Analyzing power Ay for ω meson production in proton-proton collisions

We report on a determination of the analyzing power Ay in the p→p→ppω reaction studied with the TOF spectrometer located at the COSY-accelerator (Forschungszentrum Jülich, Germany). This spectrometer is very well suited for polarization measurements due to its rotational symmetry and full coverage of the azimuthal angle. For a beam momentum of p=3065MeV/c corresponding to an excess energy of ϵ=129MeVAy is found to be compatible with zero.