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arXiv · hep-ph/9906459

Vector mesons in the Extended Chiral Quark Model

A. A. Andrianov·D. Espriu
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Abstract

We extend our previous formulation of low-energy QCD in terms of an effective lagrangian containing operators of dimensionality $d\le 6$ constructed with pseudoscalars and quark fields, describing physics below the scale of chiral symmetry breaking. We include in this paper the vector and axial-vector channels. We follow closely the Extended Chiral Quark Model approach and consistently work in the large-$N_c$ and leading log approximation and take into account the constraints from chiral symmetry and chiral symmetry restoration. The optimal fit of all parameters gives further support to a heavy scalar meson with a mass $\sim 1$ GeV and a value of the axial pion-quark coupling constant $g_A \simeq 0.55$ to 0.66, depending on some assumptions concerning the Weinberg sum rules.

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A. A. Andrianov, D. Espriu. 1999-08-20. Vector mesons in the Extended Chiral Quark Model. https://doi.org/10.1088/1126-6708%2F1999%2F10%2F022

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