Search for Lepton Flavor Non-universality with B→ (K, K*) τ+τ- Decays

  • P. MajiEmail author
  • S. Biswas
  • P. Nayek
  • S. SahooEmail author


The decay modes of B meson consisting tau leptons as final state particle are seemed to be the key feature for searching new physics. As the experimental measurements for b → +τ processes are still not confirmed, the theoretical study of these decays is playing vital role in recent times. The lepton flavor universality violation gains much curiosity after the observation of RK and \( {R}_{K^{\ast }} \) anomalies in semileptonic \( B\to \left(K,{K}^{\ast}\right)\mu \overline{\mu} \) channel which provides a hint towards μ − e non-universality in flavor sector. In this paper, we have devoted our concern to the decay mode B → (K, K)τ+τ to predict the branching ratio. We have also searched for the τ − l (where l = e, μ) lepton flavor non-universality for neutral current transitions. We have estimated our results in the standard model as well as in Z′ model.


B meson decays Lepton flavor non-universality Standard model Z′ model 



P. Maji acknowledges the DST, Govt. of India for providing INSPIRE Fellowship through IF160115 for her research work. P. Nayek and S. Sahoo would like to thank SERB, DST, Govt. of India for financial support through grant no. EMR/2015/000817. S. Sahoo also acknowledges the financial support of NIT Durgapur through “Research Initiation Grant” office order No. NITD/Regis/OR/25 dated 31st March, 2014 and NITD/Regis/OR/2014 dated 12th August, 2014. S. Biswas also acknowledges NIT Durgapur for providing fellowship for her research.


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Authors and Affiliations

  1. 1.Department of PhysicsNational Institute of Technology DurgapurDurgapurIndia

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