Hyperon Production at the COSY-11 Facility


Kaon-hyperon production in proton-proton scattering has been studied in the pp->pK+Lambda/Sigma0 reaction channels close to threshold. At equal excess energies (Q ~ 13 MeV), Lambda production is found to be favoured over Sigma0 production by a factor 28 (+6,-9) and thus exceeding the known high energy (Q > 300 MeV) ratio by an order of magnitude.
Experiments were performed using the internal COSY-11 facility at the cooler synchrotron COSY Jülich. Results are presented and physics implications for the underlying reaction mechanisms are discussed.

Complete document in PostScript format (~420kB)
Publication: Proceedings 'Hadrons in Dense Matter', GSI Darmstadt, ISSN 0720-8715, p. 27-34