New physics and the tau polarization vector in b → cτ −ν¯τ decays


  • Neus Penalva IFIC (CSIC-UV)
  • Juan Nieves IFIC (CSIC-UV)
  • Eliecer Hernández U.Salamanca



Beyond the Standard Model, CP violation, Lepton Flavour Universality


For a general H_b→H_c τ ν_τ decay, we analyze the role of theτpolarization vector P^μ in the context of lepton flavor universality violation studies. We use a general phenomenological approach that includes several new physics terms and we make specific evaluations of P^μ fordifferent decays. We show that a P^μ component orthogonal to the plane determined by the final hadron and τ three-momenta is only possiblefor complex Wilson coefficients and it would be associated to a violation of the CP symmetry.


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How to Cite

Penalva N, Nieves J, Hernández E. New physics and the tau polarization vector in b → cτ −ν¯τ decays. Supl. Rev. Mex. Fis. [Internet]. 2022 Jun. 13 [cited 2022 Dec. 9];3(3):0308058 1-5. Available from: