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arXiv · hep-ph/0006083

The light sigma meson

V. V. Anisovich·V. A. Nikonov
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Abstract

In the framework of the dispersion relation N/D-approach, we restore the low-energy pi-pi (IJ^{PC}=00^{++})-wave amplitude sewing it with the previously obtained K-matrix solution for the region 450-1900 MeV. The restored N/D-amplitude has a pole on the second sheet of the complex-s plane near the pi-pi threshold, that is the light sigma meson.

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V. V. Anisovich, V. A. Nikonov. 2000-06-09. The light sigma meson. https://doi.org/10.1007/s100500070093

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