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arXiv · hep-ph/0011293

The S-wave Λπphase shift is not large

Ulf-G. Meißner·José Antonio Oller
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Abstract

We study the strong interaction S-wave Λπphase shift in the region of the Ξmass in the framework of a relativistic chiral unitary approach based on coupled channels. All parameters have been previously determined in a fit to strangeness S= -1 S-wave kaon-nucleon data. We find 0^\circ \le δ_0 \le 1.1^\circ in agreement with previous chiral perturbation theory calculations (or extensions thereof). We also discuss why a recent coupled channel K-matrix calculation gives a result for δ_0 that is negative and much bigger in magnitude. We argue why that value should not be trusted.

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Ulf-G. Meißner, José Antonio Oller. 2000-11-23. The S-wave Λπphase shift is not large. https://doi.org/10.1103/physrevd.64.014006

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