engleski

Near threshold eta production in proton-proton collisions

The total cross sections 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 chi(pi eta sigma from one of the nucleons followed by a chi N --> eta N transition on the second nucleon. The chi N --> eta N amplitudes are generated from the unitary multi-channel multiresonance model which has recently been constructed by fitting the data of pi N elastic 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 chi 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.

nucleon nucleon collision ; spp->pp-eta reaction ; meson production ; near-threshold ; scattering ; model

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