We show that the recently measured asymmetry in helicity-angle spectra of the Lambda-hyperons produced in the reaction pp -> K^+Lambda p reaction and the energy dependence of the total pp -> K^+Lambda p cross section can be explained consistently by the same Lambda p final-state interaction. Assuming that there is no final-state interaction in the Sigma^0 p channel, as suggested by the available data, we can also reproduce the energy dependence of the Lambda/Sigma^0 production ratio and, in particular, the rather large ratio observed near the reaction thresholds. The nominal ratio of the Lambda and Sigma^0 production amplitudes squared, i.e. when disregarding the final-state interaction, turns out to be about 3, which is in line with hyperon production data from proton and nuclear targets available at high energies.
@article{arxiv.hep-ph/0608098,
title = {Phenomenology of the Lambda/Sigma^0 production ratio in pp collisions},
author = {A. Sibirtsev and J. Haidenbauer and H. -W. Hammer and U. -G. Meißner},
journal= {arXiv preprint arXiv:hep-ph/0608098},
year = {2009}
}