Measurement of an excess of B̄→D(*) τ-ν̄τ decays and implications for charged Higgs bosons

@article{Lees2013MeasurementOA,
  title={Measurement of an excess of B̄→D(*) $\tau$-$\nu$̄$\tau$ decays and implications for charged Higgs bosons},
  author={The Babar Collaboration J. P. Lees and Others},
  journal={Physical Review D},
  year={2013},
  volume={88},
  pages={072012}
}
Based on the full BABAR data sample, we report improved measurements of the ratios R(D)=B(B→Dτ-ντ)/ B(B→Dl-νl) and R(D*)=B(B→D*τ-ντ)/ B(B→D*l-νl), where l refers to either an electron or muon. These ratios are sensitive to new physics contributions in the form of a charged Higgs boson. We measure R(D)=0.440±0.058±0.042 and R(D*)=0.332±0. 024±0.018, which exceed the standard model expectations by 2.0σ and 2.7σ, respectively. Taken together, the results disagree with these expectations at the 3.4… Expand
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