Annihilation into Channels with Strangeness and the OZI Rule Violation

Abstract

Two-step mechanisms in the $N\bar{N}$ annihilation and their role in the OZI rule violating reactions are discussed. In particular the two meson rescattering mechanism for $\pi \varphi$ channel including all off-shell effects is typically two orders of magnitude bigger than the OZI tree level expectation and explains the observed ratio $\varphi \pi /\omega \pi$ in the annihilation at rest. The rates for the final states including photons, $\gamma \omega$ and $\gamma \varphi$, can be explained in the vector dominance model. The observed rate for $p\bar{p}\to \gamma \omega$ is suppressed due to destructive interference between the intermediate $\rho$ and $\omega$ states while the interference in $p\bar{p}\to \gamma \varphi$ is required to be constructive leading to a large ratio $\gamma \varphi /\gamma \omega$.

arXiv comment14 pages, 8 PostScript figures, Invited contribution at LEAP-96, August 1996, Dinkelsbuehl, Germany, to be published in Nucl. Phys. B Proceeding Supplement

References in corpus (2)

• Abundant phi-Meson Production in pbar-p Annihilation at Rest and Strangeness in the Nucleon
• Rates for the reactions antiproton-proton --> pi phi and gamma phi

Cited by in corpus (4)

• Proton-Antiproton Annihilation and Meson Spectroscopy with the Crystal Barrel
• $\varphi$ and $\omega$ Meson Production in pp Reactions at $p_{lab}$=3.67 GeV/c
• Photoproduction of phi mesons from the proton: Polarization observables and strangeness in the nucleon
• Radiative proton-antiproton annihilation and isospin mixing in protonium