A partial wave analysis of the decay $D^0 \to K_S^0 \pi^+\pi^−$

13 pp. (1993).
Using the ARGUS detector at the DORIS-II electron-positron storage ring at DESY, we have investigated the exclusive decay $D∗+→ D^0 π^+, D^0→ K_S^0 π^+π^−$. From a partial wave analysis of the $K_S^0 π+^π^−$ system we find that (71.8± 4.2 ± 3.0)% are $D^0→ K∗^−π^+$ and (22.7 ± 3.2 ± 0.9)% are $D^0→K^0_ϱ 0$ with a relative phase of (−137 ± 7 ± 3)° between the channels. The remaining fraction can be described by several channels involving excited resonances, but not by a three-body phase space decay, thus giving first evidence for D0 decays into $K^0_∗(1430)^−π^+,K^0f^0(1975), K^0f^2(1270), and K^0f^0(1400)$.