Speaker
Description
The radiative tau decay ($\tau^- \rightarrow \pi^- \nu_\tau \gamma$) involves two contributions: the Internal Bremmstrahlung (IB) contribution and the Structure dependent (SD) contribution. The SD contribution encodes the non-perturbative QCD effects and depends on two form factors ($F_A$ and $F_V$). Here, I will discuss the computation of these form factors in the framework of light cone sum rules. The momentum transferred square, $t$ in this system is positive and can take values upto $m_\tau^2$, which makes it phenomenologically rich. We have found the structure dependent parameter, $\gamma$, (i.e. $\frac{F_A}{F_V}$ at zero momentum transfer) in good agreement with the experimental determination and also present the decay width and invariant mass spectrum in the $\pi-\gamma$ system.