To the problem of 1/Nc approximation in the Nambu-Jona-Lasinio model

TL;DR

This paper investigates the gap equation for quark mass in the U(2)*U(2) Nambu-Jona-Lasinio model within the 1/Nc approximation, emphasizing the importance of scalar isovector mesons and Ward identities for accurate descriptions.

Contribution

It highlights the significance of scalar isovector mesons and Ward identities in improving the 1/Nc approximation of the NJL model for quark masses.

Findings

Scalar isovector mesons are crucial for correct quark mass description.

Ward identities are important in calculating 1/Nc corrections.

The role of mesons in the NJL model is clarified.

Abstract

In this article, the gap equation for the constituent quark mass in the U(2)*U(2) Nambu-Jona-Lasinio model for the 1/Nc approximation is investigated. It is shown that taking into account scalar isovector mesons plays an important role for the correct description of quark masses in this approximation. The role of the Ward identity in calculations of 1/Nc corrections to the meson vertex functions is shortly discussed.