1302.7031 (Murugeswaran Duraisamy et al.)

The Full $B \to D^{*} τ^{-} \bar{ν_τ}$ Angular Distribution and
CP violating Triple Products    [PDF]

Murugeswaran Duraisamy, Alakabha Datta

We perform a comprehensive study of the impact of new-physics operators with different Lorentz structures on $\bar{B} -> D^{*} l^- \bar{\nu}_l$ decays, $\ell = e^-, \mu^-, \tau^- $, involving the $b \to c l \nu_\ell$ transition. We present the full three angle and $q^2$ angular distribution with new physics operators with complex couplings. Various observables are constructed from the angular distribution and we specially focus on the CP violating triple product asymmetries which vanish in the Standard Model without any hadronic complications. Two of the three triple products are only sensitive to vector/axial vector new physics and do not depend on pseudoscalar new physics. Hence the measurements of non zero triple product asymmetries will be clear sign of new physics and strong signals for vector/axial vector new physics operators. Even though we focus on $\tau$ final state, one can use the triple products to search for new physics with $e$ and $\mu$ in the final state.

View original: http://arxiv.org/abs/1302.7031