$\phi$ and $\omega$ meson production in $\mathrm{pp}$ reactions at $p_{\mathrm{lab}}=3.67\mathrm{}\hspace{0.5em}\mathrm{GeV}/c$

The exclusive production cross sections for $\omega$ and $\phi$ mesons have been measured in proton-proton reactions at $p_{\mathrm{lab}}=3.67\mathrm{}\hspace{0.5em}\mathrm{GeV}/c.\mathrm{}$ The observed $\phi /\omega$ cross section ratio is $(3.8\mathrm{}\pm {0.2}_{-0.9}^{+1.2\mathrm{}})\times {10}^{-3}.$ After phase space corrections, this ratio is enhanced by about an order of magnitude relative to naive predictions based upon the Okubo-Zweig-Iizuka (OZI) rule, in comparison to an enhancement by a factor $\sim 3$ previously observed at higher beam momenta. The modest increase of this enhancement near the production threshold is compared to the much larger increase of the $\phi /\omega$ ratio observed in specific channels of $\overline{p}p$ annihilation experiments. Furthermore, differential cross section results are also presented which indicate that although the $\phi$ meson is predominantly produced from a ${}^3{P}_1$ proton-proton entrance channel, other partial waves contribute significantly to the production mechanism at this beam momentum.