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

TL;DR

This paper explores potential new physics effects in specific B meson decays involving tau leptons, using a model-independent approach and form factor calculations to constrain and analyze these effects.

Contribution

It introduces a comprehensive framework combining effective Hamiltonian analysis with covariant quark model form factors to study new physics in B decays.

Findings

Constraints on NP scenarios derived from experimental data

Predictions for observables sensitive to NP effects

Enhanced understanding of form factors across the full kinematic range

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.