LCSR application to radiative tau decay
A. Bansal* and N. Mahajan
Pre-published on:
October 25, 2021
Published on:
November 17, 2021
Abstract
The non-perturbative QCD effects involved in radiative tau decay ($\tau^- \rightarrow \pi^- \nu_\tau \gamma$) are encoded in two form factors (FFs); vector ($F_V$) and axial-vector ($F_A$). These FFs are the same as those involved in radiative pion decay with the crucial difference that the square of the momentum transferred, $t$, between the $\pi-\gamma$ system is positive. This makes them timelike and can result in the production of real hadronic resonances. We calculate the analytical form for these FFs using the method of light-cone sum rules (LCSR) and present the decay width and the invariant mass spectrum of the $\pi-\gamma$ system. The structure-dependent parameter $\gamma$ (i.e., $\frac{F_A}{F_V}$ at zero momentum transfer) is found to be in good agreement with the experimental determination.
DOI: https://doi.org/10.22323/1.397.0193
How to cite
Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating
very compact bibliographies which can be beneficial to authors and
readers, and in "proceeding" format
which is more detailed and complete.