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arXiv · 0811.4510

Sigma pole position and errors of a once and twice subtracted dispersive analysis of pi-pi scattering data

R. Kaminski·R. Garcia-Martin·P. Grynkiewicz·J. R. Pelaez
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Abstract

We show how the new precise data on kaon decays together with forward dispersion relations, sum rules and once- and twice-subtracted Roy's equations allow for a precise determination of the sigma meson pole position. We present a comparison and a study of the different sources of uncertainties when using either once- or twice-subtracted Roy's equations to analyze the data. Finally we present a preliminary determination of the sigma pole from the constrained dispersive data analysis.

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R. Kaminski, R. Garcia-Martin, P. Grynkiewicz, J. R. Pelaez. 2009-03-25. Sigma pole position and errors of a once and twice subtracted dispersive analysis of pi-pi scattering data. https://doi.org/10.1016/j.nuclphysbps.2008.12.071

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