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

TL;DR

This paper reports the discovery and measurement of several five-body decay modes of charmed mesons involving $K_S^0$, providing new insights into their decay patterns and resonant substructures.

Contribution

The study presents the first observation of the decay mode $D_s^+ o K_S^0 K_S^0 ho^+ o K_S^0 K_S^0 ext{(pion)} ext{(pion)}$, along with measurements of branching ratios and an analysis of resonant substructure.

Findings

Discovery of $D_s^+ o K_S^0 K_S^0 ext{(pion)} ext{(pion)}$ decay mode.

Branching ratio measurements for several five-body decay modes.

Analysis of resonant substructure in $D^0 o K_S^0 ext{(pion)} ext{(pion)} ext{(pion)} ext{(pion)}$.

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 $D_s^+\to K_S^0 K_S^0\pi^+\pi^+\pi^-$. The branching ratio for the new mode is {${\Gamma(D_s^+\to K_S^0K_S^0\pi^+\pi^-\pi^+)} \over {\Gamma(D_s^+\to K_S^0K^-\pi^+\pi^+)}$} = 0.102$\pm0.029\pm$0.029. We also determine the branching ratio of {${\Gamma(D^0\to K_S^0\pi^+\pi^+\pi^-\pi^-)} \over {\Gamma(D^0 \to K_S^0\pi^+\pi^-)}$} = 0.095$\pm0.005\pm$0.007 as well as an upper limit for {${\Gamma(D^0\to K_S^0K^-\pi^+\pi^+\pi^-)} \over {\Gamma(D^0\to K_S^0\pi^+\pi^+\pi^-\pi^-)}$} $<$ 0.054 (90% CL). An analysis of the resonant substructure for $D^0 \to K_S^0\pi^+\pi^+\pi^-\pi^-$ is also performed.