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تسجيل مستخدم جديدI=0, C=-1 mesons from 1940 to 2410 MeV
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New Crystal Barrel data are reported for pbar-p -> omega-eta and pbar-p -> omega-pizero-pizero with omega decaying to piplus-piminus-pizero. The omega-eta data confirm angular distributions obtained earlier from data where omega -> pizero-gamma. The new omega-eta data provide accurate measurements of vector and tensor polarisations of the omega and lead to considerable improvements in masses and widths of s-channel resonances. A new J^PC = 3^+- I = 0 resonance is observed with mass M = 2025+-20 MeV and width Gamma = 145+-30 MeV. Polarisation is close to zero everywhere and tensor polarisations are large, as is the case also for pbar-p -> omega-pizero.
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New Crystal Barrel data are reported for pbar-p -> omega-pizero and pbar-p -> omega eta-pizero with omega decaying to piplus-piminus-pizero. The shapes of angular distributions agree well with those for data where omega -> pizero-gamma; this is a val
uable cross-check on systematic errors. The new data provide good measurements of vector and tensor polarisations P_y, T20, T21 and T22 of the omega. These lead to significant improvements in parameters of several resonances reported earlier. New values of masses and widths (in Mev) are: J^PC = 5^-- (2300+-45, 260+-75), J^PC = 3^-- (2260+-20, 160+-25), J^PC = 1^+- (2240+-35, 320+-85), and J^PC = 1^-- (2110+-35, 230+-50). A remarkable feature of the data is that vector polarisation P_y is close to zero everywhere. It follows that all interfering amplitudes have relative phases close to 0 or 180 deg. Tensor polarisations are large.
Data on pbar-p -> 3eta for beam momenta 600--1940 MeV/c are presented. The strongest channel is f_0(1500)-eta from the initial pbar-p state 1S0. Together with eta-pizero-pizero data, the 3eta data determine the branching ratio BR[f_0(1500) -> eta-eta
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A partial wave analysis of antiproton-proton annihilation data in flight at 900 $MeV/c$ into $pi^0 pi^0 eta$ , $pi^0 eta eta$ and $K^+ K^- pi^0$ is presented. The data were taken at LEAR by the Crystal Barrel experiment in 1996. The three channels ha
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