Antiproton Annihilation in Hydrogen at Rest. I. Reactionp¯+p→K+K¯+π

In a study of 735 000 antiproton annihilations at rest in the hydrogen bubble chamber, 182 examples of the reaction $K_1{K}_1{\pi }^0$ and 851 examples of the reaction $K_1{K}^{\pm }{\pi }^{\mp }$ were recorded. The distributions in the internal variables of these reactions are presented. A substantial fraction of the latter reaction proceeds through an intermediate $K^{*}$ state; $\overline{p}+p\to K+K^{*}$. The theory of the interference effects in this reaction is presented and compared with the experimental result. It is concluded that the $K{K}^{*}$ annihilation proceeds dominantly from the ${}_{}{}^3{}_{}{}^{}S$, $I=1\mathrm{}$ state of the $\overline{N}N$ system. The fraction of $\overline{p}p$ annihilations into $K{K}^{*}$ is given as $f_{K{K}^{*}}=(2.1\mathrm{}\pm 0.3)\times {10}^{-3\mathrm{}}$.