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arXiv · 1512.02145

Observation of the decay $B_s^0\rightarrow K^0\overline{K}^0$

Belle Collaboration·B. Pal·A. J. Schwartz·A. Abdesselam·I. Adachi·H. Aihara·D. M. Asner·T. Aushev·R. Ayad·T. Aziz·V. Babu·I. Badhrees·S. Bahinipati·A. M. Bakich·E. Barberio·P. Behera·V. Bhardwaj·B. Bhuyan·J. Biswal·A. Bobrov·A. Bozek·M. Bračko·T. E. Browder·D. Červenkov·V. Chekelian·A. Chen·B. G. Cheon·R. Chistov·K. Cho·V. Chobanova·Y. Choi·D. Cinabro·J. Dalseno·N. Dash·Z. Doležal·Z. Drásal·A. Drutskoy·D. Dutta·S. Eidelman·H. Farhat·J. E. Fast·B. G. Fulsom·V. Gaur·A. Garmash·R. Gillard·Y. M. Goh·P. Goldenzweig·D. Greenwald·O. Grzymkowska·J. Haba·T. Hara·K. Hayasaka·H. Hayashii·X. H. He·W. -S. Hou·K. Inami·A. Ishikawa·Y. Iwasaki·W. W. Jacobs·I. Jaegle·H. B. Jeon·D. Joffe·K. K. Joo·T. Julius·K. H. Kang·E. Kato·T. Kawasaki·C. Kiesling·D. Y. Kim·H. J. Kim·K. T. Kim·M. J. Kim·S. H. Kim·K. Kinoshita·P. Kodyš·S. Korpar·P. Križan·P. Krokovny·T. Kuhr·R. Kumar·T. Kumita·A. Kuzmin·Y. -J. Kwon·I. S. Lee·C. H. Li·H. Li·L. Li·L. Li Gioi·J. Libby·D. Liventsev·P. Lukin·T. Luo·M. Masuda·D. Matvienko·K. Miyabayashi·H. Miyata·R. Mizuk·G. B. Mohanty·S. Mohanty·A. Moll
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Abstract

We measure the decay $B_s^0\rightarrow K^0\overline{K}^0$ using data collected at the $Υ(5S)$ resonance with the Belle detector at the KEKB $e^+e^-$ collider. The data sample used corresponds to an integrated luminosity of 121.4 ${\rm fb^{-1}}$. We measure a branching fraction $\mathcal{B}(B_s^0\rightarrow K^0\overline{K}^0) = [19.6\,^{+5.8}_{-5.1}({\rm stat.})\,\pm1.0({\rm sys.})\,\pm 2.0(N^{}_{B_s^0\overline{B}_s^0})]\times 10^{-6}$ with a significance of 5.1 standard deviations. This measurement constitutes the first observation of this decay.

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Belle Collaboration, B. Pal, A. J. Schwartz, A. Abdesselam, I. Adachi, H. Aihara, D. M. Asner, T. Aushev, R. Ayad, T. Aziz, V. Babu, I. Badhrees, S. Bahinipati, A. M. Bakich, E. Barberio, P. Behera, V. Bhardwaj, B. Bhuyan, J. Biswal, A. Bobrov, A. Bozek, M. Bračko, T. E. Browder, D. Červenkov, V. Chekelian, A. Chen, B. G. Cheon, R. Chistov, K. Cho, V. Chobanova, Y. Choi, D. Cinabro, J. Dalseno, N. Dash, Z. Doležal, Z. Drásal, A. Drutskoy, D. Dutta, S. Eidelman, H. Farhat, J. E. Fast, B. G. Fulsom, V. Gaur, A. Garmash, R. Gillard, Y. M. Goh, P. Goldenzweig, D. Greenwald, O. Grzymkowska, J. Haba, T. Hara, K. Hayasaka, H. Hayashii, X. H. He, W. -S. Hou, K. Inami, A. Ishikawa, Y. Iwasaki, W. W. Jacobs, I. Jaegle, H. B. Jeon, D. Joffe, K. K. Joo, T. Julius, K. H. Kang, E. Kato, T. Kawasaki, C. Kiesling, D. Y. Kim, H. J. Kim, K. T. Kim, M. J. Kim, S. H. Kim, K. Kinoshita, P. Kodyš, S. Korpar, P. Križan, P. Krokovny, T. Kuhr, R. Kumar, T. Kumita, A. Kuzmin, Y. -J. Kwon, I. S. Lee, C. H. Li, H. Li, L. Li, L. Li Gioi, J. Libby, D. Liventsev, P. Lukin, T. Luo, M. Masuda, D. Matvienko, K. Miyabayashi, H. Miyata, R. Mizuk, G. B. Mohanty, S. Mohanty, A. Moll. 2016-04-20. Observation of the decay $B_s^0\rightarrow K^0\overline{K}^0$. https://doi.org/10.1103/physrevlett.116.161801

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