Production of the omega-Meson at Threshold in the reaction pp->pp omega at COSY-11


In various meson exchange models the heavier mesons like the omega(783)-, the sigma-, the correlated 2 pi, and the rho-meson are important as exchange mesons in short range baryon-baryon interaction. The on shell production of these heavier mesons will yield valuable information concerning the coupling constants. Apart from the sigma which is not a genuine particle the omega and the rho are accessible in p p interactions. Due to the small solid angle at the COSY-11 installation only the width of the omega (from these two mesons) is sufficiently small to perform successfully threshold production measurements at the COSY-11 installation. The production rate of both, the omega(783) and the phi(1020)-meson are important to probe the - perhaps OZI-violating - ratio of the phi to omega production. Measurements close to the production threshold allow the examination of the reaction mechanism and the meson-nucleon final state interaction to determine for instance the meson-nucleon coupling constant. It is proposed to measure the omega production via the pp->pp omega reaction at a beam momentum of 2.74 GeV/c, sufficiently above the omega mass to cover the whole omega width.

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