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arXiv · 1411.4413

Observation of the rare $B^0_s\to\mu^+\mu^-$ decay from the combined analysis of CMS and LHCb data

The CMS·LHCb Collaborations·:·V. Khachatryan·A. M. Sirunyan·A. Tumasyan·W. Adam·T. Bergauer·M. Dragicevic·J. Erö·M. Friedl·R. Frühwirth·V. M. Ghete·C. Hartl·N. Hörmann·J. Hrubec·M. Jeitler·W. Kiesenhofer·V. Knünz·M. Krammer·I. Krätschmer·D. Liko·I. Mikulec·D. Rabady·B. Rahbaran·H. Rohringer·R. Schöfbeck·J. Strauss·W. Treberer-Treberspurg·W. Waltenberger·C. -E. Wulz·V. Mossolov·N. Shumeiko·J. Suarez Gonzalez·S. Alderweireldt·S. Bansal·T. Cornelis·E. A. De Wolf·X. Janssen·A. Knutsson·J. Lauwers·S. Luyckx·S. Ochesanu·R. Rougny·M. Van De Klundert·H. Van Haevermaet·P. Van Mechelen·N. Van Remortel·A. Van Spilbeeck·F. Blekman·S. Blyweert·J. D'Hondt·N. Daci·N. Heracleous·J. Keaveney·S. Lowette·M. Maes·A. Olbrechts·Q. Python·D. Strom·S. Tavernier·W. Van Doninck·P. Van Mulders·G. P. Van Onsem·I. Villella·C. Caillol·B. Clerbaux·G. De Lentdecker·D. Dobur·L. Favart·A. P. R. Gay·A. Grebenyuk·A. Léonard·A. Mohammadi·L. Perniè·A. Randle-conde·T. Reis·T. Seva·L. Thomas·C. Vander Velde·P. Vanlaer·J. Wang·F. Zenoni·V. Adler·K. Beernaert·L. Benucci·A. Cimmino·S. Costantini·S. Crucy·S. Dildick·A. Fagot·G. Garcia·J. Mccartin·A. A. Ocampo Rios·D. Ryckbosch·S. Salva Diblen·M. Sigamani·N. Strobbe·F. Thyssen·M. Tytgat
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Abstract

A joint measurement is presented of the branching fractions $B^0_s\to\mu^+\mu^-$ and $B^0\to\mu^+\mu^-$ in proton-proton collisions at the LHC by the CMS and LHCb experiments. The data samples were collected in 2011 at a centre-of-mass energy of 7 TeV, and in 2012 at 8 TeV. The combined analysis produces the first observation of the $B^0_s\to\mu^+\mu^-$ decay, with a statistical significance exceeding six standard deviations, and the best measurement of its branching fraction so far. Furthermore, evidence for the $B^0\to\mu^+\mu^-$ decay is obtained with a statistical significance of three standard deviations. The branching fraction measurements are statistically compatible with SM predictions and impose stringent constraints on several theories beyond the SM.

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The CMS, LHCb Collaborations, :, V. Khachatryan, A. M. Sirunyan, A. Tumasyan, W. Adam, T. Bergauer, M. Dragicevic, J. Erö, M. Friedl, R. Frühwirth, V. M. Ghete, C. Hartl, N. Hörmann, J. Hrubec, M. Jeitler, W. Kiesenhofer, V. Knünz, M. Krammer, I. Krätschmer, D. Liko, I. Mikulec, D. Rabady, B. Rahbaran, H. Rohringer, R. Schöfbeck, J. Strauss, W. Treberer-Treberspurg, W. Waltenberger, C. -E. Wulz, V. Mossolov, N. Shumeiko, J. Suarez Gonzalez, S. Alderweireldt, S. Bansal, T. Cornelis, E. A. De Wolf, X. Janssen, A. Knutsson, J. Lauwers, S. Luyckx, S. Ochesanu, R. Rougny, M. Van De Klundert, H. Van Haevermaet, P. Van Mechelen, N. Van Remortel, A. Van Spilbeeck, F. Blekman, S. Blyweert, J. D'Hondt, N. Daci, N. Heracleous, J. Keaveney, S. Lowette, M. Maes, A. Olbrechts, Q. Python, D. Strom, S. Tavernier, W. Van Doninck, P. Van Mulders, G. P. Van Onsem, I. Villella, C. Caillol, B. Clerbaux, G. De Lentdecker, D. Dobur, L. Favart, A. P. R. Gay, A. Grebenyuk, A. Léonard, A. Mohammadi, L. Perniè, A. Randle-conde, T. Reis, T. Seva, L. Thomas, C. Vander Velde, P. Vanlaer, J. Wang, F. Zenoni, V. Adler, K. Beernaert, L. Benucci, A. Cimmino, S. Costantini, S. Crucy, S. Dildick, A. Fagot, G. Garcia, J. Mccartin, A. A. Ocampo Rios, D. Ryckbosch, S. Salva Diblen, M. Sigamani, N. Strobbe, F. Thyssen, M. Tytgat. 2014-11-17. Observation of the rare $B^0_s\to\mu^+\mu^-$ decay from the combined analysis of CMS and LHCb data. https://doi.org/10.1038/nature14474

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