Resolving \(R_D\) and \(R_{D^*}\) Anomalies

  • Suman KumbhakarEmail author
  • Ashutosh Kumar Alok
  • Dinesh Kumar
  • S. Uma Sankar
Conference paper
Part of the Springer Proceedings in Physics book series (SPPHY, volume 234)


The current world averages of the ratios \(R_{D^{(*)}}\) are about \(4\sigma \) away from their Standard Model prediction. These measurements indicate towards the violation of lepton flavor universality in \(b\rightarrow c\,l\,\bar{\nu }\) decay. The different new physics operators, which can explain the \(R_{D^{(*)}}\) measurements, have been identified previously. We show that a simultaneous measurement of the polarization fractions of \(\tau \) and \(D^*\) and the angular asymmetries \(A_\mathrm{FB}\) and \(A_\mathrm{LT}\) in \(B\rightarrow D^*\tau \bar{\nu }\) decay can distinguish all the new physics amplitudes and hence uniquely identify the Lorentz structure of new physics.


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Copyright information

© Springer Nature Switzerland AG 2019

Authors and Affiliations

  • Suman Kumbhakar
    • 1
    Email author
  • Ashutosh Kumar Alok
    • 2
  • Dinesh Kumar
    • 3
  • S. Uma Sankar
    • 1
  1. 1.Indian Institute of Technology BombayMumbaiIndia
  2. 2.Indian Institute of Technology JodhpurJodhpurIndia
  3. 3.University of RajasthanJaipurIndia

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