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    Experimental disagreements with Extended Unitarity

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    In production processes, e.g. J/Psi -> omega-pi-pi or pbar-p -> 3pi, the sigma and fo(980) overlap in the same partial wave. The conjecture of Extended Unitarity (EU) states that the pi-pi pair should have the same phase variation as pi-pi elastic scattering. This is an extension of Watson's theorem beyond its original derivation, which stated only that the s-dependence of a single resonance should be universal. The prediction of EU is that the deep dip observed in pi-pi elastic scattering close to 1 GeV should also appear in production data. Four sets of data disagree with this prediction. All require different relative magnitudes of sigma and fo(980). That being so, a fresh conjecture is to rewrite the 2-body unitarity relation for production in terms of observed magnitudes. This leads to a prediction different to EU. Central production data from the AFS experiment fit naturally to this hypothesis.Comment: 24 pages, 12 figures. To be published in Euro. Phys. J

    Sigma, Kappa and fo(980) in E791 and BES II data

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    Both sigma and kappa are well established from E791 data on D->3pi and D->K-pi-pi$ and BES II data on J/Psi->omega-pi-pi and KKpipi. Fits to these data are accurately consistent with pi-pi and Kpi elastic scattering when one allows for the Adler zero which arises from Chiral Symmetry Breaking. The phase variation with mass is also consistent between elastic scattering and production data.Comment: 15 pages, 8 figures. A shortened version of hep-ex.0510014, conforming to page restrictions for Hadron05 Proceeding
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