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arXiv · 1612.05014

Lepton-Flavor-Dependent Angular Analysis of $B\to K^\ast \ell^+\ell^-$

Belle Collaboration·S. Wehle·C. Niebuhr·S. Yashchenko·I. Adachi·H. Aihara·S. Al Said·D. M. Asner·V. Aulchenko·T. Aushev·R. Ayad·T. Aziz·V. Babu·A. M. Bakich·V. Bansal·E. Barberio·W. Bartel·P. Behera·B. Bhuyan·J. Biswal·A. Bobrov·A. Bondar·G. Bonvicini·A. Bozek·M. Bračko·T. E. Browder·D. Červenkov·P. Chang·V. Chekelian·A. Chen·B. G. Cheon·K. Chilikin·R. Chistov·K. Cho·Y. Choi·D. Cinabro·N. Dash·J. Dingfelder·Z. Drásal·D. Dutta·S. Eidelman·D. Epifanov·H. Farhat·J. E. Fast·T. Ferber·B. G. Fulsom·V. Gaur·N. Gabyshev·A. Garmash·R. Gillard·P. Goldenzweig·B. Golob·O. Grzymkowska·E. Guido·J. Haba·T. Hara·K. Hayasaka·H. Hayashii·M. T. Hedges·W. -S. Hou·C. -L. Hsu·T. Iijima·K. Inami·G. Inguglia·A. Ishikawa·R. Itoh·Y. Iwasaki·W. W. Jacobs·I. Jaegle·H. B. Jeon·Y. Jin·D. Joffe·K. K. Joo·T. Julius·A. B. Kaliyar·K. H. Kang·G. Karyan·P. Katrenko·T. Kawasaki·H. Kichimi·C. Kiesling·D. Y. Kim·H. J. Kim·J. B. Kim·K. T. Kim·M. J. Kim·S. H. Kim·K. Kinoshita·L. Koch·P. Kodyš·S. Korpar·D. Kotchetkov·P. Križan·P. Krokovny·T. Kuhr·R. Kulasiri·T. Kumita·A. Kuzmin·Y. -J. Kwon·J. S. Lange
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Abstract

We present a measurement of angular observables and a test of lepton flavor universality in the $B\to K^\ast \ell^+\ell^-$ decay, where $\ell$ is either $e$ or $\mu$. The analysis is performed on a data sample corresponding to an integrated luminosity of $711~\mathrm{fb}^{-1}$ containing $772\times 10^{6}$ $B\bar B$ pairs, collected at the $\Upsilon(4S)$ resonance with the Belle detector at the asymmetric-energy $e^+e^-$ collider KEKB. The result is consistent with Standard Model (SM) expectations, where the largest discrepancy from a SM prediction is observed in the muon modes with a local significance of $2.6\sigma$.

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Belle Collaboration, S. Wehle, C. Niebuhr, S. Yashchenko, I. Adachi, H. Aihara, S. Al Said, D. M. Asner, V. Aulchenko, T. Aushev, R. Ayad, T. Aziz, V. Babu, A. M. Bakich, V. Bansal, E. Barberio, W. Bartel, P. Behera, B. Bhuyan, J. Biswal, A. Bobrov, A. Bondar, G. Bonvicini, A. Bozek, M. Bračko, T. E. Browder, D. Červenkov, P. Chang, V. Chekelian, A. Chen, B. G. Cheon, K. Chilikin, R. Chistov, K. Cho, Y. Choi, D. Cinabro, N. Dash, J. Dingfelder, Z. Drásal, D. Dutta, S. Eidelman, D. Epifanov, H. Farhat, J. E. Fast, T. Ferber, B. G. Fulsom, V. Gaur, N. Gabyshev, A. Garmash, R. Gillard, P. Goldenzweig, B. Golob, O. Grzymkowska, E. Guido, J. Haba, T. Hara, K. Hayasaka, H. Hayashii, M. T. Hedges, W. -S. Hou, C. -L. Hsu, T. Iijima, K. Inami, G. Inguglia, A. Ishikawa, R. Itoh, Y. Iwasaki, W. W. Jacobs, I. Jaegle, H. B. Jeon, Y. Jin, D. Joffe, K. K. Joo, T. Julius, A. B. Kaliyar, K. H. Kang, G. Karyan, P. Katrenko, T. Kawasaki, H. Kichimi, C. Kiesling, D. Y. Kim, H. J. Kim, J. B. Kim, K. T. Kim, M. J. Kim, S. H. Kim, K. Kinoshita, L. Koch, P. Kodyš, S. Korpar, D. Kotchetkov, P. Križan, P. Krokovny, T. Kuhr, R. Kulasiri, T. Kumita, A. Kuzmin, Y. -J. Kwon, J. S. Lange. 2016-12-15. Lepton-Flavor-Dependent Angular Analysis of $B\to K^\ast \ell^+\ell^-$. https://arxiv.org/abs/1612.05014

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