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A New Analysis of the pi+pi- and pi0pi0 Data

R. Kaminski·L. Lesniak·K. Rybicki
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Abstract

A joint analysis of the pi+pi- and pi0pi0 S-wave amplitudes including results of three experiments has been performed. Using our theoretical model of the pion-pion production in which not only the pion exchange but also the a1(1260) 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 ("up-flat") solution was eliminated.

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R. Kaminski, L. Lesniak, K. Rybicki. 2002-07-04. A New Analysis of the pi+pi- and pi0pi0 Data. https://doi.org/10.1142/9789812791351_0035

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