ar X iv : h ep - p h / 05 10 21 6 v 1 1 7 O ct 2 00 5 Chiral - dispersive calculations of ππ scattering confront experiment ∗
نویسنده
چکیده
In a series of papers we have applied several sum rules and forward dispersion relations, to ππ scattering. We have found that some widely used data sets fail to satisfy these constraints, and we have provided an amplitude that describes data consistently with the dispersive tests. Furthermore, we noted that the input and precision claimed in a Roy equation analysis by Colangelo, Gasser and Leutwyler (CGL), lead to several mismatches with some sum rules. Subsequently, Caprini, Colangelo, Gasser and Leutwyler claimed that our Regge parametrization was incorrect. We collect here the answers to their various claims, and try to clarify the points of agreement and disagreement, showing experimental evidence that substantiates our results, and that, in addition, their representation fails to satisfy all three forward dispersion relations up to √ s ≤ 800 MeV by several standard deviations.
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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