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arXiv · hep-ph/9807326

Another look at $ππ$ scattering in the scalar channel

Keiji Igi·Ken-ichi Hikasa
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Abstract

We set up a general framework to describe $ππ$ scattering below 1 GeV based on chiral low-energy expansion with possible spin-0 and 1 resonances. Partial wave amplitudes are obtained with the $N/D$ method, which satisfy unitarity, analyticity and approximate crossing symmetry. Comparison with the phase shift data in the J=0 channel favors a scalar resonance near the $ρ$ mass.

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Keiji Igi, Ken-ichi Hikasa. 1998-07-10. Another look at $ππ$ scattering in the scalar channel. https://doi.org/10.1103/physrevd.59.034005

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