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Constraints on New Physics from $B$ mesons

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 Added by Monika Blanke
 Publication date 2019
  fields
and research's language is English
 Authors Monika Blanke




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These proceedings review the status of New Physics contributions to flavour violating $B$ decays. The anomalies in charged and neutral current $B$ decays related to lepton flavour universality violation have received a substantial amount of attention over the past years, and we discuss the current status in light of the new data presented earlier this year. We also recall a tension in the neutral $B$ meson mixing observables $Delta M_d$ and $Delta M_s$ and in particular their ratio, when compared with their SM predictions obtained using tree-level determinations of the CKM matrix and the recent lattice QCD results for the relevant hadronic matrix elements. Last but not least, we advocate kaon physics as a unique probe of very high energy scales and briefly discuss the current status of $varepsilon/varepsilon$ and $Ktopi ubar u$.



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