Tau Radiative Decays in the Light Front Quark Model

Abstract

We study the decays of $\tau^- \to \nu_{\tau} P^-\gamma (P=\pi^-, K^-)$ in the light front quark model. We calculate the form factors and use them to evaluate the decay widths. We find that, in the standard model, the decay widths are $1.62\times 10^{-2} (3.86\times10^{-3}) \Gamma_{\tau^- \to \nu_{\tau} \pi^-}$ and $1.91\times 10^{-3} (5.38\times 10^{-4}) \Gamma_{\tau^- \to \nu_{\tau} K^-}$ with the cuts of $E_{\gamma}=50 (400)$ MeV and $t_{0}=800 (1200)$ MeV for $\tau^- \to \nu_{\tau} \pi^- \gamma$ and $\tau^- \to \nu_{\tau} K^- \gamma$, respectively. We also show that with including the radiative decay widths, the experimental rate for $\tau^-\to \nu_\tau P^-$ can be explained.