A study of D0→KS0KS0X decay channels

Using data from the FOCUS experiment (FNAL-E831), we report on the decay of D0 mesons into final states containing more than one KS0. We present evidence for two Cabibbo favored decay modes, D0→KS0KS0K−π+ and D0→KS0KS0K+π−, and measure their combined branching fraction relative to D0→K¯0π+π− to be Γ(D0→KS0KS0K±π∓)Γ(D0→K¯0π+π−)=0.0106±0.0019±0.0010. Further, we report new measurements of Γ(D0→KS0KS0KS0)Γ(D0→K¯0π+π−)=0.0179±0.0027±0.0026, Γ(D0→K0K¯0)Γ(D0→K¯0π+π−)=0.0144±0.0032±0.0016, and Γ(D0→KS0KS0π+π−)Γ(D0→K¯0π+π−)=0.0208±0.0035±0.0021 where the first error is statistical and the second is systematic.