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