The pion_0 to gamma gamma decay and the chiral anomaly in the quark-composites approach to QCD

TL;DR

This paper calculates the neutral pion decay into two photons using an effective QCD-based approach, confirming the standard decay amplitude and the chiral anomaly within this framework.

Contribution

It introduces a quark composites approach to derive an effective action that reproduces known decay amplitudes and the chiral anomaly in QCD.

Findings

Successfully reproduces the standard pion_0 to gamma gamma decay amplitude.

Verifies the correct reproduction of the chiral anomaly.

Validates the quark composites approach as consistent with established QCD results.

Abstract

We evaluate the pion_0 into two gammas decay amplitude by an effective action derived from QCD in the quark composites approach, getting the standard value. We also verify that our effective action correctly reproduces the chiral anomaly.