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arXiv · 1604.04042

Angular analysis of $B^0 \to K^\ast(892)^0 \ell^+ \ell^-$

Belle Collaboration·A. Abdesselam·I. Adachi·K. Adamczyk·H. Aihara·S. Al Said·K. Arinstein·Y. Arita·D. M. Asner·T. Aso·H. Atmacan·V. Aulchenko·T. Aushev·R. Ayad·T. Aziz·V. Babu·I. Badhrees·S. Bahinipati·A. M. Bakich·A. Bala·Y. Ban·V. Bansal·E. Barberio·M. Barrett·W. Bartel·A. Bay·I. Bedny·P. Behera·M. Belhorn·K. Belous·D. Besson·V. Bhardwaj·B. Bhuyan·J. Biswal·T. Bloomfield·S. Blyth·A. Bobrov·A. Bondar·G. Bonvicini·C. Bookwalter·C. Boulahouache·A. Bozek·M. Bračko·F. Breibeck·J. Brodzicka·T. E. Browder·E. Waheed·D. Červenkov·M. -C. Chang·P. Chang·Y. Chao·V. Chekelian·A. Chen·K. -F. Chen·P. Chen·B. G. Cheon·K. Chilikin·R. Chistov·K. Cho·V. Chobanova·S. -K. Choi·Y. Choi·D. Cinabro·J. Crnkovic·J. Dalseno·M. Danilov·N. Dash·S. Di Carlo·J. Dingfelder·Z. Doležal·D. Dossett·Z. Drásal·A. Drutskoy·S. Dubey·D. Dutta·K. Dutta·S. Eidelman·D. Epifanov·S. Esen·H. Farhat·J. E. Fast·M. Feindt·T. Ferber·A. Frey·O. Frost·B. G. Fulsom·V. Gaur·N. Gabyshev·S. Ganguly·A. Garmash·D. Getzkow·R. Gillard·F. Giordano·R. Glattauer·Y. M. Goh·P. Goldenzweig·B. Golob·D. Greenwald·M. Grosse Perdekamp·J. Grygier
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Abstract

We present a measurement of angular observables, $P_4'$, $P_5'$, $P_6'$, $P_8'$, in the decay $B^0 \to K^\ast(892)^0 \ell^+ \ell^-$, where $\ell^+\ell^-$ is either $e^+e^-$ or $\mu^+\mu^-$. 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. Four angular observables, $P_{4,5,6,8}'$ are extracted in five bins of the invariant mass squared of the lepton system, $q^2$. We compare our results for $P_{4,5,6,8}'$ with Standard Model predictions including the $q^2$ region in which the LHCb collaboration reported the so-called $P_5'$ anomaly.

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Belle Collaboration, A. Abdesselam, I. Adachi, K. Adamczyk, H. Aihara, S. Al Said, K. Arinstein, Y. Arita, D. M. Asner, T. Aso, H. Atmacan, V. Aulchenko, T. Aushev, R. Ayad, T. Aziz, V. Babu, I. Badhrees, S. Bahinipati, A. M. Bakich, A. Bala, Y. Ban, V. Bansal, E. Barberio, M. Barrett, W. Bartel, A. Bay, I. Bedny, P. Behera, M. Belhorn, K. Belous, D. Besson, V. Bhardwaj, B. Bhuyan, J. Biswal, T. Bloomfield, S. Blyth, A. Bobrov, A. Bondar, G. Bonvicini, C. Bookwalter, C. Boulahouache, A. Bozek, M. Bračko, F. Breibeck, J. Brodzicka, T. E. Browder, E. Waheed, D. Červenkov, M. -C. Chang, P. Chang, Y. Chao, V. Chekelian, A. Chen, K. -F. Chen, P. Chen, B. G. Cheon, K. Chilikin, R. Chistov, K. Cho, V. Chobanova, S. -K. Choi, Y. Choi, D. Cinabro, J. Crnkovic, J. Dalseno, M. Danilov, N. Dash, S. Di Carlo, J. Dingfelder, Z. Doležal, D. Dossett, Z. Drásal, A. Drutskoy, S. Dubey, D. Dutta, K. Dutta, S. Eidelman, D. Epifanov, S. Esen, H. Farhat, J. E. Fast, M. Feindt, T. Ferber, A. Frey, O. Frost, B. G. Fulsom, V. Gaur, N. Gabyshev, S. Ganguly, A. Garmash, D. Getzkow, R. Gillard, F. Giordano, R. Glattauer, Y. M. Goh, P. Goldenzweig, B. Golob, D. Greenwald, M. Grosse Perdekamp, J. Grygier. 2016-04-14. Angular analysis of $B^0 \to K^\ast(892)^0 \ell^+ \ell^-$. https://arxiv.org/abs/1604.04042

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