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arXiv · 2110.03871

Search for the decay $B^{0}\rightarrow K^{\ast 0}\tau^{+}\tau^{-}$ at the Belle experiment

Belle Collaboration·T. V. Dong·T. Luo·I. Adachi·H. Aihara·D. M. Asner·H. Atmacan·V. Aulchenko·T. Aushev·R. Ayad·V. Babu·S. Bahinipati·P. Behera·K. Belous·F. Bernlochner·M. Bessner·B. Bhuyan·T. Bilka·J. Biswal·A. Bobrov·A. Bozek·M. Bračko·P. Branchini·T. E. Browder·A. Budano·M. Campajola·D. Červenkov·M. -C. Chang·P. Chang·A. Chen·B. G. Cheon·K. Chilikin·H. E. Cho·K. Cho·S. -J. Cho·S. -K. Choi·Y. Choi·S. Choudhury·D. Cinabro·S. Cunliffe·T. Czank·S. Das·G. De Nardo·G. De Pietro·R. Dhamija·F. Di Capua·J. Dingfelder·Z. Doležal·S. Dubey·D. Epifanov·T. Ferber·D. Ferlewicz·B. G. Fulsom·R. Garg·V. Gaur·N. Gabyshev·A. Garmash·A. Giri·P. Goldenzweig·E. Graziani·T. Gu·K. Gudkova·T. Hara·O. Hartbrich·K. Hayasaka·M. Hernandez Villanueva·W. -S. Hou·C. -L. Hsu·K. Inami·G. Inguglia·A. Ishikawa·R. Itoh·M. Iwasaki·W. W. Jacobs·E. -J. Jang·S. Jia·Y. Jin·K. K. Joo·J. Kahn·K. H. Kang·H. Kichimi·C. Kiesling·C. H. Kim·D. Y. Kim·K. T. Kim·S. H. Kim·Y. -K. Kim·T. D. Kimmel·P. Kodyš·T. Konno·A. Korobov·S. Korpar·E. Kovalenko·P. Križan·R. Kroeger·P. Krokovny·T. Kuhr·R. Kulasiri·M. Kumar·R. Kumar
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Abstract

This letter presents a search for the rare flavor-changing neutral current process $B^{0}\rightarrow K^{\ast 0}\tau^{+}\tau^{-}$ using data taken with the Belle detector at the KEKB asymmetric energy $e^{+}e^{-}$ collider. The analysis is based on the entire $\Upsilon(4S)$ resonance data sample of 711 $\rm fb^{-1}$, corresponding to $772\times 10^{6} B \bar{B}$ pairs. In our search we fully reconstruct the companion $B$ meson produced in the process $e^{+}e^{-}\rightarrow\Upsilon(4S)\rightarrow B\bar{B}$ from its hadronic decay modes, and look for the decay $B^{0}\rightarrow K^{\ast 0}\tau^{+}\tau^{-}$ in the rest of the event. No evidence for a signal is found. We report an upper limit on the branching fraction $\mathcal{B}({B^{0}\rightarrow K^{\ast 0}\tau^{+}\tau^{-}})<3.1\times 10^{-3}$ at 90\% confidence level. This is the first direct limit on $\mathcal{B}({B^{0}\rightarrow K^{\ast 0}\tau^{+}\tau^{-}})$.

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Belle Collaboration, T. V. Dong, T. Luo, I. Adachi, H. Aihara, D. M. Asner, H. Atmacan, V. Aulchenko, T. Aushev, R. Ayad, V. Babu, S. Bahinipati, P. Behera, K. Belous, F. Bernlochner, M. Bessner, B. Bhuyan, T. Bilka, J. Biswal, A. Bobrov, A. Bozek, M. Bračko, P. Branchini, T. E. Browder, A. Budano, M. Campajola, D. Červenkov, M. -C. Chang, P. Chang, A. Chen, B. G. Cheon, K. Chilikin, H. E. Cho, K. Cho, S. -J. Cho, S. -K. Choi, Y. Choi, S. Choudhury, D. Cinabro, S. Cunliffe, T. Czank, S. Das, G. De Nardo, G. De Pietro, R. Dhamija, F. Di Capua, J. Dingfelder, Z. Doležal, S. Dubey, D. Epifanov, T. Ferber, D. Ferlewicz, B. G. Fulsom, R. Garg, V. Gaur, N. Gabyshev, A. Garmash, A. Giri, P. Goldenzweig, E. Graziani, T. Gu, K. Gudkova, T. Hara, O. Hartbrich, K. Hayasaka, M. Hernandez Villanueva, W. -S. Hou, C. -L. Hsu, K. Inami, G. Inguglia, A. Ishikawa, R. Itoh, M. Iwasaki, W. W. Jacobs, E. -J. Jang, S. Jia, Y. Jin, K. K. Joo, J. Kahn, K. H. Kang, H. Kichimi, C. Kiesling, C. H. Kim, D. Y. Kim, K. T. Kim, S. H. Kim, Y. -K. Kim, T. D. Kimmel, P. Kodyš, T. Konno, A. Korobov, S. Korpar, E. Kovalenko, P. Križan, R. Kroeger, P. Krokovny, T. Kuhr, R. Kulasiri, M. Kumar, R. Kumar. 2021-10-08. Search for the decay $B^{0}\rightarrow K^{\ast 0}\tau^{+}\tau^{-}$ at the Belle experiment. https://doi.org/10.1103/physrevd.108.l011102

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