Low-energy photon-photon fusion into three pions in Generalized Chiral Perturbation Theory

TL;DR

This paper calculates low-energy photon-photon fusion into three pions using Generalized Chiral Perturbation Theory, exploring its sensitivity to chiral symmetry breaking and estimating event rates for specific experimental facilities.

Contribution

It provides the first detailed amplitude calculations for these processes up to order p^6 within the generalized framework, highlighting their experimental relevance.

Findings

Amplitudes computed up to order p^6 in GChPT.

Estimated event rates for Daphne $$-Factory and future $ au$-Charm Factory.

Potential sensitivity to chiral symmetry breaking mechanisms.

Abstract

The processes $\gamma\gamma\to\pi^0\pi^0\pi^0$ and $\gamma\gamma\to \pi^+ \pi^- \pi^0$ are considered in Generalized Chiral Perturbation theory, in view of their potential sensitivity to the mechanism of spontaneous breaking of chiral symmetry and to various counterterms. The amplitudes are computed up to order ${\cal O}(p^6)$. The event production rates are estimated for the Daphne $\phi$-Factory and for a future $\tau$-Charm Factory.