ar X iv : h ep - p h / 03 10 08 2 v 1 7 O ct 2 00 3 Roy ’ s equations and the ππ experimental data
نویسنده
چکیده
Roy’s equations are used to check if the scalar-isoscalar ππ scattering amplitudes fitted to experimental data fulfill crossing symmetry conditions. It is shown that the amplitudes describing the “down-flat” phase shift solution satisfy crossing symmetry below 1 GeV while the amplitudes fitted to the “up-flat” data do not. In this way the long standing ”up-down” ambiguity in the phenomenological determination of the scalar-isoscalar ππ amplitudes has been resolved confirming the independent result of the recent joint analysis of the ππ and ππ data.
منابع مشابه
ar X iv : h ep - p h / 05 10 21 8 v 1 1 7 O ct 2 00 5 ππ scattering amplitudes constrained
The scalar-isoscalar, scalar-isotensor and vector-isovector ππ amplitudes have been fitted simultaneously to experimental data and to to Roy’s equations. Resulting ππ phase shifts up to 1600 MeV and near threshold observables have been analyzed. Only the amplitudes fitted to the ”down-flat” set of phase shifts in scalarisoscalar wave fulfill crossing symmetry conditions and can be regarded as p...
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