Measuring the particle polarization in a storage ring by the method of synchrotron radiation scattering on intersecting beam

A new method of measurement of polarization electron-positron colliding beams is described. The method based on the measurement of angular asymmetry of circularly polarized photon scattering on a beam of polarized electrons (positrons). Colliding beam synchrotron radiation is used as a source of circularly polarized photons. To record scattered photons and to measure their energies, NaI(Tl) counters are used. The ''up-down'' asymmetry is measured by two scintillation counters, having 1 mm gap in the vertical direction. A lead converter 7 mm thick was located in front of the counters, which also served as a shielding from direct synchrotron radiation. The method of polarization measurement was used in the experiment on precise measurement of γ-meson mass at the VEPP-4 with the MD-1 detector. The accuracy of the mass measurement in the experiment was improved by a factor of 15 as compared with table value