Study of Radiative Leptonic D Meson Decays

Abstract

We study the radiative leptonic $D$ meson decays of $D^+_{(s)}\to ł^+ν_łγ$ ($ł=e,μ,τ$), $D^0\to ν\barνγ$ and $D^0\to ł^+ł^-γ$ ($l=e,μ$) within the light front quark model. In the standard model, we find that the decay branching ratios of $D^+_{(s)}\to e^+ν_eγ$, $D^+_{(s)}\toμ^+ν_μγ$ and $D^+_{(s)}\toτ^+ν_τγ$ are $6.9\times 10^{-6}$ ($7.7\times 10^{-5}$), $2.5\times 10^{-5}$ ($2.6\times 10^{-4}$), and $6.0\times 10^{-6}$ ($3.2\times 10^{-4}$), and that of $D^0\toł^+ł^-γ$ ($ł=e,μ$) and $D^0\toν\barνγ$ are $6.3\times 10^{-11}$ and $2.7\times 10^{-16}$, respectively.