Study of hadronic five-body decays of charmed mesons involving K0

We study the decay of D0 and D+s mesons into five-body final states including a KS0 and report the discovery of the decay mode Ds+→K S0KS0π+π +π-. The branching ratio for the new mode is Γ(Ds+→KS0K S0π+π-π+) Γ(Ds+→KS0K -π+π+)=0.102±0.029±0.029. We also determine the branching ratio of Γ(D0→K S0π+π+π -π-)Γ(D0→KS 0π+π-)=0.095±0.005±0.007 as well as an upper limit for Γ(D0→KS 0K-π+π+π-) Γ(D0→KS0π+π +π-π-)<0.054 (90% CL). An analysis of the resonant substructure for D0→KS 0π+π+π-π- is also performed.