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Constituent quark-based linear $σ$ model (L$σ$M) quark and scalar mesons, vector meson dominance

Michael D. Scadron·Miroslav Nagy
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Abstract

After describing the SU(2) linear sigma model (L$σ$M), we dynamically generate it using the B.W. Lee null tadpole sum (characterizing the true vacuum) together with the dimensional regularization lemma. Next we generate the chiral-limiting (CL) nonstrange and strange constituent quark masses ${\hat m}=325.7$ MeV; $m_s=486$ MeV away from the CL. Finally, we study vector meson dominance (VMD) and the pion, kaon charge radii and the loop-order $ρ\toπγ$, $π^0\toγγ$ amplitudes in the quark model. Lastly, we verify this procedure using tree-order VMD graphs.

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Michael D. Scadron, Miroslav Nagy. 2005-07-14. Constituent quark-based linear $σ$ model (L$σ$M) quark and scalar mesons, vector meson dominance. https://arxiv.org/abs/hep-ph/0507168

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