A closer look at the $R_D$ and $R_{D^*}$ anomalies

par Diptimoy Ghosh (Weizmann Institute)

jeudi 20 oct. 2016, 11:00 → 12:30 Europe/Paris

Auditorium (Annecy-le-Vieux)

The measurement of $R_D$ ($R_{D^*}$), the ratio of the branching fraction of $\overline{B} \to D \tau \bar{\nu}_\tau (\overline{B} \to D^* \tau \bar{\nu}_\tau)$ to that of $\overline{B} \to D l \bar{\nu}_l (\overline{B} \to D^* l \bar{\nu}_l)$, shows $1.9 \sigma$ $(3.3 \sigma)$ deviation from its Standard Model (SM) prediction. The combined deviation is at the level of $4 \sigma$ according to the Heavy Flavour Averaging Group. In this talk, I will discuss an effective field theory analysis (at the dimension-6 level) of these potential New Physics signals and ways to distinguish the various possible explanations.