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Omega- and Phi-meson production in pn -> dV reactions and OZI-rule violation

L. A. Kondratyuk·Ye. S. Golubeva·M. Buescher
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Abstract

We investigate the reactions p n -> d omega and p n -> d phi close to threshold and at higher energies. Near threshold we calculate the S-wave amplitudes within the framework of the two-step model which is described by a triangle graph with pi-mesons in the intermediate state and find a ratio of the S-wave amplitudes squared of R =|A(phi)|^2/|A(omega)|^2 = (4-8) x 10^{-3}. Any significant enhancement of the experimental value of R(phi/omega) over this prediction can be interpreted as a possible contribution of the intrinsic s - anti s component in the nucleon-wave function. We present arguments that there is a strong resonance effect in the omega N channel close to threshold. At higher energies we calculate the differential cross sections of the reactions p n -> d omega, p n -> d phi and the ratio of the phi/omega yields within the framework of the quark-gluon string model. An irregular behavior of the phi/omega-ratio is found at s <= 12 GeV^2 due to the interference of the t- and u-channel contributions.

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L. A. Kondratyuk, Ye. S. Golubeva, M. Buescher. 1998-08-18. Omega- and Phi-meson production in pn -> dV reactions and OZI-rule violation. https://arxiv.org/abs/nucl-th/9808050

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