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تسجيل مستخدم جديدDouble-polarization observable G in neutral-pion photoproduction off the proton
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This paper reports on a measurement of the double-polarization observable G in $pi^0$ photoproduction off the proton using the CBELSA/TAPS experiment at the ELSA accelerator in Bonn. The observable G is determined from reactions of linearly-polarized photons with longitudinally-polarized protons. The polarized photons are produced by bremsstrahlung off a properly oriented diamond radiator. A frozen spin butanol target provides the polarized protons. The data cover the photon energy range from 617 to 1325 MeV and a wide angular range. The experimental results for G are compared to predictions by the Bonn-Gatchina (BnGa), Julich-Bonn (JuBo), MAID and SAID partial wave analyses. Implications of the new data for the pion photoproduction multipoles are discussed.
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