. Doležal, T. V. Dong, D. Epifanov, T. Ferber, D. Ferlewicz, A. Frey, B. G. Fulsom, V. Gaur, A. Garmash, A. Giri, P. Goldenzweig, E. Graziani, T. Gu, K. Gudkova, C. Hadjivasiliou, S. Halder, T. Hara, K. Hayasaka, H. Hayashii, M. T. Hedges, D. Herrmann, M. Hernández Villanueva, C.-L. Hsu, T. Iijima, K. Inami, G. Inguglia, N. Ipsita, A. Ishikawa, R. Itoh, M. Iwasaki, W. W. Jacobs, E.-J. Jang, S. Jia, Y. Jin, K. K. Joo, A. B. Kaliyar, K. H. Kang, T. Kawasaki, C. Kiesling, C. H. Kim, D. Y. Kim, K.-H. Kim, Y.-K. Kim, K. Kinoshita, P. Kodyš, T. Konno, A. Korobov, S. Korpar, E. Kovalenko
Abstract
We present a measurement of the differential shapes of exclusive $B\ensuremath{\rightarrow}{D}^{*}\ensuremath{\ell}{\overline{\ensuremath{\nu}}}_{\ensuremath{\ell}}$ ($B={B}^{\ensuremath{-}},{\overline{B}}^{0}$ and $\ensuremath{\ell}=e$, $\ensuremath{\mu}$) decays with hadronic tag-side reconstruction for the full $711\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ Belle dataset. We extract the Caprini-Lellouch-Neubert (CLN) and Boyd-Grinstein-Lebed (BGL) form factor parameters and use an external input for the absolute branching fractions to determine the Cabibbo-Kobayashi-Maskawa matrix element and find $|{V}_{cb}{|}_{\mathrm{CLN}}=(40.2\ifmmode\pm\else\textpm\fi{}0.9)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ and $|{V}_{cb}{|}_{\mathrm{BGL}}=(40.7\ifmmode\pm\else\textpm\fi{}1.0)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ with the zero-recoil lattice QCD point $\mathcal{F}(1)=0.906\ifmmode\pm\else\textpm\fi{}0.013$. We also perform a study of the impact of beyond zero-recoil lattice QCD calculations on the $|{V}_{cb}|$ determinations. Additionally, we present the lepton-flavor universality ratio ${R}_{e\ensuremath{\mu}}=\mathcal{B}(B\ensuremath{\rightarrow}{D}^{*}e{\overline{\ensuremath{\nu}}}_{e})/\mathcal{B}(B\ensuremath{\rightarrow}{D}^{*}\ensuremath{\mu}{\overline{\ensuremath{\nu}}}_{\ensuremath{\mu}})=0.993\ifmmode\pm\else\textpm\fi{}0.023\ifmmode\pm\else\textpm\fi{}0.023$, the electron and muon forward-backward asymmetry and their difference $\mathrm{\ensuremath{\Delta}}{A}_{FB}=0.028\ifmmode\pm\else\textpm\fi{}0.028\ifmmode\pm\else\textpm\fi{}0.008$, and the electron and muon ${D}^{*}$ longitudinal polarization fraction and their difference $\mathrm{\ensuremath{\Delta}}{F}_{L}^{{D}^{*}}=0.030\ifmmode\pm\else\textpm\fi{}0.025\ifmmode\pm\else\textpm\fi{}0.007$. The uncertainties quoted correspond to the statistical and systematic uncertainties, respectively.