Remarks on the Standard Model predictions for $R(D)$ and $R(D^{\ast })$

C. S. Kim, G. Lopez-Castro, S. L. Tostado +1

Semileptonic $b\to c$ transitions, and in particular the ratios $R(D^{(\ast )})=\frac{\Gamma (B\to D^{(\ast )}\tau \nu )}{\Gamma (B\to D^{(\ast )}\ell \nu )}$, can be used to test the univers…