$D^{\ast }$ Polarization as an Additional Constraint on New Physics in the $b\to c\tau {\bar{\nu }}_{\tau }$ Transition

Mikhail A. Ivanov, Jürgen G. Körner, Pietro Santorelli +1

Measurements of the branching fractions of the semileptonic decays $B\to D^{(\ast )}\tau {\bar{\nu }}_{\tau }$ and $B_c\to J/\psi \tau {\bar{\nu }}_{\tau }$ systematically exceed the Standard Model (SM) predictions, pointi…