A possible arena for searching new physics – the Γ(D0→ρ0γ)/Γ(D0→ωγ) ratio

We propose to investigate flavour changing neutral currents in the c→uγ transition through the measurement of the difference between Γ(D0→ρ0γ) and Γ(D0→ωγ). This is based on the observation that D0→(dd̄)γ is due to long distance physics while D0→(uū)γ arises from the c→uγ transition. The effect of ρ−ω mixing is included. A difference in the decay widths of more than about 30 % would be indicative of new physics.