2000/09/04 by Yu. S. Surovtsev, D. Krupa, M. Nagy
Physics and Astronomy · #hep-ph
published as Acta Phys.Polon. B31 (2000) 2697-2701 · 15 pages, 5 figures, LaTex; Talk given at the Sixth International Workshop on Production, Properties and Interaction oh Mesons "MESON'2000" (Cracow, Poland, 19-23 May 2000)
arxiv created 2000/09/04 · arxiv updated 2009/11/30
In the model-independent approach consisting in the immediate application to the analysis of experimental data of such general principles as analyticity and unitarity, a confirmation of the σ-meson at ∼ 665 MeV and an indication for the glueball nature of the f0(1500) state are obtained on the basis of a simultaneous description of the isoscalar s-wave channel of the ππ scattering (from the threshold up to 1.9 GeV) and of the ππ→ KK process (from the threshold to ∼ 1.4 GeV where the 2-channel unitarity is valid). A parameterless description of the ππ background is first given by allowance for the left-hand branch-point in the proper uniformizing variable. It is shown that the large ππ-background, usually obtained, combines, in reality, the influence of the left-hand branch-point and the contribution of a very wide resonance at ∼ 665 MeV. The coupling constants of the observed states with the ππ and KK systems and lengths of the ππ and KK scattering are obtained.