Resolving $R_D$ and $R_{D^{\ast }}$ anomalies

Abstract

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

arXiv comment4 pages, 2 figures, Contribution to proceedings of 16th Conference on Flavor Physics and CP Violation (FPCP 2018), July 14-18, 2018, Hyderabad, India

References in corpus (8)

• Testing leptoquark models in $\bar{B}\to D^{(\ast )}\tau \bar{\nu }$
• Measurement of the ratio of branching fractions $\mathcal{B}(B_c^{+}\to J/\psi {\tau }^{+}{\nu }_{\tau })$/$\mathcal{B}(B_c^{+}\to J/\psi {\mu }^{+}{\nu }_{\mu })$
• Flavor models for $\bar{B}\to D^{(\ast )}\tau \bar{\nu }$
• New physics solutions for $R_D$ and $R_{D^{\ast }}$
• New Physics in b -> s mu+ mu-: CP-Conserving Observables
• D* polarization as a probe to discriminate new physics in B --> D* tau nubar
• The Azimuthal $B\to D^{\ast }{\tau }^{-}\overline{{\nu }_{\tau }}$ Angular Distribution with Tensor Operators
• Resolution of $R_D$/$R_{D^{\ast }}$ puzzle

Cited by in corpus (1)

• New Physics solutions for $b\to c\tau \bar{\nu }$ anomalies after Moriond 2019