Analyzing New Physics in $\bar{B}^0 \to D^{(\ast)}\tau^-\bar\nu_{\tau}$

Abstract

We discuss possible new physics (NP) effects beyond the standard model (SM) in the exclusive decays $\bar{B}^0 \to D^{(\ast)} \tau^- \bar{\nu}_{\tau}$. Starting with a model-independent effective Hamiltonian including non-SM four-Fermi operators, we show how to obtain experimental constraints on different NP scenarios and investigate their effects on a large set of physical observables. The $\bar{B}^0 \to D^{(\ast)}$ transition form factors are calculated in the full kinematic $q^2$ range by employing the covariant confined quark model developed by our group.