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arXiv · 0905.2139

Once and twice subtracted dispersion relations in the analysis of pi pi amplitudes

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

Once and twice subtracted crossing symmetric dispersion relations applied to $ππ\to ππ$ scattering data are analyzed and compared. Both sets of dispersion relations can be used to test the $ππ$ amplitudes in low partial waves up to about 1 GeV. We show how once subtracted dispersion relations can provide stronger constraints for $ππ$ amplitudes than twice subtracted ones in the 400 to 1100 MeV range, given the same experimental input.

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R. Kaminski, R. Garcia-Martin, J. R. Pelaez, F. J. Yndurain. 2009-05-13. Once and twice subtracted dispersion relations in the analysis of pi pi amplitudes. https://arxiv.org/abs/0905.2139

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