ReactionK−p→Ληfrom 1.2 to 1.7BeVc

Total and differential cross sections of the reaction $K^{-}p\to \Lambda \eta$ have been determined for incident $K^{-}$ lab momenta between 1.2 and 1.7 $\frac{\mathrm{BeV}}{c}$. No striking resonance formation in the direct channel is seen; in particular, the $Y_0^{}{}_{}{}^{*}\mathrm{}\left(2100\right)\mathrm{}$ decays not more than 3% via the $\Lambda \eta$ channel. A prominent forward peak in the differential cross sections indicates some crossed-channel meson-exchange activity. The branching ratio $\frac{\Gamma (\eta \to \mathrm{neutrals})}{\Gamma (\eta \to {\pi }^{+}{\pi }^{-}{\pi }^0)} \mathrm{is} 3.6\pm 0.6$.