Partial widths for the decays eta(1295) -> gamma gamma and eta(1440) -> gamma gamma

TL;DR

This paper investigates the gamma gamma decay widths of eta(1295) and eta(1440) mesons, suggesting their dominant nar n composition and small sar s contribution within a quark model framework.

Contribution

It provides a theoretical analysis of the partial widths of eta(1295) and eta(1440) decays assuming they are first radial excitation nonet mesons, highlighting their quark content.

Findings

Partial widths are around 0.1 keV.

Decay widths are mainly due to nar n components.

sar s contribution is minimal.

Abstract

We discuss gamma gamma partial widths of pseudoscalar/isoscalar mesons eta(M) in the mass region M = 1000-1500 MeV. The transition amplitudes eta(1295) -> gamma gamma and eta(1440) -> gamma gamma are studied within an assumption that the decaying mesons are the members of the first radial excitation nonet 2^1S_0 q\bar q. The calculations show that partial widths being of the order of 0.1 keV are dominantly due to the n\bar n meson component while the contribution of the s\bar s component is small.