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arXiv · 1110.0730

Search for the lepton number violating decays $B^{+}\to π^- μ^+ μ^+$ and $B^{+}\to K^- μ^+ μ^+$

The LHCb Collaboration·R. Aaij·C. Abellan Beteta·B. Adeva·M. Adinolfi·C. Adrover·A. Affolder·Z. Ajaltouni·J. Albrecht·F. Alessio·M. Alexander·G. Alkhazov·P. Alvarez Cartelle·A. A. Alves Jr·S. Amato·Y. Amhis·J. Anderson·R. B. Appleby·O. Aquines Gutierrez·F. Archilli·L. Arrabito·A. Artamonov·M. Artuso·E. Aslanides·G. Auriemma·S. Bachmann·J. J. Back·D. S. Bailey·V. Balagura·W. Baldini·R. J. Barlow·C. Barschel·S. Barsuk·W. Barter·A. Bates·C. Bauer·Th. Bauer·A. Bay·I. Bediaga·K. Belous·I. Belyaev·E. Ben-Haim·M. Benayoun·G. Bencivenni·S. Benson·J. Benton·R. Bernet·M. -O. Bettler·M. van Beuzekom·A. Bien·S. Bifani·A. Bizzeti·P. M. Bjørnstad·T. Blake·F. Blanc·C. Blanks·J. Blouw·S. Blusk·A. Bobrov·V. Bocci·A. Bondar·N. Bondar·W. Bonivento·S. Borghi·A. Borgia·T. J. V. Bowcock·C. Bozzi·T. Brambach·J. van den Brand·J. Bressieux·D. Brett·S. Brisbane·M. Britsch·T. Britton·N. H. Brook·H. Brown·A. Büchler-Germann·I. Burducea·A. Bursche·J. Buytaert·S. Cadeddu·J. M. Caicedo Carvajal·O. Callot·M. Calvi·M. Calvo Gomez·A. Camboni·P. Campana·A. Carbone·G. Carboni·R. Cardinale·A. Cardini·L. Carson·K. Carvalho Akiba·G. Casse·M. Cattaneo·M. Charles·Ph. Charpentier·N. Chiapolini·K. Ciba·X. Cid Vidal
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Abstract

A search is performed for the lepton number violating decay $B^{+}\to h^- μ^+ μ^+$, where $h^-$ represents a $K^-$ or a $π^-$, using data from the LHCb detector corresponding to an integrated luminosity of $36pb^{-1}$. The decay is forbidden in the Standard Model but allowed in models with a Majorana neutrino. No signal is observed in either channel and limits of $B(B^{+} \to K^- μ^+ μ^+) < 5.4\times 10^{-8}$ and $B(B^{+} \to π^- μ^+ μ^+) < 5.8\times 10^{-8}$ are set at the 95% confidence level. These improve the previous best limits by factors of 40 and 30, respectively.

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The LHCb Collaboration, R. Aaij, C. Abellan Beteta, B. Adeva, M. Adinolfi, C. Adrover, A. Affolder, Z. Ajaltouni, J. Albrecht, F. Alessio, M. Alexander, G. Alkhazov, P. Alvarez Cartelle, A. A. Alves Jr, S. Amato, Y. Amhis, J. Anderson, R. B. Appleby, O. Aquines Gutierrez, F. Archilli, L. Arrabito, A. Artamonov, M. Artuso, E. Aslanides, G. Auriemma, S. Bachmann, J. J. Back, D. S. Bailey, V. Balagura, W. Baldini, R. J. Barlow, C. Barschel, S. Barsuk, W. Barter, A. Bates, C. Bauer, Th. Bauer, A. Bay, I. Bediaga, K. Belous, I. Belyaev, E. Ben-Haim, M. Benayoun, G. Bencivenni, S. Benson, J. Benton, R. Bernet, M. -O. Bettler, M. van Beuzekom, A. Bien, S. Bifani, A. Bizzeti, P. M. Bjørnstad, T. Blake, F. Blanc, C. Blanks, J. Blouw, S. Blusk, A. Bobrov, V. Bocci, A. Bondar, N. Bondar, W. Bonivento, S. Borghi, A. Borgia, T. J. V. Bowcock, C. Bozzi, T. Brambach, J. van den Brand, J. Bressieux, D. Brett, S. Brisbane, M. Britsch, T. Britton, N. H. Brook, H. Brown, A. Büchler-Germann, I. Burducea, A. Bursche, J. Buytaert, S. Cadeddu, J. M. Caicedo Carvajal, O. Callot, M. Calvi, M. Calvo Gomez, A. Camboni, P. Campana, A. Carbone, G. Carboni, R. Cardinale, A. Cardini, L. Carson, K. Carvalho Akiba, G. Casse, M. Cattaneo, M. Charles, Ph. Charpentier, N. Chiapolini, K. Ciba, X. Cid Vidal. 2012-07-18. Search for the lepton number violating decays $B^{+}\to π^- μ^+ μ^+$ and $B^{+}\to K^- μ^+ μ^+$. https://doi.org/10.1103/physrevlett.108.101601

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