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$B to K^*(to Kpi) ell^+ell^-$ theory and the global picture: Whats next?

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 نشر من قبل Joaquim Matias
 تاريخ النشر 2016
  مجال البحث
والبحث باللغة English
 تأليف Bernat Capdevila




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The present status of the LHC anomalies found in exclusive semileptonic $bto sell^+ell^-$ decays is discussed with special emphasis on the exclusive 4-body angular distribution $B to K^*(to Kpi)ell^+ell^-$. The treatment of hadronic uncertainties in this mode is briefly reviewed, and some of the analyses in the literature are critically reassessed. The global picture provided by the global fit points to a coherent pattern of deviations with a significance substantially above 4$sigma$ for different New Physics scenarios. Finally, we propose as the next step in the field to focus on the study of optimized observables that compare electron and muon modes, sensitive to lepton-flavour universality violations and free from hadronic uncertainties (including charm) in the SM, the so called $Q_i$ observables.



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