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arXiv · 0705.3260

Scalar resonances: scattering and production amplitudes

D. R. Boito·M. R. Robilotta
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Abstract

Scattering and production amplitudes involving scalar resonances are known, according to Watson's theorem, to share the same phase $δ(s)$. We show that, at low energies, the production amplitude is fully determined by the combination of $δ(s)$ with another phase $ω(s)$, which describes intermediate two-meson propagation and is theoretically unambiguous. Our main result is a simple and almost model independent expression, which generalizes the usual $K$-matrix unitarization procedure and is suited to be used in analyses of production data involving scalar resonances.

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D. R. Boito, M. R. Robilotta. 2007-10-08. Scalar resonances: scattering and production amplitudes. https://doi.org/10.1103/physrevd.76.094011

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