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QCD sum rule approach for the light scalar mesons as four-quark states

Thiago V. Brito·Fernando S. Navarra·Marina Nielsen·Mirian E. Bracco
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Abstract

We study the two point-function for the scalar mesons $σ, κ, f_0(980)$ and $a_0(980)$ as diquak-antidiquark states. We also study the decays of these mesons into $ππ$, $Kπ$ and $K\bar{K}$. We found that the couplings are consistent with existing experimental data, pointing in favor of the four-quark structure for the light scalar mesons.

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Thiago V. Brito, Fernando S. Navarra, Marina Nielsen, Mirian E. Bracco. 2004-11-17. QCD sum rule approach for the light scalar mesons as four-quark states. https://doi.org/10.1016/j.physletb.2005.01.008

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