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arXiv · 2301.03768

Search for lepton-flavor-violating $\tau$ decays into a lepton and a vector meson using the full Belle data sample

Belle Collaboration·N. Tsuzuki·K. Inami·I. Adachi·H. Aihara·D. M. Asner·H. Atmacan·T. Aushev·R. Ayad·V. Babu·Sw. Banerjee·P. Behera·K. Belous·J. Bennett·M. Bessner·B. Bhuyan·T. Bilka·D. Biswas·D. Bodrov·J. Borah·A. Bozek·M. Bračko·P. Branchini·T. E. Browder·A. Budano·M. Campajola·D. Červenkov·M. -C. Chang·B. G. Cheon·K. Chilikin·H. E. Cho·K. Cho·S. -J. Cho·S. -K. Choi·Y. Choi·S. Choudhury·D. Cinabro·J. Cochran·S. Das·N. Dash·G. De Nardo·G. De Pietro·R. Dhamija·F. Di Capua·Z. Doležal·T. V. Dong·D. Dossett·S. Dubey·D. Epifanov·T. Ferber·D. Ferlewicz·B. G. Fulsom·V. Gaur·A. Giri·P. Goldenzweig·Y. Guan·K. Gudkova·X. Han·T. Hara·K. Hayasaka·H. Hayashii·M. T. Hedges·D. Herrmann·W. -S. Hou·C. -L. Hsu·T. Iijima·N. Ipsita·A. Ishikawa·R. Itoh·M. Iwasaki·W. W. Jacobs·E. -J. Jang·S. Jia·Y. Jin·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·P. Križan·P. Krokovny·M. Kumar·K. Kumara·A. Kuzmin·Y. -J. Kwon·S. C. Lee·J. Li·L. K. Li·Y. Li·J. Libby·K. Lieret·Y. -R. Lin·D. Liventsev
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Abstract

Charged-lepton-flavor-violation is predicted in several new physics scenarios. We update the analysis of $\tau$ lepton decays into a light charged lepton ($\ell$ = $e^{\pm}$ or $\mu^{\pm}$) and a vector meson ($V^0$ = $\rho^0$, $\phi$, $\omega$, $K^{\ast0}$, or $\overline{K}{}^{\ast0}$) using 980 fb$^{-1}$ of data collected with the Belle detector at the KEKB collider. No significant excess of such signal events is observed, and thus 90% credibility level upper limits are set on the $\tau \rightarrow \ell V^0$ branching fractions in the range of (1.7--$4.3) \times 10^{-8}$. These limits are improved by 30% on average from the previous results.

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Belle Collaboration, N. Tsuzuki, K. Inami, I. Adachi, H. Aihara, D. M. Asner, H. Atmacan, T. Aushev, R. Ayad, V. Babu, Sw. Banerjee, P. Behera, K. Belous, J. Bennett, M. Bessner, B. Bhuyan, T. Bilka, D. Biswas, D. Bodrov, J. Borah, A. Bozek, M. Bračko, P. Branchini, T. E. Browder, A. Budano, M. Campajola, D. Červenkov, M. -C. Chang, B. G. Cheon, K. Chilikin, H. E. Cho, K. Cho, S. -J. Cho, S. -K. Choi, Y. Choi, S. Choudhury, D. Cinabro, J. Cochran, S. Das, N. Dash, G. De Nardo, G. De Pietro, R. Dhamija, F. Di Capua, Z. Doležal, T. V. Dong, D. Dossett, S. Dubey, D. Epifanov, T. Ferber, D. Ferlewicz, B. G. Fulsom, V. Gaur, A. Giri, P. Goldenzweig, Y. Guan, K. Gudkova, X. Han, T. Hara, K. Hayasaka, H. Hayashii, M. T. Hedges, D. Herrmann, W. -S. Hou, C. -L. Hsu, T. Iijima, N. Ipsita, A. Ishikawa, R. Itoh, M. Iwasaki, W. W. Jacobs, E. -J. Jang, S. Jia, Y. Jin, 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, P. Križan, P. Krokovny, M. Kumar, K. Kumara, A. Kuzmin, Y. -J. Kwon, S. C. Lee, J. Li, L. K. Li, Y. Li, J. Libby, K. Lieret, Y. -R. Lin, D. Liventsev. 2023-01-10. Search for lepton-flavor-violating $\tau$ decays into a lepton and a vector meson using the full Belle data sample. https://doi.org/10.1007/jhep06(2023)118

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