$\ddot{I}•$ and $\ddot{I}‰$ Meson Production in pp Reactions at $p_{lab}$=3.67 GeV/c

Abstract

The exclusive production cross sections for $\ddot{I}‰$ and $\ddot{I}•$ mesons have been measured in proton-proton reactions at $p_{lab}=3.67$ GeV/c. The observed $\ddot{I}•/\ddot{I}‰$ cross section ratio is $(3.8\pm 0.2_{-0.9}^{+1.2})\times 10^{-3}$. 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 $\ddot{I}•/\ddot{I}‰$ ratio observed in specific channels of $\bar{p}p$ annihilation experiments. Furthermore, differential cross section results are also presented which indicate that although the $\ddot{I}•$ 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.

Revtex 49 pages, 11 figures, Phys Rev C in print