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 $1.62\times 10^{-2}(3.86\times 10^{-3}){\Gamma }_{{\tau }^{-}\to {\nu }_{\tau }{\pi }^{-}}$ 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.

Comments: 17 pages, 4 Figures, to be published in Phys. Rev. D