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Upper limit for the cross section of the overlapping scalar resonances f0(980) and a0(980) produced in proton-proton collisions in the range of the reaction threshold

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 نشر من قبل Moskal
 تاريخ النشر 2003
  مجال البحث
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Utilizing a missing mass technique we investigate the pp --> ppX reaction scanning beam energies in the range permitting to create a mass close to that of the f0(980) and a0(980) scalar resonances, but still below the K^+K^- threshold where they decay dominantly into pi pi and pi eta mesons, respectively. Prior to the data analysis we introduce a notion of the close to threshold total cross section for broad resonances. We estimated for the overlapping mesons a0 and f0 the total cross section to be smaller than 430 nb at excess energy of Q = 5 MeV. The experiment have been performed at the Cooler Synchrotron COSY using the COSY-11 facility.



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