Study ofωproduction near threshold in the reactionπ−p→ωn

We have investigated $\omega$ production in the reaction ${\pi }^{-}p\to \omega n$ very close to threshold. The dependence of the mass, width, branching ratio, and cross section upon the final-state c.m. momentum, $P^{*}$, were studied. The mass and width were independent of $P^{*}$ with values of 782.4 ± 0.5 and 10.22 ± 0.43 MeV, respectively. The branching ratio $\frac{\Gamma (\omega \to {\pi }^0\gamma )}{\Gamma (\omega \to {\pi }^{+}{\pi }^{-}{\pi }^0)}$ was also constant, having a value of 0.084 ± 0.013. An upper limit of 0.18 was set on the branching ratio $\frac{\Gamma (\omega \to {\pi }^0{\pi }^0\gamma )}{\Gamma (\omega \to {\pi }^0\gamma )}$. We observed a rapid fall in the cross section below $P^{*}=100\mathrm{}$ MeV/c. This could not be explained in terms of $S$-wave production alone, but could be fitted by a resonant $P$ wave plus a noninterfering $S$ wave.