η production by proton-nucleon and proton-nucleus interactions from 800 MeV to 1.5 GeV

In the last few years both theoretical and experimental efforts have been made to study the production of η particles on nucleons and nuclei; in particular great interest has been shown in measuring these processes near threshold, where it seems to be dominated by the N (1535) resonance production. Moreover the measurement of the η production in nucleus-nucleus collisions has been used as a tool for studying the Equation of state of compressed nuclear matter which is necessary in order to understand dilepton production in nuclei. Focusing our attention on the experimental aspects of this research, recently we have undertaken a program aiming to study the production of the η meson on nucleons and nuclei by protons at Saturne. (author)