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What does `rho-exchange' in piN scattering mean?

O. Krehl·C. Hanhart·S. Krewald·J. Speth
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Abstract

We present an alternative method for calculating amplitudes for correlated pi pi exchange in the ``sigma'' and rho channel in piN scattering. Starting from a fixed mass meson exchange potential, we introduce the width of the exchanged particles by integrating over a mass spectral function. The spectral functions are constructed from the pseudoempirical N\bar{N} -> pi pi data. Using this approach we develop a prescription for resolving ambiguities of the correlated pi pi exchange in the rho channel that occur when different dispersion theoretical formulations of rho exchange are used to construct piN potentials.

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O. Krehl, C. Hanhart, S. Krewald, J. Speth. 1999-06-29. What does `rho-exchange' in piN scattering mean?. https://doi.org/10.1103/physrevc.60.055206

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