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arXiv · 2001.10354

Constraints on the $K^0_{\mathrm{S}}\rightarrow\mu^{+}\mu^{-}$ branching fraction

LHCb collaboration·R. Aaij·C. Abellán Beteta·T. Ackernley·B. Adeva·M. Adinolfi·H. Afsharnia·C. A. Aidala·S. Aiola·Z. Ajaltouni·S. Akar·P. Albicocco·J. Albrecht·F. Alessio·M. Alexander·A. Alfonso Albero·G. Alkhazov·P. Alvarez Cartelle·A. A. Alves Jr·S. Amato·Y. Amhis·L. An·L. Anderlini·G. Andreassi·M. Andreotti·F. Archilli·J. Arnau Romeu·A. Artamonov·M. Artuso·K. Arzymatov·E. Aslanides·M. Atzeni·B. Audurier·S. Bachmann·J. J. Back·S. Baker·V. Balagura·W. Baldini·A. Baranov·R. J. Barlow·S. Barsuk·W. Barter·M. Bartolini·F. Baryshnikov·G. Bassi·V. Batozskaya·B. Batsukh·A. Battig·A. Bay·M. Becker·F. Bedeschi·I. Bediaga·A. Beiter·L. J. Bel·V. Belavin·S. Belin·N. Beliy·V. Bellee·K. Belous·I. Belyaev·G. Bencivenni·E. Ben-Haim·S. Benson·S. Beranek·A. Berezhnoy·R. Bernet·D. Berninghoff·H. C. Bernstein·C. Bertella·E. Bertholet·A. Bertolin·C. Betancourt·F. Betti·M. O. Bettler·Ia. Bezshyiko·S. Bhasin·J. Bhom·M. S. Bieker·S. Bifani·P. Billoir·A. Bizzeti·M. Bjørn·M. P. Blago·T. Blake·F. Blanc·S. Blusk·D. Bobulska·V. Bocci·O. Boente Garcia·T. Boettcher·A. Boldyrev·A. Bondar·N. Bondar·S. Borghi·M. Borisyak·M. Borsato·J. T. Borsuk·T. J. V. Bowcock·C. Bozzi·M. J. Bradley
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Abstract

A search for the decay $K^0_{\mathrm{S}}\rightarrow\mu^{+}\mu^{-}$ is performed using proton-proton collision data, corresponding to an integrated luminosity of $5.6\,\text{fb}^{-1}$ and collected with the LHCb experiment during 2016, 2017 and 2018 at a center-of-mass energy of $13\,\mathrm{TeV}$. The observed signal yield is consistent with zero, yielding an upper limit of ${\cal B}(K^0_{\mathrm{S}}\rightarrow\mu^{+}\mu^{-}) < 2.2 \times 10^{-10}$ at 90% CL. The limit reduces to ${\cal B}(K^0_{\mathrm{S}}\rightarrow\mu^{+}\mu^{-}) < 2.1 \times 10^{-10}$ at 90% CL once combined with the result from data taken in 2011 and 2012.

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LHCb collaboration, R. Aaij, C. Abellán Beteta, T. Ackernley, B. Adeva, M. Adinolfi, H. Afsharnia, C. A. Aidala, S. Aiola, Z. Ajaltouni, S. Akar, P. Albicocco, J. Albrecht, F. Alessio, M. Alexander, A. Alfonso Albero, G. Alkhazov, P. Alvarez Cartelle, A. A. Alves Jr, S. Amato, Y. Amhis, L. An, L. Anderlini, G. Andreassi, M. Andreotti, F. Archilli, J. Arnau Romeu, A. Artamonov, M. Artuso, K. Arzymatov, E. Aslanides, M. Atzeni, B. Audurier, S. Bachmann, J. J. Back, S. Baker, V. Balagura, W. Baldini, A. Baranov, R. J. Barlow, S. Barsuk, W. Barter, M. Bartolini, F. Baryshnikov, G. Bassi, V. Batozskaya, B. Batsukh, A. Battig, A. Bay, M. Becker, F. Bedeschi, I. Bediaga, A. Beiter, L. J. Bel, V. Belavin, S. Belin, N. Beliy, V. Bellee, K. Belous, I. Belyaev, G. Bencivenni, E. Ben-Haim, S. Benson, S. Beranek, A. Berezhnoy, R. Bernet, D. Berninghoff, H. C. Bernstein, C. Bertella, E. Bertholet, A. Bertolin, C. Betancourt, F. Betti, M. O. Bettler, Ia. Bezshyiko, S. Bhasin, J. Bhom, M. S. Bieker, S. Bifani, P. Billoir, A. Bizzeti, M. Bjørn, M. P. Blago, T. Blake, F. Blanc, S. Blusk, D. Bobulska, V. Bocci, O. Boente Garcia, T. Boettcher, A. Boldyrev, A. Bondar, N. Bondar, S. Borghi, M. Borisyak, M. Borsato, J. T. Borsuk, T. J. V. Bowcock, C. Bozzi, M. J. Bradley. 2020-01-28. Constraints on the $K^0_{\mathrm{S}}\rightarrow\mu^{+}\mu^{-}$ branching fraction. https://doi.org/10.1103/physrevlett.125.231801

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