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arXiv · 0804.2632

Precise analysis of pion-pion scattering data from Roy equations and forward dispersion relations

J. R. Pelaez·R. Garcia-Martin·R. Kaminski·F. J. Yndurain
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Abstract

We review our recent analysis of pion-pion scattering data in terms of Roy equations and Forward Dispersion Relations, and present some preliminary results in terms of a new set of once-subtracted coupled equations for partial waves. The first analysis consists of independent fits to the different pion-pion channels that satisfies rather well the dispersive representation. In the second analysis we constrain the fit with the dispersion relations. The latter provides a very precise and model independent description of data using just analyticity, causality and crossing.

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J. R. Pelaez, R. Garcia-Martin, R. Kaminski, F. J. Yndurain. 2008-04-16. Precise analysis of pion-pion scattering data from Roy equations and forward dispersion relations. https://doi.org/10.1063/1.2973509

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