A measurement of the Cabibbo-suppressed decays D0 → π−π+ and D0 → K−K+

Abstract

We report a measurement of the relative branching ratio of two Cabibbo-suppressed decay modes: D 0 → π − π + and D 0 → K − K +. The data were accumulated in the 1990–1991 fixed target run of Fermilab high energy photoproduction experiment E687. The branching ratios of these modes relative to the Cabibbo-allowed decay D 0 → K − π + are also presented. The relative branching ratios are measured to be Γ( D 0 → KK)/ Γ( D 0 → ππ) = 2.53 ± 0.46 ± 0.19, Γ( D 0 → KK)/ Γ( D 0 → Kπ) = 0.109 ± 0.007 ± 0.009, and Γ( D 0 → ππ)/ Γ( D 0 → Kπ) = 0.043 ± 0.007 ± 0.003.