Study of Hadronic Five-Body Decays of Charmed Mesons Involving $K_S^0$

Abstract

We study the decay of $D^0$ and $D^+_s$ mesons into five-body final states including a $K_S^0$ and report the discovery of the decay mode $D_s^+\to K_S^0 K_S^0π^+π^+π^-$. The branching ratio for the new mode is {${Γ(D_s^+\to K_S^0K_S^0π^+π^-π^+)} \over {Γ(D_s^+\to K_S^0K^-π^+π^+)}$} = 0.102$\pm0.029\pm$0.029. We also determine the branching ratio of {${Γ(D^0\to K_S^0π^+π^+π^-π^-)} \over {Γ(D^0 \to K_S^0π^+π^-)}$} = 0.095$\pm0.005\pm$0.007 as well as an upper limit for {${Γ(D^0\to K_S^0K^-π^+π^+π^-)} \over {Γ(D^0\to K_S^0π^+π^+π^-π^-)}$} $<$ 0.054 (90% CL). An analysis of the resonant substructure for $D^0 \to K_S^0π^+π^+π^-π^-$ is also performed.