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On The pp->ppη(eta') Reactions Near Threshold

E. Gedalin·A. Moalem·L. Razdolskaja
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Abstract

The production rate for η' in pp ->pp η' at rest is calculated in a covariant one boson exchange model, previously applied to study pi^0 and ηproduction in NN collisions. The transition amplitudes for the elementary BN -> eta' N processes with B being the meson exchanged (B = pi, sigma, eta, rho, omega and delta) are taken to be the sum of s and u channels with a nucleon in the intermediate states, and a delta meson pole in a t-channel. The couplings of the eta' to hadrons are a factor 0.437 weaker than the respective eta-hadron couplings, as suggested by a quark model and a singlet-octetmixing angle theta = -23 degree. The model reproduces near threshold cross sections for the quasielastic processes pi- p ->n eta (eta') and pp -> pp eta (eta') reactions.

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E. Gedalin, A. Moalem, L. Razdolskaja. 1998-12-02. On The pp->ppη(eta') Reactions Near Threshold. https://doi.org/10.1016/s0375-9474(99)00110-4

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