2 a New Analysis of the Π + Π − and Π 0 Π 0 Data ∗ R . Kamiński , L . Leśniak and K . Rybicki
نویسندگان
چکیده
A joint analysis of the ππ and ππ S-wave amplitudes including results of three experiments has been performed. Using our theoretical model of the ππ production in which not only the pion exchange but also the a1 meson exchange were taken into account we have obtained a unique solution (called ”down-flat”) for the scalar-isoscalar phase shifts. Thus a long-standing problem of ambiguities in the S-wave isoscalar amplitude has been finally resolved and the second (”upflat”) solution was eliminated. PACS 13.60.Le, 13.75Lb, 14.40Cs Analyses of experiments on the ππ production processes are important sources of information about the properties of the scalar mesons. Our knowledge of the basic parameters for the scalar-isoscalar mesons like f0(500), f0(980), f0(1370) or f0(1500) is still very limited. This makes tests of the QCD predictions about a possible existence of the scalar glueballs in the 1 to 2 GeV range to be very difficult. The existence of ambiguities in the ππ S-wave isoscalar amplitude has been a serious problem since more than thirty years. Two experiments on ∗Presented by L. Leśniak at the Meson 2002, Seventh International Workshop on Production, Properties and Interaction of Mesons, Cracow, Poland, May 24-28, 2002
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