Energy dependence of the Lambda/Sigma0 production cross section ratio in   p-p interactions
  Measurements of the near threshold Lambda and Sigma0 production via the pp-->pK+Lambda/Sigma0 reaction at COSY--11 have shown that the Lambda/Sigma0 cross section ratio exceeds the value at high excess energies Q>=300 MeV by an order of magnitude. For a better understanding additional data have been taken between 13 MeV and 60 MeV excess energy. Within the first 20 MeV excess energy a strong decrease of the cross section ratio is observed, with a less steep decrease in the higher excess energy range. A description of the data with a parametrisation including p-Y final state interactions suggests a much smaller p-Sigma0 FSI compared to the p-Lambda system. 
P. Kowina, H.-H. Adam, A. Budzanowski, R. Czyzykiewicz, D. Grzonka, M.   Janusz, L. Jarczyk, B. Kamys, A. Khoukaz, K. Kilian...