Study of the ground and excited states of Lambda and Sigma hyperon   production at COSY
  COSY with a maximum beam momentum of ~3.65 GeV/c allows the production of ground state (Lambda and Sigma) and excited hyperons (Lambda(1405), Sigma(1385) and Lambda(1520)) in elementary NN interactions. The existing data base in this field is rather poor. A systematic study of the hyperon production at COSY will result in an improvement of our understanding concerning topics like hyperon-nucleon interaction, kaon-nucleon interaction, nucleon resonances, strangeness production mechanism and structure of the Lambda(1405). Precise data on Lambda and Sigma production have been produced at the COSY-11 and TOF installation. With the WASA detector at COSY these studies can be continued and extended to channels including photons in the final state. 
D. Grzonka