The production of the Lambda and Sigma0
hyperons has been measured via the
pp->pK+Lambda / Sigma0
reaction at the internal COSY-11 facility in the excess energy
range between 14 and 60 MeV.
The transition of the Lambda / Sigma0
cross section ratio from about 28 at Q <= 13 MeV
to the high energy level of about 2.5 is covered by the data
showing a strong decrease of the ratio between 10 and 20 MeV
excess energy.
The strength of the final state interactions in the
p-Sigma0 channel seems to be much smaller
compared to the p-Lambda one.
Estimates of the effective range parameters are given for the
N Lambda and the N Sigma0
systems.
Preprint in
PostScript format (415kB)
E-print:
http://xxx.lanl.gov/abs/nucl-ex/0402008
Eur.Phys.Jou. A
22
(2004)
293-299