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Near threshold eta production in proton-proton collisions

M. Batinic·A. Svarc·T. -S. H. Lee
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Abstract

The total cross section for the near threshold eta production in proton-proton collisions has been investigated with the assumption that the production mechanism is due to the emission of a meson x (pi, eta, sigma) from one of the nucleons followed by a x N --> eta N transition on the second one. The x N --> eta N amplitudes are generated from the unitary multi-channel multi-resonance model which has recently been constructed in analyzing the pi N scattering and pi N --> eta N reaction. The initial and final pp distortions are calculated from a coupled-channel pi-NN model which describes the NN scattering data up to about 2 GeV. With the x-NN vertex functions taken from the Bonn potential, the predicted total cross sections of threshold pp --> eta pp reaction are in good agreement with the data. In contrast to previous works, we find that the eta-exchange plays an important role. The effect of the two-pion exchange, simulated by sigma- exchange, is found to be significant but not as dominant as the vector meson-exchange introduced in previous works.

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M. Batinic, A. Svarc, T. -S. H. Lee. 1996-04-25. Near threshold eta production in proton-proton collisions. https://doi.org/10.1088/0031-8949%2F56%2F4%2F001

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