A theoretical determination of the eta-eta' mixing

TL;DR

This paper theoretically determines the eta-eta' mixing angle using large N_c limit in chiral perturbation theory, achieving good agreement with experimental data after considering higher order corrections.

Contribution

It provides a theoretical calculation of the eta-eta' mixing angle within the large N_c limit framework, including higher order corrections.

Findings

Optimal mixing angle of about -27 degrees at leading order

Higher order corrections of about 20% improve data agreement

Framework aligns theoretical predictions with experimental observations

Abstract

The systematic large N_c limit within chiral perturbation provides an optimal eta-eta' mixing angle of about -27 degrees at leading order in p^2. In this frame, agreement with the data can be reached with higher order corrections of about 20%.