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A theoretical study of the nuclear reaction cross-section for the production of 64Cu and 86Y was performed from the nuclear reactions 64Ni(p, n) 64Cu, 64Ni(d, 2n) 64Cu, 66Zn(d, α)64Cu, 68Zn(p, n α)64Cu, 86Sr(p, n) 86gY, 87Sr(p, 2n) 86gY and 88Sr(p, 3n) 86gY. The calculations were performed using three codes EMPIRE, TALYS and ALICE-IPPE. The excitation function curves for the investigated reactions have been constructed from the enriched targets using 64Ni, 66Zn, 68Zn, 86Sr, 87Sr and 88Sr. The calculated excitation functions and the experimental data were compared. Mean standardized deviation, mean relative deviation and mean ratio statistical parameters were introduced to control the quality of the fitting between both the experimentally and the theoretically calculated cross-sections.

The production of eta mesons has been measured in the proton-proton interaction close to the reaction threshold using the COSY-11 internal facility at the cooler synchrotron COSY. Total cross sections were determined for eight different excess energies in the range from 0.5 MeV to 5.4 MeV. The energy dependence of the total cross section is well described by the available phase-space volume weighted by FSI factors for the proton-proton and proton-eta pairs., Comment: 9 pages, 1 table, 5 figures

Threshold measurements of the associated strangeness production reactions pp --> pK(+)Lambda and pp --> pK(+)Sigma(0) are presented. The most remarkable feature of the data is that at the same excess energy the total cross section for the Sigma(0) production appears to be about a factor of 28(-9)(+6) smaller than for the Lambda particle. It is concluded that strong Sigma(0)p final state interactions, and in particular the Sigma N --> Lambda p conversion reaction, are the likely cause of the depletion in the Sigma signal. This hypothesis is in line with other experimental evidence in the literature.

The $pp \to pp \eta^{\prime}$ (958) reaction has been measured at COSY using the internal beam and the COSY-11 facility. The total cross sections at the four different excess energies \mbox{$ Q = ~1.5 ~MeV, ~1.7 ~MeV, ~2.9 ~MeV,$ and $ ~4.1 MeV$} have been evaluated to be \mbox{$ \sigma = 2.5 \pm 0.5~nb$, $~~~ 2.9 \pm 1.1~nb$, $~~~ 12.7 \pm 3.2~nb$, ~ and $~~~ 25.2 \pm 3.6 ~nb $}, respectively. In this region of excess energy the $\eta^{\prime}$ (958) cross sections are much lower compared to those of the $\pi ^0$ and $\eta$ production.

The energy dependence of the total cross section for the pp \to pK^+\Lambda reaction was measured in the threshold region covering the excess energy range up to 7MeV. Existing model calculations describe the slope of the measured cross sections well, but are too low by a factor of two to three in rate. The data were used for a precise determination of the beam momentum of the COSY-synchrotron.

The pp → pK+Λ reaction was measured at COSY with a proton beam momentum of 2.345 GeV/c, i.e. with an excess energy of 2 MeV above threshold. The total cross section was determined to be 8.2 ± 1.8 nb. The present data point close to the production threshold indicates, that existing phenomenological parametrizations of the total kaon production cross section are insufficient.

The COSY-11 installation is an internal experiment at the cooler synchrotron and storage ring COSY Julich. It has been designed for full geometrical acceptance close to threshold for meson production studies, especially in the 1 GeV/c2 mass range. The experimental setup makes use of a regular C-type COSY dipole magnet, following a cluster target, to separate reaction products from the beam and to analyze their momenta, thus allowing the observation of charged reaction products at small angles with beam energies close to threshold. Resonances will be identified by missing mass reconstructions from measured four-momenta of two outgoing protons in the predominantly studied pp → ppX reaction. In addition, charged mesons either produced directly or from decays of X will be detected. The different components of the experimental facility are presented.

Close-to-threshold data on the elementary kaon and antikaon production channels in the proton-proton interaction have been taken using the COSY-11 installation at the cooler synchrotron COSY Julich. The experimental technique applied at the internal COSY-11 facility—designed for meson production studies at small excess energies—is outlined. The threshold excitation functions for the kaon-hyperon production via the reactions pp→pK+Λ and pp→pK+Σ0 are presented. The magnitude of the production amplitudes is compared at equal excess energies and physical implications of the observed Σ0 suppression in the threshold region are discussed. In addition, within a Dalitz plot analysis the spin-averaged S-wave scattering parameters could be extracted for the Λ-p channel. With the possibility of detecting all final state particles the elementary antikaon production in the reaction pp→ppK+K− has been investigated. Results on the exclusive total cross section fix the scale of the strangeness dissociation into two kaons.

The experimental setup and detection technique of the COSY-11 installation, an internal experimental facility at the cooler synchrotron and storage ring COSY Julich, are described. The detection system has been designed for meson production studies with full geometrical acceptance close to threshold. Preliminary results of first measurements are presented, emphasis is put on strangeness production in the reactions pp → ppK + K − and pp → pK + Λ .