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arXiv · hep-ph/0012235

Scalar Mesons in QCD

Stephan Narison
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Abstract

We review the analysis of the quark and gluon substructures of the scalar mesons from QCD spectral sum rules and some low-energy theorems applied to the scalar QCD anomaly current. The present data favour equal components of \bar uu+ \bar dd and of gg in the wave functions of the low-mass (below 1 GeV) scalar mesons, which make the wide σand the narrow f_0(980) as η'-like particles, which can have strong couplings to meson pairs through OZI violations. 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. 2000-12-18. Scalar Mesons in QCD. https://doi.org/10.1016/s0920-5632(01)01137-9

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