Tau Radiative Decays in the Light Front Quark Model

Abstract

We study the decays of $τ^- \to ν_τ P^-γ(P=π^-, K^-)$ 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 $1.62\times 10^{-2} (3.86\times10^{-3}) Γ_{τ^- \to ν_τ π^-}$ and $1.91\times 10^{-3} (5.38\times 10^{-4}) Γ_{τ^- \to ν_τ K^-}$ with the cuts of $E_γ=50 (400)$ MeV and $t_{0}=800 (1200)$ MeV for $τ^- \to ν_τ π^- γ$ and $τ^- \to ν_τ K^- γ$, respectively. We also show that with including the radiative decay widths, the experimental rate for $τ^-\to ν_τP^-$ can be explained.