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arXiv · hep-ph/0611007

Is the $σ$ meson dynamically generated?

Zhi-hui Guo·L. Y. Xiao·H. Q. Zheng
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Abstract

We study the problem whether the $σ$ meson is generated `dynamically'. A pedagogical analysis on the toy O(N) linear sigma model is performed and we find that the large $N_c$ limit and the $m_σ\to \infty$ limit does not commute. The sigma meson may not necessarily be described as a dynamically generated resonance. On the contrary, the sigma meson may be more appropriately described by considering it as an explicit degree of freedom in the effective lagrangian.

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Zhi-hui Guo, L. Y. Xiao, H. Q. Zheng. 2006-11-01. Is the $σ$ meson dynamically generated?. https://doi.org/10.1063/1.2714402

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