NJL interaction derived from QCD: vector and axial-vector mesons

TL;DR

This paper derives an effective NJL model from QCD to describe vector and axial-vector mesons, achieving good agreement with experimental data using minimal parameters.

Contribution

It extends previous QCD-based NJL models to accurately predict vector and axial-vector meson properties without additional parameters.

Findings

Model accurately predicts $ ho$- and $a_1$-meson masses.

Strong decay widths are consistent with experimental data.

Only one parameter, the current quark mass, is adjusted.

Abstract

In previous works effective non-local $SU(2)\times SU(2)$ NJL model was derived in the framework of the fundamental QCD. All the parameters of the model are expressed through QCD parameters: current light quark mass $m_0$ and average non-perturbative $\alpha_s$. The results for scalar and pseudo-scalar mesons are in satisfactory agreement to existing data. In the present work the same model without introduction of any additional parameters is applied for a description of masses and strong decay widths of $\rho$- and $a_1$-mesons. The results for both scalar and vector sectors agree with data with only one adjusted parameter $m_0$, with account of average $\alpha_s \simeq 0.415$, which is obtained in a previous work as well.