Neutral-strange-particle production in antiproton-proton reactions at 3.0 GeV/c

The reactions $\overline{p}p\to V^0+\mathrm{neutrals}$ were studied in a multiparticle spectrometer at 3.0 GeV/c incident momentum, with a sensitivity of about 150 events/μb. Differential cross sections and polarization of the $\overline{\Lambda }$ for the final states $\overline{\Lambda }\left(\Lambda \right)$ and $\overline{\Lambda }\left({\Sigma }^0\right)$ are reported and compared with theoretical models. Differential cross sections of the $K^0$ in $K^0\left[K^{*}\mathrm{}\right(890\left)\right]$ and the $\Lambda$ in $\Lambda (\overline{\Lambda }+{\overline{\Sigma }}^0)$ are also measured. Upper limits of a few $\mu \mathrm{b}$ MeV are obtained for the formation of narrow resonances decaying into $V^0+\mathrm{neutrals}$ in the mass interval 2.74-2.80 ${\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c}}^2$.