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arXiv · 1307.2031

Composite and elementary nature of a resonance in the sigma model

Hideko Nagahiro·Atsushi Hosaka
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Abstract

We analyze the mixing nature of the low-lying scalar resonance consisting of the pipi composite and the elementary particle within the sigma model. A method to disentangle the mixing is formulated in the scattering theory with the concept of the two-level problem. We investigate the composite and elementary components of the sigma meson by changing a mixing parameter. We also study the dependence of the results on model parameters such as the cut-off value and the mass of the elementary sigma meson.

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Hideko Nagahiro, Atsushi Hosaka. 2013-07-08. Composite and elementary nature of a resonance in the sigma model. https://doi.org/10.1103/physrevc.88.055203

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