ReactionK−p→Λωfrom 1.2 to 2.7BeVc: The Absorption Model with Strange-Meson Exchange

Abstract

We have analyzed over 9000 $K^{-}p\to \Lambda \omega \to \left(p{\pi }^{-}\right)\left({\pi }^{+}{\pi }^{-}{\pi }^0\right)$ events in four momentum regions between 1.2 and 2.7 $\frac{\mathrm{BeV}}{c}$. We have systematically determined the differential cross section and the 11 independent decay-correlation parameters as a function of production angle for each of the four momentum regions. A striking forward peak in the differential cross section at our highest momentum, 2.6 $\frac{\mathrm{BeV}}{c}$, suggests the appearance of strange-meson exchange. Using a new formalism for the absorption model, we show that the behavior of the differential cross section and the decay-correlation parameters at 2.6 $\frac{\mathrm{BeV}}{c}$ as a function of production angle is qualitatively explained by the absorption model with $K$ and $K^{*}$ exchange. Using available data on $K^{-}p\to \Lambda \phi$ at 2.6 $\frac{\mathrm{BeV}}{c}$, we show that the absorption model also explains the behavior of $K^{-}p\to \Lambda \phi$, and that the comparison between the couplings of $K^{-}p\to \Lambda \omega$ and $K^{-}p\to \Lambda \phi$ is in reasonable agreement with $\mathrm{SU}\left(3\right)\mathrm{}$ predictions.