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On the Quark and Gluon Substructure of the Sigma and other Scalar Mesons

Stephan Narison
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Abstract

Within the increasing experimental evidence of the existence of the I=0 scalar low mass and wide σmeson, we review the {\it first} analysis of its quark and gluon substructure from QCD spectral sum rules and some low-energy theorems. The present data favour equal components of \bar uu+ \bar dd and of gg in its wave function, which make the wide sigma and the narrow f_0(980) as η'-like particles. A coherent picture of the other I=0 scalar mesons spectra within this mixing scheme is shortly discussed. We also expect the a_0(980) to be the lowest isovector \bar ud state, and the K^*_0(1430) its \bar ds partner.

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Stephan Narison. 2000-09-10. On the Quark and Gluon Substructure of the Sigma and other Scalar Mesons. https://arxiv.org/abs/hep-ph/0009108

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