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arXiv · hep-ph/0609009

Lightest scalars as chiral partners of the Nambu--Goldstone bosons

L. Y. Xiao·H. Q. Zheng·Z. Y. Zhou
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Abstract

We review the spectrum of lightest scalar resonances recently determined using dispersion techniques. The conceptual difference between the pole mass and the bare mass (or the line--shape mass) is stressed. The nature of the lightest scalars are discussed and we argue, without relying on any model details, that the $σ(500)$, $κ(700)$, $a_0(980)$ and $f_0(980)$ may be understood as chiral partners of the Nambu--Goldstone bosons in the linear realization of chiral symmetry. But there remains some difficulties in understanding the role of $f_0(980)$ in this picture.

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L. Y. Xiao, H. Q. Zheng, Z. Y. Zhou. 2006-09-01. Lightest scalars as chiral partners of the Nambu--Goldstone bosons. https://doi.org/10.1016/j.nuclphysbps.2007.08.111

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