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تسجيل مستخدم جديدFirst measurement of the circular beam asymmetry in the gamma p --> pi0 eta p reaction
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The circular photon asymmetry for pi0 eta photoproduction on the proton was measured for the first time at the tagged photon facility of the MAMI C accelerator using the Crystal Ball/TAPS photon spectrometer. The experimental results are interpreted within a phenomenological isobar model that confirms the dominant role of the Delta(1700)D33 resonance. The measured asymmetry allows us to identify small contributions from positive-parity resonances via interference terms with the dominant D33 amplitude.
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The gamma p --> pi0 pi0 p reaction has been measured from threshold to 1.4 GeV using the Crystal Ball and TAPS photon spectrometers together with the photon tagging facility at the Mainz Microtron. The experimental results include total and different
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The first data on target and beam-target asymmetries for the $gamma ptopi^0eta p$ reaction at photon energies from 1050 up to 1450 MeV are presented. The measurements were performed using the Crystal Ball and TAPS detector setup at the Glasgow tagged
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A measurement of the pp --> p p eta reaction at the excess energy of Q = 15.5 +- 0.4 MeV has been carried out at the internal beam facility COSY-11 with an integrated luminosity of 811 nb^-1 The number of ~24000 identified events permits a precise de
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