Speaker
            
    Damir Bosnar
        
            (Faculty of Science)
        
    Description
An overview of the previous measurements of the polarization of photons in positronium annihilations, with special emphasis on ortho-positronium annihilations, will be given. Possibilities for the measurements of the polarization of all three photons in ortho-positronium annihilations with single-layer Compton scattering detector systems developed at the Department of Physics in Zagreb as well as the first measurements will be presented.