Measurement of the Asymmetry of Photoproduction of π^– Mesons on Linearly Polarized Deuterons by Linearly Polarized Photons

The first results of a double polarization experiment to extract the asymmetry of the reaction of photoproduction of a π^- meson by a linearly polarized photon on a tensor-polarized deuteron in the energy range of the virtual photon (300–700 MeV) are presented. The measurements were performed on an internal tensor-polarized deuterium target in the VEPP-3 electron-positron storage ring for the electron beam energy equal to 2 GeV. The experiment employed the method of recording two protons and the scattered electron in coincidence. The obtained measurement results are compared with the theoretical predictions obtained in the momentum approximation with allowance for πN and NN rescattering in the final state.