Measurement and partial-wave analysis of the reactionK−p→KS0π+π−nat 6 GeV/c

We have performed a partial-wave analysis of the reaction $K^{-}p\to K_S^0{\pi }^{+}{\pi }^{-}n$ at 6 GeV/c. We present the results of the analysis of about 4500 events in the low-$t$ region ($\left|t^{\prime }\right|<\mathrm{}0.2\mathrm{}$ Ge${\mathrm{V}}^2$) for the dominant waves in the 1200-to-2000-MeV mass range. We observe the $2^{+}$ $K^{*}\mathrm{}\left(1430\right)\mathrm{}$ and clear signals for the $1^{+}$ $Q_2\mathrm{}\left(1400\right)\mathrm{}$ and the $3^{-}$ $K^{*}\mathrm{}\left(1800\right)\mathrm{}$. We find a new $1^{-}$ resonance at about 1500 MeV and have some evidence for another $1^{-}$ resonance at 1800 MeV. We also present the results of a partial-wave analysis as a function of $t$ in the 1430-MeV mass region.